Tagged: temblor Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 4:47 pm on June 30, 2022 Permalink | Reply
    Tags: "A landslide and a tsunami and then a flood:: the massive hazard cascade that shook the world", A signal comparable to a magnitude-5.0 earthquake emanated from deep within the southern Coast Mountains of British Columbia., , , British Columbia’s mountainous terrain is no stranger to landslides or floods and tsunamis., , , , New research reveals the intensity of British Columbia’s 2020 hazard cascade as members of the Homalco First Nation continue to pick up the pieces., , Recovery could take decades., temblor, The fifth largest landslide on record in British Columbia., The sheer scale of the cascade can be hard to comprehend even when viewing the valley from a helicopter.,   

    From temblor : “A landslide and a tsunami and then a flood:: the massive hazard cascade that shook the world” 

    1

    From temblor

    June 30, 2022
    Lauren A. Koenig, Ph.D.

    New research reveals the intensity of British Columbia’s 2020 hazard cascade as members of the Homalco First Nation continue to pick up the pieces.

    In late November, 2020 a geological mystery appeared on seismographs around the world. A signal comparable to a magnitude-5.0 earthquake emanated from deep within the southern Coast Mountains of British Columbia (B.C.), Canada.

    The cause of this ground-shaking event remained unknown for two weeks, until forestry workers passing through traditional territory of the Homalco First Nation happened upon its aftermath in the Elliot Creek watershed. The glacier-carved valley, narrowly framed by mile-high rocky walls, was decimated by a massive hazard cascade — a chain reaction of geological events — involving a landslide, tsunami, outburst flood and sediment plume. What was once a verdant environment for the region’s famed salmon is now an ashen alley that fans out into a sea of debris.

    The sheer scale of the cascade can be hard to comprehend even when viewing the valley from a helicopter, said Marten Geertsema, a research geomorphologist with the B.C. Ministry of Forests and the lead author of a new study that describes the events [Geophysical Research Letters].


    British Columbia 2020 hazard cascade aftermath.

    “It’s staggering when you just stand there,” said Geertsema. “It’s kind of hard to wrap your head around how powerful that all was.”

    Homalco First Nation and researchers from the B.C.-based Hakai Institute are assessing the long-term ecological impacts on the region, especially for fisheries. Ongoing unstable conditions in the valley suggest that recovery could take decades. Moreover, Elliot Creek has erratically changed course numerous times in the past year, which can make restoration plans irrelevant essentially overnight.

    “If we get a massive rain event like last year, the whole river could change again and it’s not money well spent,” said Erik Blaney, an environmental technical of the Tla’amin Nation who was contracted by the Homalco Nation to lead assessment and recovery efforts. “You’re playing with mother nature.”

    A cascade of unfortunate events

    The hazard cascade began with the fifth largest landslide on record in British Columbia, involving, according to study co-author Göran Ekström, the equivalent of the combined mass of Canada’s 25 million cars. Ekström is a seismologist at Columbia University. Nearly half of the debris crashed onto the toe of West Grenville glacier, near the base of the valley. The rest ran up the opposite wall of the valley before gravity carried it down once again. Traveling at more than 100 miles per hour (170 kilometers per hour), the landslide plunged into an alpine lake left behind by the glacier during its retreat over the last century.

    Like the splash after a jump off a high-dive, the landslide’s impact was fast and violent: the rockfall catapulted enough water out of the lake to reduce its area by nearly 20%, creating islands in its newly shallow depths. In just over a minute, a tsunami wave towering more than 330 feet (100 meters) high sped across the lake before cresting the opposite shore, creating what is known as a glacial lake outburst flood.

    2
    The view down valley showing the eroded creek bed and lack of vegetation. Credit: Briar Stewart/CBC.

    The water was then forcefully channeled down the confines of the valley like a marble in a Rube Goldberg machine. Though it generally takes millennia for water to steadily erode deep ravines, the flood gouged out a groove 160 feet (50 meters) deep in the stream bed within minutes.

    As the creek bank gave way and trees were mowed down, the flood became a thick soup of debris that left an enormous fan of sand, mud and wood extending from the mouth of the valley. It contaminated local fresh and marine waterways, creating a sediment plume — suspended organic materials — that destroyed water quality.

    “You need certain elements in place to create these massive domino effects,” said Geerstema. “This goes to show us the damaging footprint of these events when you have water in the right place.”

    Looking with LiDAR

    The landslide’s remote location meant that fortunately no one was around when the hazard cascade took place. To map out what happened, Geertsema, who regularly scours satellite imagery for evidence of landslides in high-mountain areas, worked with members of Canada’s First Nations, the Hakai Institute and other institutions around the world to simulate the events using numerical modeling and LiDAR — a survey method that pulses lasers from an airplane to create 3D representations of the surface.

    Geertsema, who compared post-landslide images with those taken only one year prior, said the team was very lucky to have such detailed imagery. “We wouldn’t have been able to produce these models without that input data,” he said.

    3
    The view of the lake looking towards West Grenville glacier and the sheer vertical slide face. Credit: Brian Menounos.

    Fewer glaciers, more hazards

    British Columbia’s mountainous terrain is no stranger to landslides or floods and tsunamis. Climate change, however, has exacerbated the impacts and frequency of these hazards — especially as warming temperatures cause ground-stabilizing permafrost and glaciers to melt away.

    As glaciers retreat, weak bedrock loses the support that prevents its collapse, said Tom Millard, a research geomorphologist with the B.C. Ministry of Forests and co-author of the study. The meltwater lakes left in their wake, such as at Elliot Creek, also tend to get larger, which ratchets up the hazard of a potential tsunami or outburst flood.

    Living with the consequences

    The chain reaction of geological events created a cascade of ecological effects that will linger for decades. The flood destroyed most of the salmon population, as well as the spawning habitat that they return to each year. The fish are unable to survive current turbidity levels, which remain more than 25 times higher than normal (especially after a rainstorm), said Blaney.

    More than food, salmon are an important part of the Homalco First Nation’s culture and livelihood. Grizzly bears’ annual feasting on salmon draws in tourism that helps the community thrive. But this past year, low salmon numbers meant the bears went hungry.

    As recovery effort coordinator, Blaney has ideas for sustainable ways to help the ecosystem return to some semblance of normal. One solution is to prune crab apple trees as another source of food for the bears.

    “It’s something that our people did before,” said Blaney.

    Blaney is also considering installing a platform that would provide a safer way for researchers to monitor the salmon population, diverting the creek through a more stable area with remaining trees, and planting native vegetation to control for erosion.

    Finding funding for these projects, however, is only one obstacle that is part of an even greater challenge: living with the increasingly stark effects of climate change. Severe wildfires in summer 2021 burned across B.C., and the Coast Mountains are experiencing some of the highest rates of glacier loss on earth, meaning hazard cascades like the one at Elliot Creek could become more frequent.

    “I don’t think the average person living in a city can really understand or see the changes that we’re seeing and the devastation that they’re having on salmon and other important pieces of our survival and our culture,” said Blaney. “We’re seeing change, and it’s happening fast and it’s beyond any scope we could have imagined.”

    Further Reading

    For the full multimedia feature by the Hakai Institute — which includes video, interactive maps, and more — click here.

    Geertsema, M., Menounos, B., Bullard, G., Carrivick, J. L., Clague, J. J., Dai, C., … & Sharp, M. A. (2022). The 28 November 2020 landslide, tsunami, and outburst flood–a hazard cascade associated with rapid deglaciation at Elliot Creek, British Columbia, Canada. Geophysical research letters, 49(6), e2021GL096716.

    Menounos, B., Hugonnet, R., Shean, D., Gardner, A., Howat, I., Berthier, E., … & Dehecq, A. (2019). Heterogeneous changes in western North American glaciers linked to decadal variability in zonal wind strength. Geophysical Research Letters, 46(1), 200-209.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    _____________________________________________________________________________________

    Earthquake Alert

    1

    Earthquake Alert

    Earthquake Network projectEarthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    3
    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

    QuakeAlertUSA

    1

    About Early Warning Labs, LLC

    Early Warning Labs, LLC (EWL) is an Earthquake Early Warning technology developer and integrator located in Santa Monica, CA. EWL is partnered with industry leading GIS provider ESRI, Inc. and is collaborating with the US Government and university partners.

    EWL is investing millions of dollars over the next 36 months to complete the final integration and delivery of Earthquake Early Warning to individual consumers, government entities, and commercial users.

    EWL’s mission is to improve, expand, and lower the costs of the existing earthquake early warning systems.

    EWL is developing a robust cloud server environment to handle low-cost mass distribution of these warnings. In addition, Early Warning Labs is researching and developing automated response standards and systems that allow public and private users to take pre-defined automated actions to protect lives and assets.

    EWL has an existing beta R&D test system installed at one of the largest studios in Southern California. The goal of this system is to stress test EWL’s hardware, software, and alert signals while improving latency and reliability.

    Earthquake Early Warning Introduction

    The United States Geological Survey (USGS), in collaboration with state agencies, university partners, and private industry, is developing an earthquake early warning system (EEW) for the West Coast of the United States called ShakeAlert. The USGS Earthquake Hazards Program aims to mitigate earthquake losses in the United States. Citizens, first responders, and engineers rely on the USGS for accurate and timely information about where earthquakes occur, the ground shaking intensity in different locations, and the likelihood is of future significant ground shaking.

    The ShakeAlert Earthquake Early Warning System recently entered its first phase of operations. The USGS working in partnership with the California Governor’s Office of Emergency Services (Cal OES) is now allowing for the testing of public alerting via apps, Wireless Emergency Alerts, and by other means throughout California.

    ShakeAlert partners in Oregon and Washington are working with the USGS to test public alerting in those states sometime in 2020.

    ShakeAlert has demonstrated the feasibility of earthquake early warning, from event detection to producing USGS issued ShakeAlerts ® and will continue to undergo testing and will improve over time. In particular, robust and reliable alert delivery pathways for automated actions are currently being developed and implemented by private industry partners for use in California, Oregon, and Washington.

    Earthquake Early Warning Background

    The objective of an earthquake early warning system is to rapidly detect the initiation of an earthquake, estimate the level of ground shaking intensity to be expected, and issue a warning before significant ground shaking starts. A network of seismic sensors detects the first energy to radiate from an earthquake, the P-wave energy, and the location and the magnitude of the earthquake is rapidly determined. Then, the anticipated ground shaking across the region to be affected is estimated. The system can provide warning before the S-wave arrives, which brings the strong shaking that usually causes most of the damage. Warnings will be distributed to local and state public emergency response officials, critical infrastructure, private businesses, and the public. EEW systems have been successfully implemented in Japan, Taiwan, Mexico, and other nations with varying degrees of sophistication and coverage.

    Earthquake early warning can provide enough time to:

    Instruct students and employees to take a protective action such as Drop, Cover, and Hold On
    Initiate mass notification procedures
    Open fire-house doors and notify local first responders
    Slow and stop trains and taxiing planes
    Install measures to prevent/limit additional cars from going on bridges, entering tunnels, and being on freeway overpasses before the shaking starts
    Move people away from dangerous machines or chemicals in work environments
    Shut down gas lines, water treatment plants, or nuclear reactors
    Automatically shut down and isolate industrial systems

    However, earthquake warning notifications must be transmitted without requiring human review and response action must be automated, as the total warning times are short depending on geographic distance and varying soil densities from the epicenter.

     
  • richardmitnick 8:30 pm on June 13, 2022 Permalink | Reply
    Tags: "Megathrust earthquakes impact surrounding seismicity for centuries", , , , , , , temblor   

    From temblor : “Megathrust earthquakes impact surrounding seismicity for centuries” 

    1

    From temblor

    June 13, 2022
    Ross S. Stein, Ph.D.
    Temblor, Inc.

    Shinji Toda, Ph.D.
    International Research Institute of Disaster Science
    Tohoku University (JP)

    Subduction zones spawn the planet’s largest earthquakes, termed ‘megathrusts’ once they reach magnitude-9.

    Cascadia is projected to unleash a 9+ earthquake event at some point in the future.

    Such shocks release one thousand times the energy of a magnitude-7 event, and thus play a dominant role in the global seismic energy release. However, they occur at a rate only one hundredth of a magnitude-7. On average, there are about five megathrust shocks per century (Kagan and Jackson 2013). The largest instrumentally recorded megathrust was the 1960 Valdivia, Chile, magnitude-9.5 event.

    Most seismic hazard assessments attempt to reflect the long term earthquake rates, which are assumed to slowly change as stress builds on faults. But there is abundant evidence that megathrusts and other very large earthquakes abruptly and profoundly alter the hazard to depart, leading to damaging aftershocks and progressive mainshocks.

    In a study published last week in Nature Geoscience, we argue that after a megathrust earthquake, aftershocks on the rupture surface quickly shut down. At the same time, large aftershocks light up the surrounding area, menacing coastal population centers.

    Aftershock core and corona

    Within five years of each megathrust shock that struck since 1960, aftershocks on the high-slip portions of the rupture surface had shut down. This includes the 1960 magnitrude-9.5 Valdivia, 1964 magnitude-9.2 Prince William Sound, 2004 magnitude-9.2 Sumatra and 2011 magnitude-9.0 Tohoku earthquakes. It is probably also the case for the somewhat smaller 2010 magnitude-8.8 Maule, Chile, quake. In these “cores,” seismicity rates dropped well below the rate observed in the decades before the megathrusts. Immediately after each of these events, a surrounding “corona” of seismicity was activated, and continues to be active today — up to 60 years later. Owning to Japan’s unsurpassed seismic monitoring network, the best recorded of these is the 2011 magnitude-9.0 Tohoku shock.

    2
    During the first several years after the Tohoku mainshock, there were abundant aftershocks in the core and surrounding corona (left panel), but five years later, while the corona remained active, the core had all but shut down (middle panel). Whether the corona extends to Tokyo is uncertain, so is indicated by a light dashed contour (right panel).

    Coulomb stress transfer can explain these observations

    These observations can be explained by the transfer of stress during an earthquake — known as Coulomb stress transfer. Earthquakes generally release the built up stress on the fault that slipped, transferring it to surrounding faults. In the Coulomb hypothesis, both an increase in shear stress and unclamping of a fault promote failure, whereas reducing the shear stress or clamping the fault inhibit failure. These stresses cause seismicity, the rate of which evolves through time (Dieterich, 1994; Stein, 1999). Most corona aftershocks occurred because the faults on which they struck were brought immediately closer to Coulomb failure by the mainshock rupture, suggesting that the corona is a product of stress transfer from the rupture to surrounding faults. In contrast, in the core, the Coulomb stress inhibited most aftershocks. Some faults within the core experience a stress increase, causing a sudden rise in seismicity rate. But these sites are rapidly consumed as aftershocks release this stress, resulting in a delayed shutdown.

    3
    In our model of seismicity evolution, immediately after the mainshocks, the aftershock rate is high in the core (blue), but it drops to a level below the pre-mainshock seismicity rate within several years. In contrast, the corona (red) activates immediately, slowly decaying to (but not below) the pre-mainshock rate over 30-60 years.

    Implications for seismic hazard

    Because the corona is as much as ten times larger than the core, there is a net hazard increase after a megathrust that lasts for about half a century, typically spanning the trench to the coast. Most hazard models, including the “seismic gap theory,” instead assume that the hazard drops after a megathrust. Four roughly magnitude-7 earthquakes struck along the Tohoku coast in 2021-2022 — more than a decade after the mainshock — all in corona areas. We regard these as Tohoku aftershocks, rather than run-of-the-mill earthquakes. In support of this interpretation, there were 22 magnitude-6.7 and greater shocks in the decade after the Tohoku mainshock, but only 4-5 in the same area in the decade beforehand — a four-fold rate increase. In addition, at the site of the magnitude-7 shocks, the rate of small (magnitude-3 and larger) shocks is five times higher today than it was before the 2011 shock. So, in our view, the model exhibits a forecast skill that could be used to improve hazard assessments. In addition to Japan, Chile and Indonesia also suffered megathrusts, which strongly alter their seismic hazard today.

    A new way to hunt for prehistoric megathrusts

    If our model is correct and the core shutdown persists for 300 or so years, then we should be able to find sites of pre-instrumental and prehistoric megathrust earthquakes by searching for current holes in subduction zone seismicity. All four of the megathrusts since 1960 are visible today as seismicity holes, as are the still older 1868 magnitude-9.1 Arica (Peru-Chile), 1762 magnitude-8.8 Arakan (Myanmar) and 1700 magnitude-9.0 Cascadia (US-Canada) earthquakes. Candidate prehistoric megathrust ruptures include a 200-mile-long (300-kilometer) hole along the western Makran Trench and 400-mile-long (700-kilometer) hole along the Commander section of the northwest Aleutian arc.

    4
    Four seismicity holes, several of which correspond to megathrusts that struck more than 250 years ago. The lack of Cascadia seismicity (left panel) has been attributed by others to complete healing and locking of the megathrust (Obana et al. 2014), we believe it could instead be in a post-mainshock shutdown. Sites of megathrusts or very large earthquakes in 1765 and 1762 also appear today as holes (middle and right panels).

    This view is opposite to what most researchers have assumed. Holes have been interpreted as aseismic sections of subduction zones, where megathrusts are not possible. But where aseismic slip, known as “creep,” is independently documented from GPS measurements, it is generally accompanied by moderate seismicity, so these are not seismicity holes. In fact, the Juan de Fuca Trench off the Pacific Northwest was assumed to be permanently aseismic until Brian Atwater and Kenji Satake discovered evidence for the 1700 Cascadia tsunami (Atwater et al. 2016).

    What about the San Andreas?

    Whether seismicity holes might also mark the sites of historic and prehistoric magnitude-8 transform fault ruptures is uncertain. Tantalizingly, the sites of the great 1857 magnitude-7.9 southern San Andreas and 1906 magnitude-7.7 northern San Andreas earthquakes are holes today (Scholz 1988). But because these transform (strike-slip) earthquakes are so much smaller than megathrusts, the seismicity data needed to demonstrate this case worldwide is impoverished, and so the answer remains clouded.

    References

    Atwater, B.F., Musumi-Rokkaku, S., Satake, K., Tsuji, Y., Ueda, K. and D.K. Yamaguchi (2016), The orphan tsunami of 1700: Japanese clues to a parent earthquake in North America. University of Washington Press (USGS Prof. Paper 1707).

    Dieterich, J. H. (1994), A constitutive law for the rate of earthquake production and its application to earthquake clustering. J. Geophys. Res. 99, 2601-2618, https://doi.org/10.1029/93JB02581

    Kagan, Y. Y., and D. D. Jackson (2013), Tohoku Earthquake: A Surprise? Bull. Seismol. Soc. Am. 103, 1181–1194. doi: https://doi.org/10.1785/0120120110

    Obana, K., M. Scherwath, Y. Yamamoto, S. Kodaira, K. Wang, G. Spence, M. Riedel, H. Kao (2014), Earthquake activity in northern Cascadia subduction zone off Vancouver Island revealed by ocean‐bottom seismograph observations. Bull. Seismol. Soc. Am. 105, 489–495. doi: https://doi.org/10.1785/0120140095

    Toda, S. and R. S. Stein (2022), Central shutdown and surrounding activation of aftershocks from megathrust earthquake stress transfer, Nature Geoscience, doi: https://www.nature.com/articles/s41561-022-00954-x. Or freely available from ShareIt https://rdcu.be/cPoHx

    Scholz, C.H. (1988), Mechanisms of seismic quiescences. Pure Appl. Geophys. 126, 701-718, https://doi.org/10.1007/BF00879016

    Stein, R. S. (1999), The role of stress transfer in earthquake occurrence, Nature 402, 605-609, https://doi.org/10.1038/45144

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    _____________________________________________________________________________________

    Earthquake Alert

    1

    Earthquake Alert

    Earthquake Network projectEarthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    3
    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

    QuakeAlertUSA

    1

    About Early Warning Labs, LLC

    Early Warning Labs, LLC (EWL) is an Earthquake Early Warning technology developer and integrator located in Santa Monica, CA. EWL is partnered with industry leading GIS provider ESRI, Inc. and is collaborating with the US Government and university partners.

    EWL is investing millions of dollars over the next 36 months to complete the final integration and delivery of Earthquake Early Warning to individual consumers, government entities, and commercial users.

    EWL’s mission is to improve, expand, and lower the costs of the existing earthquake early warning systems.

    EWL is developing a robust cloud server environment to handle low-cost mass distribution of these warnings. In addition, Early Warning Labs is researching and developing automated response standards and systems that allow public and private users to take pre-defined automated actions to protect lives and assets.

    EWL has an existing beta R&D test system installed at one of the largest studios in Southern California. The goal of this system is to stress test EWL’s hardware, software, and alert signals while improving latency and reliability.

    Earthquake Early Warning Introduction

    The United States Geological Survey (USGS), in collaboration with state agencies, university partners, and private industry, is developing an earthquake early warning system (EEW) for the West Coast of the United States called ShakeAlert. The USGS Earthquake Hazards Program aims to mitigate earthquake losses in the United States. Citizens, first responders, and engineers rely on the USGS for accurate and timely information about where earthquakes occur, the ground shaking intensity in different locations, and the likelihood is of future significant ground shaking.

    The ShakeAlert Earthquake Early Warning System recently entered its first phase of operations. The USGS working in partnership with the California Governor’s Office of Emergency Services (Cal OES) is now allowing for the testing of public alerting via apps, Wireless Emergency Alerts, and by other means throughout California.

    ShakeAlert partners in Oregon and Washington are working with the USGS to test public alerting in those states sometime in 2020.

    ShakeAlert has demonstrated the feasibility of earthquake early warning, from event detection to producing USGS issued ShakeAlerts ® and will continue to undergo testing and will improve over time. In particular, robust and reliable alert delivery pathways for automated actions are currently being developed and implemented by private industry partners for use in California, Oregon, and Washington.

    Earthquake Early Warning Background

    The objective of an earthquake early warning system is to rapidly detect the initiation of an earthquake, estimate the level of ground shaking intensity to be expected, and issue a warning before significant ground shaking starts. A network of seismic sensors detects the first energy to radiate from an earthquake, the P-wave energy, and the location and the magnitude of the earthquake is rapidly determined. Then, the anticipated ground shaking across the region to be affected is estimated. The system can provide warning before the S-wave arrives, which brings the strong shaking that usually causes most of the damage. Warnings will be distributed to local and state public emergency response officials, critical infrastructure, private businesses, and the public. EEW systems have been successfully implemented in Japan, Taiwan, Mexico, and other nations with varying degrees of sophistication and coverage.

    Earthquake early warning can provide enough time to:

    Instruct students and employees to take a protective action such as Drop, Cover, and Hold On
    Initiate mass notification procedures
    Open fire-house doors and notify local first responders
    Slow and stop trains and taxiing planes
    Install measures to prevent/limit additional cars from going on bridges, entering tunnels, and being on freeway overpasses before the shaking starts
    Move people away from dangerous machines or chemicals in work environments
    Shut down gas lines, water treatment plants, or nuclear reactors
    Automatically shut down and isolate industrial systems

    However, earthquake warning notifications must be transmitted without requiring human review and response action must be automated, as the total warning times are short depending on geographic distance and varying soil densities from the epicenter.

     
  • richardmitnick 10:18 am on March 21, 2022 Permalink | Reply
    Tags: " ‘Triplet’ earthquakes strike near Tohoku in Japan but a rupture gap remains", , , , , temblor   

    From temblor: ” ‘Triplet’ earthquakes strike near Tohoku in Japan but a rupture gap remains” 

    1

    From temblor

    March 19, 2022

    Shinji Toda, Ph.D., IRIDeS, Tohoku University (東北大学](JP)
    Ross S. Stein, Ph.D., Temblor, Inc.

    Wednesday’s magnitude-7.3 quake, which shook large parts of Honshu and knocked out power to Tokyo, is the latest in a series of large aftershocks from the 2011 Tohoku earthquake.

    On Wednesday, March 16, 2022, a magnitude-7.3 shock struck 40 kilometers (25 miles) off the Tohoku Prefecture coast, causing strong shaking and damage to infrastructure and buildings. Three people were killed and 180 injured. Strong shaking reached Sendai and the Tohoku coastal cities, and power was knocked out for roughly 12 hours across Kanto, 330 kilometers (200 miles) away. A Tohoku Shinkansen bullet train with about 80 passengers on board derailed, fortunately with no loss of life.

    This quake is just one of a series of large shocks to strike the Honshu coast in the last decade. These events are signs that Earth’s crust is readjusting itself after the magnitude-9.0 Great Tohoku earthquake in 2011.

    Twin quakes rupture

    Wednesday’s quake struck just 7 kilometers (12 miles) southwest of a magnitude-7.1 that struck a year before, on February 12, 2021. The 2021 event ruptured mostly southward, along a 45-kilometer (27-mile) section of fault within the subducting Pacific tectonic plate.

    1
    Map of the Pacific plate
    4 May 2015
    Alataristarion

    Wednesday’s event ruptured at a similar depth, but propagated to the north. The ruptured patches of these two quakes partially overlap. Wednesday’s earthquake essentially doubled the length of fault that ruptured in 2021 (the combined extent of blue and magenta shocks in figure below). Earthquakes that strike near one another in space and time — so called “twin” or “doublet” earthquakes — are surprisingly common worldwide (Kagan and Jackson, 1999). They likely occur when faults re-rupture after a previous quake failed to relieve all the accumulated stress.

    2
    he first 24 hours of aftershocks for three large intra-slab quakes that have struck the Tohoku coast since the Great Tohoku magnitude-9.0 shock in 2011, whose rupture surface lies to the right (east) of this map.

    Earthquakes in the subducting Pacific plate

    Both the 2021 and 2022 earthquakes occurred along faults within the Pacific plate, where it descends beneath the main Japanese island of Honshu. These faults are either tears that formed as the Pacific plate is bent downwards, or old faults in the ocean crust that are reactivated as the plate is compressed during subduction. Earthquakes that strike along these faults are called ‘intra-slab’ events and they occur in subduction zones around the world. Events can be as large as magnitude-8.0. Although they often are not as devastating as the largest megathrust earthquakes, they can cause tsunamis and widespread damage.

    In contrast, the 2011 magnitude-9.1 Tohoku event was a “megathrust” earthquake, which struck 120 kilometers (70 miles) to the northeast of Wednesday’s epicenter. During the 2011 event, the Pacific plate slid under Honshu about 30 meters (100 feet) in the span of 200 seconds.

    Triplets leave a rupture gap

    But there’s more to the story, because a month after the 2011 Tohoku earthquake, a magnitude-7.1 intra-slab earthquake struck, 60 kilometers (36 miles) north of Wednesday’s epicenter (Ohta et al, 2011). That event ruptured a 30-km tear in the Pacific plate. The southern end of that rupture ends about 30 kilometers (20 miles) north of the ruptured area of Wednesday’s quake. Between these sections that has not ruptured in a major way in recent history.

    Earthquakes are promoted when a nearby shock deforms the surrounding crust in such a matter as to either unclamp a fault, or increases its shear stress; this is called the Coulomb hypothesis. When we calculate the areas in which stress increased following these three recent earthquakes, the gap lights up in red: It has been brought significantly closer to failure, and so is a likely candidate for a future earthquake in this sequence. But there are also other areas, such as to the north of the 2011 M 7.1 shock, where failure is also promoted.

    3
    The Coulomb stress imparted by the three intra-slab events since 2011. The imparted stress is very high in the apparent gap between the 2011 and 2022 events, but it is also high surrounding these ruptures. This is an idealized view of the surrounding faults, which assumes they are all roughly parallel to the three past ruptures.

    But we know that faults are not simple, parallel surfaces as assumed in the figure above. Where we have the best data and field evidence, faults have a diversity of lengths and orientations on many scales, and are even sometimes described as a fractal distribution. So, how can we capture this natural complexity in our forecast models? We do so by using past shocks, even tiny ones, to tell us where faults are, and how they are oriented.

    We show a messier — but we believe more accurate — picture of the stress imparted on faults by the three intra-slab earthquakes in the figure below. We represent the orientation of faults on which past earthquakes have occurred by beachballs. Red beachballs indicate faults were brought closer to failure — the point at which an earthquake occurs. Blue beachballs indicate faults inhibited from failure (Toda and Stein, 2021). A group of red beachballs to the north of Wednesday’s event is apparent, reinforcing our view that this gap is the most likely candidate for the next shock in the sequence, should it continue. But there is plenty of red to the southeast of the 2021 and 2022 ruptures as well. Fortunately, if an earthquake were to strike in the areas southeast of the recent ruptures, shaking in coastal communities would be less than if a quake closer.

    4
    The stress imparted by the three intra-slab quakes on the surrounding faults, as identified by past earthquake focal mechanisms (beachballs). Red beachballs are likely sites for subsequent shocks.

    Shaking reproducibility

    The three recent intra-slab shocks, each about 50 kilometers (30 miles) offshore and about 60 kilometers (35 miles) deep, provide a rare natural experiment on the reproducibility of strong shaking from one quake to the next. The Japan Meteorological Agency [気象庁](JP) operates a dense network of shaking intensity sensors throughout the country. The intensity records of the three events, shown below, are remarkably consistent, with a similar distribution of shaking and roughly the same number of peak shaking records (JMA Intensity 6+, which corresponds to a peak ground acceleration of about 0.5 g, the level at which major damage is expected). This means that we can forecast the shaking with some confidence. Of course, had these shocks been shallower or closer to the coast, the shaking and damage would have been much higher.

    But there is a catch. The intensity meters measure the peak shaking, not how long it lasts. The shaking intensities recorded by the 2011 magnitude-9.1 Tohoku earthquake are greater than for the 2021-2022 shocks, but only by about 15-50%, even though the magnitude-9.1 was almost 1,000 times larger than the recent event. The difference lies in the duration of strong shaking, which lasted for about three minutes in the Tohoku quake, and just 15 seconds for the magnitude-7 shocks. Bend a paper clip once, and it will be fine. Bend it back and forth ten times, and it breaks: long durations cause buildings to fatigue.

    4
    The shaking intensities for the three M 7.1-7.3 shocks, each about 50 km offshore and about 60 kilometers deep, are all very similar to each other. This is good news for our ability to model and forecast shaking and the damage it causes.

    Why the flurry of shocks?

    Although it seems remarkable that the Tohoku coastal region has been hit by three large shocks since the 2011 quake, in our view, they are all aftershocks of the Tohoku earthquake (we show evidence for this in Toda and Stein, 2021). In our judgment, more quakes are likely, albeit at a decreasing rate, for decades.

    References

    Y. Y. Kagan and D. D. Jackson (1999), Worldwide doublets of large shallow earthquakes, Bull. Seismol. Soc. Amer., 89, 1147-1155.

    Yusaku Ohta, Satoshi Miura, Mako Ohzono, Saeko Kita, Takeshi Iinuma, Tomotsugu Demachi, Kenji Tachibana, Takashi Nakayama, Satoshi Hirahara, Syuichi Suzuki, Toshiya Sato, Naoki Uchida, Akira Hasegawa, and Norihito Umino (2011), Large intraslab earthquake (2011 April 7, M 7.1) after the 2011 off the Pacific coast of Tohoku Earthquake (M 9.0): Coseismic fault model based on the dense GPS network data, Earth Planets Space, 63, 1207–1211.

    Toda, S., Stein, R.S. (2021), Recent large Japan quakes are aftershocks of the 2011 Tohoku Earthquake, Temblor, http://doi.org/10.32858/temblor.175

    See the full article https://temblor.net/earthquake-insights/triplet-earthquakes-strike-near-tohoku-japan-but-a-rupture-gap-remains-13983/ .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    _____________________________________________________________________________________

    Earthquake Alert

    1

    Earthquake Alert

    Earthquake Network projectEarthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    3
    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

    QuakeAlertUSA

    1

    About Early Warning Labs, LLC

    Early Warning Labs, LLC (EWL) is an Earthquake Early Warning technology developer and integrator located in Santa Monica, CA. EWL is partnered with industry leading GIS provider ESRI, Inc. and is collaborating with the US Government and university partners.

    EWL is investing millions of dollars over the next 36 months to complete the final integration and delivery of Earthquake Early Warning to individual consumers, government entities, and commercial users.

    EWL’s mission is to improve, expand, and lower the costs of the existing earthquake early warning systems.

    EWL is developing a robust cloud server environment to handle low-cost mass distribution of these warnings. In addition, Early Warning Labs is researching and developing automated response standards and systems that allow public and private users to take pre-defined automated actions to protect lives and assets.

    EWL has an existing beta R&D test system installed at one of the largest studios in Southern California. The goal of this system is to stress test EWL’s hardware, software, and alert signals while improving latency and reliability.

    Earthquake Early Warning Introduction

    The United States Geological Survey (USGS), in collaboration with state agencies, university partners, and private industry, is developing an earthquake early warning system (EEW) for the West Coast of the United States called ShakeAlert. The USGS Earthquake Hazards Program aims to mitigate earthquake losses in the United States. Citizens, first responders, and engineers rely on the USGS for accurate and timely information about where earthquakes occur, the ground shaking intensity in different locations, and the likelihood is of future significant ground shaking.

    The ShakeAlert Earthquake Early Warning System recently entered its first phase of operations. The USGS working in partnership with the California Governor’s Office of Emergency Services (Cal OES) is now allowing for the testing of public alerting via apps, Wireless Emergency Alerts, and by other means throughout California.

    ShakeAlert partners in Oregon and Washington are working with the USGS to test public alerting in those states sometime in 2020.

    ShakeAlert has demonstrated the feasibility of earthquake early warning, from event detection to producing USGS issued ShakeAlerts ® and will continue to undergo testing and will improve over time. In particular, robust and reliable alert delivery pathways for automated actions are currently being developed and implemented by private industry partners for use in California, Oregon, and Washington.

    Earthquake Early Warning Background

    The objective of an earthquake early warning system is to rapidly detect the initiation of an earthquake, estimate the level of ground shaking intensity to be expected, and issue a warning before significant ground shaking starts. A network of seismic sensors detects the first energy to radiate from an earthquake, the P-wave energy, and the location and the magnitude of the earthquake is rapidly determined. Then, the anticipated ground shaking across the region to be affected is estimated. The system can provide warning before the S-wave arrives, which brings the strong shaking that usually causes most of the damage. Warnings will be distributed to local and state public emergency response officials, critical infrastructure, private businesses, and the public. EEW systems have been successfully implemented in Japan, Taiwan, Mexico, and other nations with varying degrees of sophistication and coverage.

    Earthquake early warning can provide enough time to:

    Instruct students and employees to take a protective action such as Drop, Cover, and Hold On
    Initiate mass notification procedures
    Open fire-house doors and notify local first responders
    Slow and stop trains and taxiing planes
    Install measures to prevent/limit additional cars from going on bridges, entering tunnels, and being on freeway overpasses before the shaking starts
    Move people away from dangerous machines or chemicals in work environments
    Shut down gas lines, water treatment plants, or nuclear reactors
    Automatically shut down and isolate industrial systems

    However, earthquake warning notifications must be transmitted without requiring human review and response action must be automated, as the total warning times are short depending on geographic distance and varying soil densities from the epicenter.

     
  • richardmitnick 10:35 pm on January 26, 2022 Permalink | Reply
    Tags: "Northern Taiwan starts the new year with a jolt", , , , , , temblor   

    From temblor: “Northern Taiwan starts the new year with a jolt” 

    1

    From temblor

    January 26, 2022
    Wei-An Chen, B.S.
    Chung-Han Chan, Ph.D.
    Earthquake Disaster & Risk Evaluation and Management Center (E-DREaM)

    An offshore magnitude-6.0 earthquake on January 3 rattled the Taipei metropolitan area, but cities closer to the epicenter felt only light shaking.

    A magnitude-6.0 earthquake struck off the east coast of Taiwan on January 3, 2022, showing that faults are not going to take a break even for new year holidays.

    Shaking was felt throughout the island’s northern cities, reminding Taiwanese that they are living on a seismically active island. Scientists are constantly working to better understand earthquakes to help mitigate losses from strong shaking.

    January’s earthquake took place in the Ryukyu subduction system, where the Philippine Sea Plate subducts to the North, beneath the Eurasia Plate. The earthquake struck 19.4 kilometers below the surface, on the southernmost segment of the interface between these plates. The region is seismically active; more than 10 magnitude-6.0 and greater events have struck nearby in the past three decades.

    Patchy shaking patterns

    Ground shaking intensity usually decays with the distance from the origin of an earthquake. In the case of January’s earthquake, however, shaking was patchy. For instance, Taipei City — 130 kilometers away from the epicenter — experienced ground shaking up to 30.6 gal (Modified Mercalli intensity IV). Yet, in Hualien City, only 58 kilometers (36 miles) away from the earthquake, shaking reached only around 7.9 gal.

    1
    The distribution of peak ground acceleration (PGA) during the January 3 earthquake. The epicenter is denoted as a blue star. Stronger ground shaking was observed in northern Taiwan than to the south.

    This pattern is related to the ground beneath Taipei City, which is made up of soft sediments surrounded by hills made of stiff soil. Such “basins” trap seismic and amplify ground shaking, like a bowl of jelly. Similar effects were observed during the magnitude-7.1 Hualien earthquake in 2002. Despite striking far from Taipei City, this event caused high ground shaking intensity, resulting in significant damage; Hundreds of buildings were damaged and a tower crane working on Taipei 101 collapsed.

    Strong shaking was not restricted to Taipei. Shaking was significant throughout northern Taiwan, whereas in areas to the south, close to the epicenter, the effect was minimal. Such heterogeneous distribution could also be attributed to the earthquake itself. Earthquakes happen when a section of a fault slips. Such a “rupture” generally starts at a point and propagates along the boundary, as the area the slipped grows. The seismic waves traveling in the same direction as the propagating rupture are compressed and amplified, intensifying shaking. This phenomenon is also known as the “Doppler effect.” During the January 3 earthquake, slip on the fault propagated to the northwest with maximum slip of 26 centimeters (10 inches). The waves traveling towards northern Taiwan were therefore amplified.

    Seismologists noticed a similar effect during the magnitude-6.4 Meinong earthquake, which struck southern Taiwan in 2016. This event ruptured westward from the nucleation point, below the epicenter, causing stronger ground shaking and damage in that direction.

    Ryukyu Trench could host an even bigger earthquake

    GPS data collected on the northeast coast of Taiwan indicate that the Ryukyu subduction zone is locked, according to an analysis by Ya-Ju Hsu, a seismologist at the Institute of Earth Sciences, Academia Sinica, Taiwan. Along the boundary, frictional resistance is greater than the stress of the plates moving past one another. An earthquake occurs when that force overcomes friction.

    Seismological and geodetic evidence suggests that enough stress has built on the boundary to generate a magnitude-8.0 or larger megathrust earthquake. Such an earthquake could cause widespread damage from violent shaking and a major tsunami.

    Although earthquakes around magnitude 6.0, such as the one on January 3, sometimes take place in the subduction zone, the energy they release is negligible compared to that of a magnitude-8.0 event. After a smaller magnitude-6.0 event, there is still enough stress on the boundary for a magnitude-8.0 earthquake.

    2
    Shake map from a magnitude-8.0 scenario in the Ryukyu subduction zone. The maximum ground shaking might impact central Hualien County.

    To quantify the seismic hazard and risk from the subduction zone, scientists from National Central University [國立中央大學](TW), Sinotech Engineering Consultants, Inc., National Science and Technology Center for Disaster Reduction [ 國家災害防救科技中心](TW) and National Center for Research on Earthquake Engineering [國家地震工程研究中心](TW) worked together to simulate a ground shaking scenario for a future magnitude-8.0 earthquake along the Ryukyu subduction interface. The resulting shake map [above] shows that ground shaking would be severe in central Hualien County, due to its proximity to the interface. By further considering the distribution of buildings, population and infrastructure, researchers could take this analysis further and calculate losses from such an event, including the distribution of building, road, bridge and cell tower damage, fatalities, fires, electricity interruption and requirement of sheltering. This scenario became the basis for the drill on National Disaster Preparedness Day in September 2021.

    There is no doubt that the Ryukyu subduction system is one of the major threats to Taiwan. An event at the southernmost segment in this system could result in significant ground shaking along the eastern coast Taiwan and even the Taipei metropolitan area. Thus, it is crucial to boost awareness and fortify communities against major damage by enhancing buildings that are vulnerable to earthquake damage.

    References

    Hsu, Y. J., Ando, M., Yu, S. B., & Simons, M. (2012). The potential for a great earthquake along the southernmost Ryukyu subduction zone. Geophysical research letters, 39(14).
    Wu, Y. M., Liang, W. T., Mittal, H., Chao, W. A., Lin, C. H., Huang, B. S., & Lin, C. M. (2016). Performance of a low-cost earthquake early warning system (P-alert) during the 2016 ML 6.4 Meinong (Taiwan) earthquake. Seismological Research Letters, 87(5), 1050-1059.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    _____________________________________________________________________________________

    Earthquake Alert

    1

    Earthquake Alert

    Earthquake Network project Earthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    3
    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

    QuakeAlertUSA

    1

    About Early Warning Labs, LLC

    Early Warning Labs, LLC (EWL) is an Earthquake Early Warning technology developer and integrator located in Santa Monica, CA. EWL is partnered with industry leading GIS provider ESRI, Inc. and is collaborating with the US Government and university partners.

    EWL is investing millions of dollars over the next 36 months to complete the final integration and delivery of Earthquake Early Warning to individual consumers, government entities, and commercial users.

    EWL’s mission is to improve, expand, and lower the costs of the existing earthquake early warning systems.

    EWL is developing a robust cloud server environment to handle low-cost mass distribution of these warnings. In addition, Early Warning Labs is researching and developing automated response standards and systems that allow public and private users to take pre-defined automated actions to protect lives and assets.

    EWL has an existing beta R&D test system installed at one of the largest studios in Southern California. The goal of this system is to stress test EWL’s hardware, software, and alert signals while improving latency and reliability.

    Earthquake Early Warning Introduction

    The United States Geological Survey (USGS), in collaboration with state agencies, university partners, and private industry, is developing an earthquake early warning system (EEW) for the West Coast of the United States called ShakeAlert. The USGS Earthquake Hazards Program aims to mitigate earthquake losses in the United States. Citizens, first responders, and engineers rely on the USGS for accurate and timely information about where earthquakes occur, the ground shaking intensity in different locations, and the likelihood is of future significant ground shaking.

    The ShakeAlert Earthquake Early Warning System recently entered its first phase of operations. The USGS working in partnership with the California Governor’s Office of Emergency Services (Cal OES) is now allowing for the testing of public alerting via apps, Wireless Emergency Alerts, and by other means throughout California.

    ShakeAlert partners in Oregon and Washington are working with the USGS to test public alerting in those states sometime in 2020.

    ShakeAlert has demonstrated the feasibility of earthquake early warning, from event detection to producing USGS issued ShakeAlerts ® and will continue to undergo testing and will improve over time. In particular, robust and reliable alert delivery pathways for automated actions are currently being developed and implemented by private industry partners for use in California, Oregon, and Washington.

    Earthquake Early Warning Background

    The objective of an earthquake early warning system is to rapidly detect the initiation of an earthquake, estimate the level of ground shaking intensity to be expected, and issue a warning before significant ground shaking starts. A network of seismic sensors detects the first energy to radiate from an earthquake, the P-wave energy, and the location and the magnitude of the earthquake is rapidly determined. Then, the anticipated ground shaking across the region to be affected is estimated. The system can provide warning before the S-wave arrives, which brings the strong shaking that usually causes most of the damage. Warnings will be distributed to local and state public emergency response officials, critical infrastructure, private businesses, and the public. EEW systems have been successfully implemented in Japan, Taiwan, Mexico, and other nations with varying degrees of sophistication and coverage.

    Earthquake early warning can provide enough time to:

    Instruct students and employees to take a protective action such as Drop, Cover, and Hold On
    Initiate mass notification procedures
    Open fire-house doors and notify local first responders
    Slow and stop trains and taxiing planes
    Install measures to prevent/limit additional cars from going on bridges, entering tunnels, and being on freeway overpasses before the shaking starts
    Move people away from dangerous machines or chemicals in work environments
    Shut down gas lines, water treatment plants, or nuclear reactors
    Automatically shut down and isolate industrial systems

    However, earthquake warning notifications must be transmitted without requiring human review and response action must be automated, as the total warning times are short depending on geographic distance and varying soil densities from the epicenter.

     
  • richardmitnick 11:06 am on January 20, 2022 Permalink | Reply
    Tags: "Hunga-Tonga-Hunga-Ha’apai in the south Pacific erupts violently", , , , temblor,   

    From temblor: “Hunga-Tonga-Hunga-Ha’apai in the south Pacific erupts violently” 

    1

    From temblor

    January 18, 2022
    Marie Edmonds, Ph.D., The University of Cambridge (UK)

    The Hunga-Tonga-Hunga-Ha’apai volcano, 40 miles (65 kilometers) north of Tongatapu, Tonga, erupted on January 15 at 5:14 p.m. local time, triggering tsunami waves that swept across the Pacific. The energy released in the eruption was equivalent to a magnitude-5.8 earthquake at the surface, according to the U.S. Geological Survey. The powerful eruption was captured on satellite images, which show a shock wave and a rapidly expanding ash cloud that reached 12 miles (20 kilometers) into the atmosphere.

    1
    The expanding ash cloud from the eruption of the Hunga-Tonga-Hunga-Ha’apai volcano on January 15. Credit: The National Oceanic and Atmospheric Administration (US), Public Domain, via Wikimedia Commons.

    News of the immediate impact of the eruption on the Tongan islands has been slow to emerge because internet communications have been entirely cut off by the eruption. It is likely, however, that the islands have experienced many inches of ash fall as well as damage from the tsunami, which inundated coastal areas and reached a height of 2.7 feet (83 centimetres) in Nuku’alofa, according to The Pacific Tsunami Warning Center (US).

    2
    The island of Tongatapu and the nearby smaller islands – all part of the Kingdom of Tonga archipelago in the southern Pacific Ocean – are pictured in this Sentinel-2A image from May 23, 2016. Contains modified Copernicus Sentinel data (2016), processed by ESA,CC BY-SA 3.0 IGO, via Wikimedia Commons

    ESA Copernicus Sentinel-2.

    Tsunami waves reached 3.6 feet (1.1 meters) along the northeastern coastline of Japan at a port in Kuji, Iwate (Source: Japan Meteorological Agency) and up to 3.6 feet (1.1 meters) in Port San Luis, California (Source: NOAA). In northern Peru, two people drowned when waves inundated a beach in the Lambayeque region.

    Explosion detected on the other side of the world

    The eruption was heard in New Zealand. The shock wave was violent enough to shake houses in Fiji, more than 450 miles (720 kilometers) away from Tonga.

    Pressure surges from the atmospheric perturbation caused by the eruption were felt right across the world. Atmospheric pressure fluctuations have been reported in New Zealand, the U.S., Brazil, Japan and Europe. More than 14 hours after the eruption, The Meteorological Office (UK) picked up several pressure waves, more than 10,000 miles away from the volcano. The agency described the waves as “like dropping a pebble in a still pond and seeing the ripples.”

    The eruption was so powerful it destroyed the subaerial part of the volcano that had been built up in successive eruptions since 2015, according to the Smithsonian’s Global Volcanism Program. Radar images of the island acquired by The European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne][Europäische Weltraumorganisation](EU)’s Sentinel-2 satellite show that the island has largely disappeared following the eruption; only the far southwestern and northeastern tips of the island remain.

    3
    Before (left) and after (right) radar images of the Hunga Tonga-Hunga Haapai Volcano, Tonga, January 2 and 17, 2022. Credit: Copernicus/ESA/Sentinal Hub.

    Long-term climate impacts unlikely

    The ash produced by the eruption has now dispersed from the caldera, but the finest particles are likely still aloft high in the atmosphere and will remain there for months or even years.

    The eruption also produced around 0.4 teragrams of sulfur dioxide (SO2), according to spectrometer data from ESA’s Sentinel 5P satellite.

    ESA Copernicus Sentinel-5P.

    Past large explosive eruptions have typically been associated with global cooling. SO2 injected into the stratosphere — the second layer of the atmosphere — forms sulfate aerosol when it reacts with water, which absorbs and scatters incoming radiation from the sun, thereby cooling the Earth’s surface.

    The 1991 eruption of Pinatubo Volcano in the Philippines emitted around 18-19 teragrams of SO2, which caused cooling of a few tenths of a degree for a few years. It is unlikely that the SO2 emitted from the Hunga-Tonga-Hunga-Ha’apai eruption will significantly impact the climate.

    One volcano in a chain

    The Hunga-Tonga-Hunga-Ha’apai volcano lies along the Tonga-Kermedec Arc, where two tectonic plates in the southwest Pacific converge. This volcano is one of a chain of largely submarine volcanoes that extend all the way from New Zealand in the southwest to Fiji in the north-northeast. Here, the Pacific plate subducts beneath the Indo-Australian plate. As it sinks, the Pacific Plate heats up, releasing fluids into the overlying rocks, which causes them to melt. The magma rises into the overlying crust and some erupts at the surface. Eruptions from subduction zone volcanoes are notoriously explosive because magmas there are sticky and contain large quantities of dissolved water from the mantle, which is the explosion’s “fuel.”

    4
    Map of the Kermadec and Tonga subduction trench. Credit: Nwbeeson, CC BY-SA 4.0, via Wikimedia Commons.

    For submarine volcanic eruptions however, there is an added ingredient that causes them to be extra-violent. During large volcanic eruptions a caldera, or large depression on the surface, can form due to the void left in the ground by the erupted magma. Calderas that form on the seafloor can cause tsunamis and large earthquakes when large rock masses sink during the eruption.

    Seawater can flow into the faults and fractures that form around the edges of the caldera. If water comes into contact with hot magma, it flash boils into steam, which expands rapidly, adding to the explosive power of an eruption. Such eruptions are termed “hydrovolcanic.” They generate powerful base surges — or pyroclastic flows — that expand out from the base of the eruption column, and can travel long distances. A famous example is the 1883 eruption of Krakatoa Volcano in Indonesia. The sound of the explosion was heard 1,800 miles (3,000 kilometers) away. Large tsunami waves and pyroclastic surges that travelled 25 miles (40 kilometers) over the surface of the sea killed more than 36,000 people.

    Geologists studying the Hunga-Tonga-Hunga-Ha’apai volcano have uncovered its few-thousand-year-long history of eruptions just like the one that occurred on January 15. The volcano erupted explosively in 2009 and in 2014-2015, producing ‘Surtseyan’ eruptions — a smaller magnitude explosive eruption produced by the interaction of magma and seawater. The precise magnitude of this latest eruption will be known once the height of the eruption column as well as the volume of erupted material is estimated, but it is certainly one of the most significant eruptions of the 21st century thus far.

    5
    NASA’s Terra satellite on December 29, 2014, showing a white plume rising over the undersea volcano Hunga Ha’apai, near Hunga Tonga in the South Pacific. Discolored water suggests an underwater release of gases and rock by the eruption. Credit: NASA, CC0, via Wikimedia Commons.

    National Aeronautics Space Agency (US)Terra satellite.

    Answers still to come

    There are many questions to be answered over the coming weeks and months about the mechanisms and impacts of this eruption. Immediate questions concern the fate of the residents of Tonga, who are contending with the enormous challenges of the aftermath of the eruption and tsunami, including missing loved ones, enormous infrastructure damage, thick ash cover, contaminated drinking supplies and a lack of basic medical and communication services.

    There will be detailed studies of the geophysical signals accompanying the eruption and the period leading up to it to better understand how the eruption was triggered and its magnitude. Scientists will be particularly interested in infrasound, satellite-based data and eventually will study the volcanic deposits and landforms produced. In particular, scientists will seek to understand the geological sequence of events that led to the simultaneous explosion and tsunami that had such wide-ranging effects across the Pacific Ocean.

    References

    Guo, S., Bluth, G. J., Rose, W. I., Watson, I. M., & Prata, A. J. (2004). Re‐evaluation of SO2 release of the 15 June 1991 Pinatubo eruption using ultraviolet and infrared satellite sensors. Geochemistry, Geophysics, Geosystems, 5(4).

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    _____________________________________________________________________________________

    Earthquake Alert

    1

    Earthquake Alert

    Earthquake Network project Earthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    3
    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

    QuakeAlertUSA

    1

    About Early Warning Labs, LLC

    Early Warning Labs, LLC (EWL) is an Earthquake Early Warning technology developer and integrator located in Santa Monica, CA. EWL is partnered with industry leading GIS provider ESRI, Inc. and is collaborating with the US Government and university partners.

    EWL is investing millions of dollars over the next 36 months to complete the final integration and delivery of Earthquake Early Warning to individual consumers, government entities, and commercial users.

    EWL’s mission is to improve, expand, and lower the costs of the existing earthquake early warning systems.

    EWL is developing a robust cloud server environment to handle low-cost mass distribution of these warnings. In addition, Early Warning Labs is researching and developing automated response standards and systems that allow public and private users to take pre-defined automated actions to protect lives and assets.

    EWL has an existing beta R&D test system installed at one of the largest studios in Southern California. The goal of this system is to stress test EWL’s hardware, software, and alert signals while improving latency and reliability.

    Earthquake Early Warning Introduction

    The United States Geological Survey (USGS), in collaboration with state agencies, university partners, and private industry, is developing an earthquake early warning system (EEW) for the West Coast of the United States called ShakeAlert. The USGS Earthquake Hazards Program aims to mitigate earthquake losses in the United States. Citizens, first responders, and engineers rely on the USGS for accurate and timely information about where earthquakes occur, the ground shaking intensity in different locations, and the likelihood is of future significant ground shaking.

    The ShakeAlert Earthquake Early Warning System recently entered its first phase of operations. The USGS working in partnership with the California Governor’s Office of Emergency Services (Cal OES) is now allowing for the testing of public alerting via apps, Wireless Emergency Alerts, and by other means throughout California.

    ShakeAlert partners in Oregon and Washington are working with the USGS to test public alerting in those states sometime in 2020.

    ShakeAlert has demonstrated the feasibility of earthquake early warning, from event detection to producing USGS issued ShakeAlerts ® and will continue to undergo testing and will improve over time. In particular, robust and reliable alert delivery pathways for automated actions are currently being developed and implemented by private industry partners for use in California, Oregon, and Washington.

    Earthquake Early Warning Background

    The objective of an earthquake early warning system is to rapidly detect the initiation of an earthquake, estimate the level of ground shaking intensity to be expected, and issue a warning before significant ground shaking starts. A network of seismic sensors detects the first energy to radiate from an earthquake, the P-wave energy, and the location and the magnitude of the earthquake is rapidly determined. Then, the anticipated ground shaking across the region to be affected is estimated. The system can provide warning before the S-wave arrives, which brings the strong shaking that usually causes most of the damage. Warnings will be distributed to local and state public emergency response officials, critical infrastructure, private businesses, and the public. EEW systems have been successfully implemented in Japan, Taiwan, Mexico, and other nations with varying degrees of sophistication and coverage.

    Earthquake early warning can provide enough time to:

    Instruct students and employees to take a protective action such as Drop, Cover, and Hold On
    Initiate mass notification procedures
    Open fire-house doors and notify local first responders
    Slow and stop trains and taxiing planes
    Install measures to prevent/limit additional cars from going on bridges, entering tunnels, and being on freeway overpasses before the shaking starts
    Move people away from dangerous machines or chemicals in work environments
    Shut down gas lines, water treatment plants, or nuclear reactors
    Automatically shut down and isolate industrial systems

    However, earthquake warning notifications must be transmitted without requiring human review and response action must be automated, as the total warning times are short depending on geographic distance and varying soil densities from the epicenter.

     
  • richardmitnick 12:56 pm on January 15, 2022 Permalink | Reply
    Tags: "Strong earthquake increases seismic hazard in Qinghai in China", , , , , temblor   

    From temblor : “Strong earthquake increases seismic hazard in Qinghai in China” 

    1

    From temblor

    January 13, 2022

    By Zhigang Peng, Ph.D., School of Earth and Atmospheric Sciences, The Georgia Institute of Technology (US), Jing Liu-Zeng, Ph.D., Tianjin University[天津大學](CN), Yangfan Deng, Ph.D., The Chinese Academy of Sciences [中国科学院](CN) Center for Excellence in Deep Earth Science, Guangzhou, China, Shinji Toda, Ph.D., International Research Institute of Disaster Science, Tohoku University [東北大学](JP).

    A powerful magnitude-6.6 earthquake occurred in the Qinghai province in Western China on January 7, 2022 (Figure 1). The quake struck at 1:45 a.m. local time in a remote region of Menyuan county. It was the largest earthquake in China since the magnitude-7.3 Maduo earthquake in the same province in May 2021. The Menyuan earthquake was widely felt in surrounding regions and caused temporary halts of several high-speed rail lines. But the region is sparsely populated, and only minor injuries and property damage were reported.

    1
    Figure 1. Active faults in the northeastern Tibetan plateau and the focal mechanism of the most recent Menyuan earthquake in Northwestern China. The inset marks the map in a larger map of Tibetan Plateau. HYF: Haiyuan Fault; ATF: Altyn Tagh Fault; KF: Kunlun fault; XHF: Xianshuihe Fault. Credit: Wenqian Yao.

    Tectonic Environment

    The earthquake occurred in the northeastern margin of the Tibetan Plateau, which was created by the collision between the Eurasian and Indian tectonic plates. Near the recent epicenter, tectonic movement is mostly accommodated by a combination of thrust faults and left-lateral strike-slip fault systems such as the Altyn Tagh, the Kunlun and Haiyuan faults (Figure 1). The most recent Menyuan earthquake occurred on the Lenglongling (meaning “Cold Dragon Ridge” in Chinese) Fault, which is the western branch of the Haiyuan fault. This region is seismically active. Moderate-sized earthquakes occurred in 1986 and 2016 within 40 kilometers to the east of the recent epicenter. Both preceding events involved thrust motion, and so were different from this strike-slip event. All three quakes occurred in a “restraining bend” of the Haiyuan fault, meaning that there is compression straddling the fault, leading to a combination of thrusting and strike-slip motion.

    Compared with the 2016 event, the 2022 earthquake started in the same bend or jog, but the rupture appeared to propagate further to the west along the main strike-slip fault, producing roughly 22-kilometer surface ruptures on the ground. Further to the east, two roughly magnitude-8.0 earthquakes occurred in the past century (the 1920 Haiyuan and 1927 Gulang earthquakes), causing significant damage and casualties (Figure 2). The great 1920 Haiyuan earthquake also triggered numerous landslides in the terrain mantled by loess — windblown sand or dust, often derived from glacier deposits. Between these great earthquakes is a 260-kilometer-long segment of the Haiyuan Fault that has not ruptured in the past 1000 years (Liu-Zeng et al., 2007). The section is known as the “Tianzhu” seismic gap (Gaudemer et al. 1995) and could host large damaging earthquakes in the future.

    2
    Figure 2. Tectonic map and earthquake locations/focal mechanisms in the Northeastern Tibetan Plateau. The blue lines mark ruptures associated with previous large earthquakes and the red line mark the Tianzhu seismic gap. Modified after Deng et al. (2020).

    Mainshock Slip Patterns and Intensities

    The mainshock focal mechanism is primarily left-lateral, which is consistent with the tectonic movement of the nearby Lenglongling Fault. Rapid finite fault modeling based on long-period teleseismic waves has shown that the mainshock ruptured in both directions along the fault from its nucleation point, with more slip to the east (Figure 3). In contrast, back-projections of short-period teleseismic P waves suggest that the mainshock ruptured primarily to the northwest (Figure 4). This is perhaps not surprising because these approaches use different techniques and frequency bands, and hence they are mostly sensitive to different types of earthquake rupture. For example, long-period finite fault modeling results likely correspond to smooth ruptures that produce significant fault slip. In comparison, short-period back-projection results likely image seismic ruptures on a relatively rough patch that produce significant high-frequency shaking. This is qualitatively consistent with the near-field strong motion and intensity recordings (Figure 5), showing high peak accelerations primarily around the mainshock epicenter and to the northwest direction.

    3
    Figure 3. A preliminary finite fault modeling result for the 2022 magnitude-6.6 Menyuan mainshock based on teleseismic P waves. The inset marks the fault strike with respect to north. Modified from results by Weiming Wang.

    4
    Figure 4. Mainshock rupture propagation results based on back-projection stack of teleseismic P waves recorded at broadband stations in Europe. Timing (color of circles) and amplitude (size of circles) for the stack with the maximum correlation at each time step in the map view. Red and black stars represent the epicenter of the 2022 Mw 6.6 Qinghai earthquake determined by the China Earthquake Networks Center (CENC), and United States Geological Survey (USGS), respectively. Gray circles indicate the locations of aftershocks that occurred within one day following the main shock (from Lihua Fang). Red lines represent traces of faults and province boundaries, respectively. Credit: Dun Wang.

    5
    Figure 5. Near-field peak acceleration map for the M6.6 Menyuan mainshock. Modified from a figure provided by Qiang Ma.

    Aftershocks and Surface Ruptures

    As of January 13, 2022, at 8 a.m. Beijing time, more than 5000 aftershocks have been identified (Figure 6). The largest aftershock has a moment magnitude of 5.3. Relocated aftershocks extended about 40 kilometers to both sides of the mainshock epicenter. To the west, the aftershocks illuminate a fault striking nearly east-west, which is consistent with a rupture on the similarly oriented Tuolaishan Fault (TLSF). To the east, aftershocks mostly follow the local strike of the Lenglongling fault (LLLF). There appears to be a few kilometers gap between the aftershocks of the 2022 magnitude-6.6 mainshock and those of the 2016 magnitude-5.9 mainshock. The 2016 event was a thrust event that likely ruptured the Northern Lenglongling Fault (NLLLF) (Liu et al., 2019), rather than the left-lateral Lenglongling Fault that ruptured in the most recent event.

    6
    Figure 6. A comparison of relocated aftershocks following the 2022 M6.6 and 2016 M5.9 mainshocks. The aftershock locations following the 2022 mainshock were provided by Lihua Fang. LLLF: Lenglongling fault; NLLLF: Northern Lenglongling fault; TLSF: Tuolaishan fault. The 2016 aftershock locations were from Liu et al. (2019). Credit: Yangfan Deng.

    Coulomb Stress Transfers and Seismic Hazard

    9
    Figure 9. Coulomb stress changes due to the 2016 Mw5.9 earthquake resolved onto (a) the left-lateral faults parallel to the 2022 rupture plane and (b) onto the 2022 fault plane of the finite fault model of Wang et al. (Figure 3). We implemented a simple uniform slip model of the NW-striking blind thrust for the 2016 earthquake based on the USGS CMT and Wells and Coppersmith (1994) empirical relation. Credit: Shinji Toda.

    Due to their proximity and timing, we explore whether the 2016 magnitude-5.9 event promoted the 2022 magnitude-6.6 earthquake by static stress transfer. As shown in Figure 9, the 2016 magnitude-5.9 earthquake imparted up to 0.4 bar (0.04 MPa) of stress on the fault plane that ruptured during the 2022 earthquake. The calculation was done using the Coulomb 3.3 Software (Toda et al., 2011), with an effective coefficient of friction of 0.4. Similarly, we also compute the Coulomb stress changes on both left-lateral faults and northwest-trending thrust faults due to the combined effects of the 2016 and 2022 events (Figure 10). As expected, both events produced positive stress changes on nearby faults, suggesting an increased likelihood of future damaging earthquakes in these regions. In particular, the 2022 earthquake may have brought the unbroken sections to the west (i.e., the Tuolaishan Fault) and east (i.e., the Lenglongling Fault) of the 2022 surface ruptures several bars closer to failure. Indeed, so far, several roughly magnitude-5.0 aftershocks have occurred, suggesting seismic hazard in these sections is relatively high.

    10
    Figure 10. The maximum Coulomb stress imparted by both 2016 and 2022 events for (a) WNW-striking left-lateral faults, and (b) NW-trending thrust faults at a depth range of 5-15 km. The finite fault model by Wang et al. (Figure 3) is used for the 2022 earthquake stress transfer. Credit: Shinji Toda.

    The recent earthquake struck in an area previously highlighted by the China Earthquake Administration as having a high probability of a magnitude-6.0 or greater earthquake (Xu et al., 2017). This earthquake provides a glimmer of hope for the scientists engaging in long- and short-term earthquake forecasting in China.

    Acknowledgement

    We thank Drs. Lihua Fang at Institute of Geophysics, China Earthquake Administration, Dun Wang at Chinese University of Geosciences, Wuhan, Weiming Wang at Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Qiang Ma at Institute Engineering Mechanics, China Earthquake Administration, and Jie Gao at China Earthquake Disaster Prevention Center for providing their preliminary results and field photos that are included in this news report. We also thank Dr. Weqian Yao at Tianjing University for making Figure 1.

    References

    Deng, Y., Peng, Z., & Liu-Zeng, J. (2020), Systematic search for repeating earthquakes along the Haiyuan fault system in Northeastern Tibet, Journal of Geophysical Research: Solid Earth, 125(7), e2020JB019583, https://doi.org/10.1029/2020JB019583.

    Gaudemer, Y., Tapponnier, P., Meyer, B., Peltzer, G., Shunmin, G., Zhitai, C., et al. (1995). Partitioning of crustal slip between linked, active faults in the eastern Qilian Shan, and evidence for a major seismic gap, the ‘Tianzhu gap’, on the western Haiyuan Fault, Gansu (China). Geophysical Journal International, 120(3), 599–645. https://doi.org/10.1111/j.1365-246X.1995.tb01842.x

    Liu, M., Li, H., Peng, Z., Ouyang, L., Ma, Y., Ma, J., Liang, Z., & Huang, Y. (2019), Spatial-temporal distribution of early aftershocks following the 2016 Ms 6.4 Menyuan, Qinghai, China Earthquake, Tectonophysics, 766, 469-479, https://doi.org/10.1016/j.tecto.2019.06.022.

    Liu-Zeng, J., Y. Klinger, X. Xu, C. Lasserre, G. Chen, W. Chen, P. Tapponnier, and B. Zhang, 2007. Millennial Recurrence of Large Earthquakes on the Haiyuan Fault near Songshan, Gansu Province, China, Bulletin of Seismological Society of America, 97 (1B): 14-34

    Toda, S. R. S. Stein, V. Sevilgen, and J. Lin (2011) Coulomb 3.3 graphic-rich deformation and stress-change software for earthquake, tectonic, and volcano research and teaching —user guide: U.S. Geological Survey Open-File Report 2011–1060, 63 p., available at https://pubs.usgs.gov/of/2011/1060/.

    Wells, D.L. and Coppersmith K.J. (1994), New Empirical Relationships among Magnitude, Rupture Length, Rupture width, Rupture Area, and Surface Displacement. Bulletin of the Seismological Society of America, 84, 974-1002.

    Xu, Xiwei, X. Wu, G. Yu, X. Tan, and K. Li (2017), Seismo-geological signatures for identifying M≥7.0 earthquake risk areas and their preliminary application in mainland China, Seismology and Geology, 39(2), doi:10.3969/j.isn.0253-4967.2017.02.001 (in Chinese).

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    _____________________________________________________________________________________

    Earthquake Alert

    1

    Earthquake Alert

    Earthquake Network project Earthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    3
    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

    QuakeAlertUSA

    1

    About Early Warning Labs, LLC

    Early Warning Labs, LLC (EWL) is an Earthquake Early Warning technology developer and integrator located in Santa Monica, CA. EWL is partnered with industry leading GIS provider ESRI, Inc. and is collaborating with the US Government and university partners.

    EWL is investing millions of dollars over the next 36 months to complete the final integration and delivery of Earthquake Early Warning to individual consumers, government entities, and commercial users.

    EWL’s mission is to improve, expand, and lower the costs of the existing earthquake early warning systems.

    EWL is developing a robust cloud server environment to handle low-cost mass distribution of these warnings. In addition, Early Warning Labs is researching and developing automated response standards and systems that allow public and private users to take pre-defined automated actions to protect lives and assets.

    EWL has an existing beta R&D test system installed at one of the largest studios in Southern California. The goal of this system is to stress test EWL’s hardware, software, and alert signals while improving latency and reliability.

    Earthquake Early Warning Introduction

    The United States Geological Survey (USGS), in collaboration with state agencies, university partners, and private industry, is developing an earthquake early warning system (EEW) for the West Coast of the United States called ShakeAlert. The USGS Earthquake Hazards Program aims to mitigate earthquake losses in the United States. Citizens, first responders, and engineers rely on the USGS for accurate and timely information about where earthquakes occur, the ground shaking intensity in different locations, and the likelihood is of future significant ground shaking.

    The ShakeAlert Earthquake Early Warning System recently entered its first phase of operations. The USGS working in partnership with the California Governor’s Office of Emergency Services (Cal OES) is now allowing for the testing of public alerting via apps, Wireless Emergency Alerts, and by other means throughout California.

    ShakeAlert partners in Oregon and Washington are working with the USGS to test public alerting in those states sometime in 2020.

    ShakeAlert has demonstrated the feasibility of earthquake early warning, from event detection to producing USGS issued ShakeAlerts ® and will continue to undergo testing and will improve over time. In particular, robust and reliable alert delivery pathways for automated actions are currently being developed and implemented by private industry partners for use in California, Oregon, and Washington.

    Earthquake Early Warning Background

    The objective of an earthquake early warning system is to rapidly detect the initiation of an earthquake, estimate the level of ground shaking intensity to be expected, and issue a warning before significant ground shaking starts. A network of seismic sensors detects the first energy to radiate from an earthquake, the P-wave energy, and the location and the magnitude of the earthquake is rapidly determined. Then, the anticipated ground shaking across the region to be affected is estimated. The system can provide warning before the S-wave arrives, which brings the strong shaking that usually causes most of the damage. Warnings will be distributed to local and state public emergency response officials, critical infrastructure, private businesses, and the public. EEW systems have been successfully implemented in Japan, Taiwan, Mexico, and other nations with varying degrees of sophistication and coverage.

    Earthquake early warning can provide enough time to:

    Instruct students and employees to take a protective action such as Drop, Cover, and Hold On
    Initiate mass notification procedures
    Open fire-house doors and notify local first responders
    Slow and stop trains and taxiing planes
    Install measures to prevent/limit additional cars from going on bridges, entering tunnels, and being on freeway overpasses before the shaking starts
    Move people away from dangerous machines or chemicals in work environments
    Shut down gas lines, water treatment plants, or nuclear reactors
    Automatically shut down and isolate industrial systems

    However, earthquake warning notifications must be transmitted without requiring human review and response action must be automated, as the total warning times are short depending on geographic distance and varying soil densities from the epicenter.

     
  • richardmitnick 8:32 pm on December 30, 2021 Permalink | Reply
    Tags: "Luzon in the Philippines sees sixth strong earthquake in five months", , , , , temblor   

    From temblor : “Luzon in the Philippines sees sixth strong earthquake in five months” 

    1

    From temblor

    December 21, 2021

    By Mario Aurelio, Director of the The University of the Philippines [Pamantasan ng Pilipinas or Unibersidad ng Pilipinas](PH) National Institute of Geological Sciences Sandra Donna Catugas, Structural Geology and Tectonics Laboratory at the University of Philippines National Institute of Geological Sciences
    John Agustin Escudero, Structural Geology and Tectonics Laboratory at the University of Philippines National Institute of Geological Sciences
    Alfredo Mahar Francisco Lagmay, Executive Director, University of the Philippines Resilience Institute-Nationwide Operational Assessment of Hazards Center (@nababaha)
    Giovanni A. Tapang, Dean of the University of the Philippines-Diliman College of Science

    On December 13, 2021, at 5:12 p.m. local time, the Batangas region in southern Luzon, Philippines, was hit by the fifth earthquake with a magnitude greater than 5.0 since a magnitude-6.6 tremor on July 24, 2021 (Aurelio et al., 2021a; 2021b; 2021c). Prior to this, four earthquakes with magnitude-5.8 (July 24 and August 13), 5.7 (September 27) and 5.2 (October 7) struck within a radius of 20 miles (30 kilometers) of the first July 24 event. This recurrence interval — an average of more than one strong earthquake every month — is too short to be neglected. This is either an unusually vigorous aftershock sequence, or an event comparable to a seismic swarm.

    Area of stress increase

    Using the fault responsible for generating the magnitude-6.6 earthquake of July 24, as the source fault, Coulomb stress transfer modeling indicates that the magnitude-5.5 tremor of December 13 falls within the lobe of increased stress when used as the receiver fault (Fig. 1). The 65-mile (104-kilometer) depth of the December tremor also plots approximately along the same fault plane, but four miles (seven kilometers) shallower than the July 24 event. These observations suggest that the first earthquake likely triggered the second.

    1
    Figure 1. Seismotectonics of six moderate magnitude, thrust-mechanism earthquakes (shown by beachballs) occurring in the same region in Batangas, southern Luzon, Philippines, within a period of five months (July 24 to December 13, 2021). Result of Coulomb stress change modeling shown. July 24 magnitude-6.6 as source; December 13 magnitude-5.5 as receiver. References: Jarvis et al., 2008 for SRTM topography; Weatherall et al., 2020 for bathymetry; Toda et al., 2011 for Coulomb stress transfer modeling; PHIVOLCS for earthquake data. GMT (Wessel and Smith, 1995) was used to generate the map. See text for more discussion. Credit: Aurelio, Catugas, Escudero, Lagmay,Tapang.

    The same triggering mechanism can explain three of the other recent magnitude-5.0 and larger events when each is used as the receiver fault (Aurelio et al., 2021a; 2021b), except for the magnitude-5.7 quake of September 27, which occurred in a zone of decreased stress (Aurelio et al., 2021c).

    However, when Coulomb stress transfer modeling considers an optimally-oriented receiver fault — assumed to be aligned with the stress field, thus promoting failure — all five earthquakes that succeeded the July 24 magnitude-6.6 earthquake fall within the lobe of increased stress at 65 miles (104 kilometers) depth (Fig. 2). The hypocenters — the locations on the fault where each earthquake nucleated — cluster within the calculated region of increased stress, which suggests triggering of all five quakes by the magnitude-6.6 July 24 event.

    2
    Figure 2. Seismotectonics of six moderate magnitude, thrust-mechanism earthquakes (shown by beachballs) occurring in the same region in Batangas, southern Luzon, Philippines, within a period of five months (July 24 to December 13, 2021). Result of Coulomb stress change modeling shown. July 24 magnitude-6.6 as source, with optimally-oriented fault as receiver. References: Jarvis et al., 2008 for SRTM topography; Weatherall et al., 2020 for bathymetry; Toda et al., 2011 for Coulomb stress transfer modeling; PHIVOLCS for earthquake data. GMT (Wessel and Smith, 1995) was used to generate the map. See text for more discussion. Credit: Aurelio, Catugas, Escudero, Lagmay,Tapang.

    Cause for concern?

    Based on the data collected during the last decade (Aurelio et al., 2021b), an average of 2.5 events larger than magnitude-5.0 strike per year within 50 kilometers of the July 24 magnitude-6.6 event. The recent spate of moderate quakes — each separated by less than a month — far exceeds this average and suggests that this is an evolving sequence.

    Could these six moderate magnitude earthquakes occurring over a short period of time indicate that stresses are being released rapidly? Or could these be lower-magnitude foreshocks of a larger event that has yet to strike? The latter is a possibility and should serve as a reminder to the 25 million inhabitants of Metro Manila and surrounding provinces that this region is vulnerable to a large earthquake. Preparedness and readiness are vital.

    Low-cost seismology studies

    The December 13 tremor was recorded by low-cost seismometers partly belonging to Public Seismic Network that is currently being established by the College of Science of the University of the Philippines-Diliman (UP Diliman) in Quezon City (Fig. 3). These low-cost seismometers, developed by Raspberry Shake, have been tried and tested both in the laboratory (Anthony et al., 2019) and in the field (Manconi et al., 2018; Winter et al., 2021; Holmgren, 2021).

    3
    Figure 3. Earthquake information generated by a Raspberry Shake station located nearest to the Public Seismic Network hub located inside the University of the Philippines-Diliman campus in Quezon City. The figure is a screenshot from the mobile phone app showing on the: upper panel – the date and time (local) of the seismic event, earthquake parameters (magnitude-5.5 and focal depth of 157 kilometers), station ID: R5160, map showing the locations of the Raspberry Shake seismic station and the epicenter and, station-to-epicenter distance in kilometers; middle panel – the waveform of the earthquake, clearly delineating the first P and S waves; lower panel – wave frequency distribution as a function of time. Credit: Aurelio, Catugas, Escudero, Lagmay, Tapang

    The earthquake parameters for December’s quake, generated by the UP Diliman-based network, include a calculated magnitude of 5.5, which compares well with magnitudes calculated by established international seismological observatories such as The Geological Survey (US) – National Earthquake Information Center (USGS-NEIC), GEOFON German Research Center for Geosciences (GEOFON-GFZ, Potsdam, Germany) and PHIVOLCS (Philippines). The low-cost, Raspberry Shake-derived earthquake depth of 98 miles (157 kilometers) is close to that computed by USGS-NEIC, but varies significantly from GEOFON-GFZ (69 miles/111 kilometers) and PHIVOLCS (64 miles/104 kilometers) estimates.

    Currently, most of these low-cost seismometers are owned and operated by ordinary citizens on their private properties. Though the stations are still scarce, there are good indications that more citizens are interested in setting up their own stations to join the UP Diliman-based network. Efforts are underway to find funds for more seismometers to deploy in schools throughout the country, with the aims of expanding the network and serving as a learning and teaching platform for students interested in earthquake studies.

    Meanwhile, at the UP National Institute of Physics (UP-NIP), a group of scientists from the institutes’ Instrumentation Physics Laboratory (ILP), is developing a low-cost seismic network consisting of accelerometers manufactured from commercially available components (Fig. 4). Each accelerometer costs less than $200 USD to manufacture. This network is part of a study to understand how shaking decays with distance from the source and how it is influenced by the nature of the ground underneath — called a ground attenuation relationship. Current attenuation relationships used in the country come from outside the Philippines, including experimental results from artificially induced, low-magnitude earthquakes, and data gathered directly from natural earthquakes.

    5
    Figure 4. Custom-made ground motion sensor (accelerometer) fabricated at the Instrumentation Physics Laboratory (IPL) of the University of the Philippines National Institute of Physics. The sensor contains the following components: (Left photo) (1) digital accelerometer; (2) development board containing the microcontroller, SD card module, and antenna for Long Range (LoRa) reception capabilities; (3) power section of board; (4) GPS module; (5) Real Time Clock (RTC) module; (6) antenna; (7) storage module; (8) power switch, (9) connection to the battery (not seen in picture) secured at the bottom of the container. (Right photo) Sensor assembled inside a closed, laser-cut acrylic sheet, with the electronic parts secured inside, connected to a pipe that serves as an extended antenna. The acrylic box is equipped with a level (button on top) to ensure horizontality of the base of the sensor. Credit: Aurelio (ongoing).

    These complementary efforts to establish low-cost seismological observatories serve two purposes. The Raspberry Shake network promotes citizen science. The second effort led by scientists helps Philippine researchers conduct innovative but inexpensive earthquake research. Both efforts hold promise in contributing to hazard resilience in an earthquake-prone country that often lacks scientific research funds.

    References

    Anthony, R.E., Ringler, A., Wilson D.C., and Wolin, E. (2019). Do Low-Cost Seismographs Perform Well Enough for Your Network? An Overview of Laboratory Tests and Field Observations of the OSOP Raspberry Shake 4D. Seismological Research Letters. 90 (1): 219-228.

    Aurelio, M. (ongoing). Project Leader: Establishing a ground attenuation relation for the Philippines using artificial blasting methods. Project funded by the University of the Philippines – Office of the Vice-President for Academic Affairs (UP-OVPAA) under the Enhanced Creative Work Research Grant (ECWRG).

    Aurelio, M., Lagmay, M., Escudero, J. A., and Catugas, S. (2021a). Latest Philippine earthquake reveals tectonic complexity, Temblor, doi.org/10.32858/temblor.191

    Aurelio, M., Lagmay, M., Escudero, J. A., and Catugas, S. (2021b). Philippine fault jolts Batangas again, with magnitude-5.8 quake, Temblor, doi.org/10.32858/temblor.198

    Aurelio, M., Lagmay, M., Escudero, J. A., and Catugas, S. (2021c). Magnitude-5.7 Batangas earthquake puzzles researchers, Temblor, doi.org/10.32858/temblor.21

    GEOFON German Research Center for Geosciences. Available at: http://www.geofon.gfz-potsdam.de

    Holmgren, J.M and Werner, M. (2021). Raspberry Shake Instruments Provide Initial Ground‐Motion Assessment of the Induced Seismicity at the United Downs Deep Geothermal Power Project in Cornwall, United Kingdom. The Seismic Record 1 (1): 27–34.

    Jarvis, A., H.I. Reuter, A. Nelson, E. Guevara (2008). Hole-filled SRTM for the globe Version 4, available from the CGIAR-CSI SRTM 90m Database (http://srtm.csi.cgiar.org).

    Manconi, A., Coviello, V. and Galletti, M. (2018). Short Communication: Monitoring Rockfall with the Raspberry Shake. Earth Surface Dynamics 6(4): 1219-1227.

    Observatoire GEOSCOPE. Available at: http://geoscope.ipgp.fr/index.php/en/

    Philippine Institute of Volcanology and Seismology (PHIVOLCS). Available at: http://www.phivolcs.dost.gov.ph

    Toda, Shinji, Stein, R.S., Sevilgen, Volkan, and Lin, J. (2011). Coulomb 3.3 Graphic-rich deformation and stress-change software for earthquake, tectonic, and volcano research and teaching—user guide: U.S. Geological Survey Open-File Report 2011–1060, 63 p., available at https://pubs.usgs.gov/of/2011/1060/

    United States Geological Survey – National Earthquake Information Center (USGS-NEIC). Available at: http://www.earthquake.usgs.gov

    Weatherall P., Tozer B., Arndt J.E., Bazhenova E., Bringensparr C., Castro C.F., Dorschel B., Ferrini V., Hehemann L., Jakobsson M., Johnson P., Ketter T., Mackay K., Martin T.V., Mayer L.A., McMichael-Phillips J., Mohammad R., Nitsche F.O., Sandwell D.T., Snaith H., Viquerat S. (2020). The GEBCO_2020 Grid – a continuous terrain model of the global oceans and land. British Oceanographic Data Centre, National Oceanography Centre, NERC, UK. doi:10.5285/a29c5465-b138-234d-e053-6c86abc040b9

    Wessel, P. and Smith, W.H.F., (1995). New version of the Generic Mapping Tools released. EOS Trans. Am. Geophys. Union 76, 329.

    Winter, K., Lombardi, D. Diaz-Moreno A., and Bainbridge, R. (2021). Monitoring Icequakes in East Antarctica with the Raspberry Shake. Seismological Research Letters. Doi: https://doi.org/10.1785/0220200483

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    _____________________________________________________________________________________

    Earthquake Alert

    1

    Earthquake Alert

    Earthquake Network project Earthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    3
    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

    QuakeAlertUSA

    1

    About Early Warning Labs, LLC

    Early Warning Labs, LLC (EWL) is an Earthquake Early Warning technology developer and integrator located in Santa Monica, CA. EWL is partnered with industry leading GIS provider ESRI, Inc. and is collaborating with the US Government and university partners.

    EWL is investing millions of dollars over the next 36 months to complete the final integration and delivery of Earthquake Early Warning to individual consumers, government entities, and commercial users.

    EWL’s mission is to improve, expand, and lower the costs of the existing earthquake early warning systems.

    EWL is developing a robust cloud server environment to handle low-cost mass distribution of these warnings. In addition, Early Warning Labs is researching and developing automated response standards and systems that allow public and private users to take pre-defined automated actions to protect lives and assets.

    EWL has an existing beta R&D test system installed at one of the largest studios in Southern California. The goal of this system is to stress test EWL’s hardware, software, and alert signals while improving latency and reliability.

    Earthquake Early Warning Introduction

    The United States Geological Survey (USGS), in collaboration with state agencies, university partners, and private industry, is developing an earthquake early warning system (EEW) for the West Coast of the United States called ShakeAlert. The USGS Earthquake Hazards Program aims to mitigate earthquake losses in the United States. Citizens, first responders, and engineers rely on the USGS for accurate and timely information about where earthquakes occur, the ground shaking intensity in different locations, and the likelihood is of future significant ground shaking.

    The ShakeAlert Earthquake Early Warning System recently entered its first phase of operations. The USGS working in partnership with the California Governor’s Office of Emergency Services (Cal OES) is now allowing for the testing of public alerting via apps, Wireless Emergency Alerts, and by other means throughout California.

    ShakeAlert partners in Oregon and Washington are working with the USGS to test public alerting in those states sometime in 2020.

    ShakeAlert has demonstrated the feasibility of earthquake early warning, from event detection to producing USGS issued ShakeAlerts ® and will continue to undergo testing and will improve over time. In particular, robust and reliable alert delivery pathways for automated actions are currently being developed and implemented by private industry partners for use in California, Oregon, and Washington.

    Earthquake Early Warning Background

    The objective of an earthquake early warning system is to rapidly detect the initiation of an earthquake, estimate the level of ground shaking intensity to be expected, and issue a warning before significant ground shaking starts. A network of seismic sensors detects the first energy to radiate from an earthquake, the P-wave energy, and the location and the magnitude of the earthquake is rapidly determined. Then, the anticipated ground shaking across the region to be affected is estimated. The system can provide warning before the S-wave arrives, which brings the strong shaking that usually causes most of the damage. Warnings will be distributed to local and state public emergency response officials, critical infrastructure, private businesses, and the public. EEW systems have been successfully implemented in Japan, Taiwan, Mexico, and other nations with varying degrees of sophistication and coverage.

    Earthquake early warning can provide enough time to:

    Instruct students and employees to take a protective action such as Drop, Cover, and Hold On
    Initiate mass notification procedures
    Open fire-house doors and notify local first responders
    Slow and stop trains and taxiing planes
    Install measures to prevent/limit additional cars from going on bridges, entering tunnels, and being on freeway overpasses before the shaking starts
    Move people away from dangerous machines or chemicals in work environments
    Shut down gas lines, water treatment plants, or nuclear reactors
    Automatically shut down and isolate industrial systems

    However, earthquake warning notifications must be transmitted without requiring human review and response action must be automated, as the total warning times are short depending on geographic distance and varying soil densities from the epicenter.

     
  • richardmitnick 10:21 pm on December 16, 2021 Permalink | Reply
    Tags: "Engaging communities with Canada’s earthquake early warning system", , , Canada is a vast country with diverse tectonic settings., , , Earthquake early warning systems can alert the public; emergency organizations; and critical infrastructure operators of impending shaking., , , Potential future seismicity in eastern Ontario and southern Quebec is more enigmatic-the St Lawrence Seaway passes through these regions and hosted several moderate to high magnitude earthquakes., temblor, The Cascadia Subduction Zone has generated a magnitude-9.0 earthquake roughly every 300-800 years according to NRCan.   

    From temblor : “Engaging communities with Canada’s earthquake early warning system” 

    1

    From temblor

    December 16, 2021

    By Meghomita Das, McGill University (CA)

    For residents of British Columbia, along the west coast of Canada, seeing a road sign that says, ‘Entering Tsunami Hazard Zone’ is a common occurrence.

    1
    A tsunami hazard warning sign in British Columbia informing people to move to higher areas in case of a strong earthquake. Credit: Ruth Hartnup, via Flickr, CC BY 2.0.

    The sign reminds travelers that British Columbia and much of western North America is earthquake country.

    Here, the Juan de Fuca tectonic plate is diving under the North American plate. This boundary, called the Cascadia Subduction Zone, extending from British Columbia down to northern California, has the potential to generate very large magnitude earthquakes and tsunamis and is currently primed for the next one.
    Cascadia subduction zone

    Ensuring Canadians are alerted of potentially harmful earthquakes in the region falls to Natural Resources Canada (NRCan), a federal organization tasked with developing policies and programs to utilize the country’s natural resources. Wednesday, at the American Geophysical Union Annual Meeting, a team of researchers at NRCan provided an update on Canada’s planned earthquake early warning system and discussed their efforts to engage the public.

    Earthquake early warning systems can alert the public; emergency organizations; and critical infrastructure operators of impending shaking. The additional seconds of advanced warning are enough for individuals to take appropriate actions and automated systems to protect sensitive equipment, thus reducing the devastating effects of earthquakes on lives and property. In large countries like Canada with two widely separated seismically active areas, implementing such a system is challenging but doable. NRCan is currently deploying such a system.

    Canadian seismicity

    Canada is a vast country with diverse tectonic settings. It has two major areas at moderate to high seismic risk: British Columbia and eastern Ontario-southern Quebec. Relevant to the former, the Cascadia Subduction Zone has generated a magnitude-9.0 earthquake roughly every 300-800 years according to NRCan.

    Potential future seismicity in eastern Ontario and southern Quebec is more enigmatic. Even though these areas do not lie on an active plate boundary, the St Lawrence Seaway, which passes through these regions, has hosted several moderate to high magnitude earthquakes over the last 40 years. Canada’s largest cities are in or close to these high-hazard areas.

    A network of sensors to detect quakes

    The Canadian earthquake early warning system will be implemented over the next three years. Three hundred land-based sensors will be deployed throughout British Columbia, Ontario, and Quebec to detect ground motions and quickly relay data, says Henry Seywerd, the project leader and a co-author of this study. In the future, NRCan plans to expand this network to northern and Atlantic Canada.

    The system will use the same software as the U.S. West Coast’s ShakeAlert early warning system [below] to ensure alert detection along the U.S.-Canada border. Alerts will be sent through the country’s National Public Alerting System. Additionally, facilities can be programed to open firehall and hospital emergency doors, halt trains and even back up important data servers when an alert is issued.

    “We want the people to understand that this system does not have predictive powers. It can only give us shaking alerts after an earthquake has been detected and encourage us to take the necessary actions,” says Alison Bird, the liaison and outreach officer at NRCan and a co-author of this study, who is handling the public engagement strategies for the project.

    Several workshops with critical infrastructure operators are planned to ensure that they are aware of the system’s benefits, Bird says. She will be working with Public Safety Canada, who operates the National Public Alerting System, along with provincial emergency management organizations to develop materials and activities to inform the public about the capabilities of this system, the need to take immediate actions like drop, cover and hold on and the steps to take to prepare for earthquakes at home, school and work.

    2
    Testing sensors that will be used for the earthquake early warning system’s network. The sensors measure strong ground motions. Credit: Natural Resources Canada and Nanometrics Inc., (shared by Alison Bird.)

    A system that works for the people

    Coastal First Nations communities of British Columbia have long documented historical earthquakes and their devastating effects as part of their oral traditions. These communities will be stakeholders in the implementation of the system and help NRCan to expand the network of stations on their lands, says Bird. Other partners include Emergency Management BC, The Great British Columbia ShakeOut (Grande Secousse) and Canadian Red Cross through the Inclusive Resilience project.

    Challenges encountered

    “Designing an earthquake early warning system is a complicated process. We want the main users to know that it is a warning system, but not a prediction system,” says Gabriel Lotto, ShakeAlert User Engagement Facilitator for the Pacific Northwest Seismic Network (PNSN), who was not associated with this study.

    One major challenge to deploying the system is increasing the awareness of earthquakes among the public and allowing them to interact with such an alerting system. This issue is echoed by Lotto for ShakeAlert. Since Eastern Canada generally experiences smaller magnitude earthquakes, residents may not be aware of their risk. One challenge the group at NRCan faces is ensuring those individuals know what to do if they receive an alert.

    Canada’s population is unevenly distributed near the east and west coasts and urban centers are located far from one another. The country, therefore, has large swaths where accessibility and communication are somewhat limited. The team plans to ensure the alerts are available across multiple platforms, like radio, television, internet and cellular networks, so that residents in these remote areas can get the alerts in time.

    Implementing the warning system

    Scientists are currently installing the seismic sensors, and the team hopes to announce the first official station very soon. Over the next couple of years, the system will be tested and fine-tuned before it is launched for the public. As the system is implemented, the team will continue their public engagement efforts and raise awareness about Canada’s seismic history and its new early warning system, Bird says.

    Further Reading

    Bird, A. L., Seywerd, H., Crane, S., Adams, J., & McCormack, D. A. (2021). Outreach and Engagement to ensure the success of an Earthquake Early Warning System in Canada. American Geophysical Union Fall Meeting 2021. https://agu.confex.com/agu/fm21/meetingapp.cgi/Paper/974633

    Natural Resources Canada. (2021). Earthquakes in Eastern Canada. https://www.earthquakescanada.nrcan.gc.ca/zones/eastcan-en.php

    Seywerd, H., McCormack, D. A., McKee, L., Bird, A. L., Nykolaishen, L., & Crane, S. (2021). Current status of the Canadian Earthquake Early Warning Program. American Geophysical Union Fall Meeting 2021. https://agu.confex.com/agu/fm21/meetingapp.cgi/Paper/950545

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    _____________________________________________________________________________________

    Earthquake Alert

    1

    Earthquake Alert

    Earthquake Network project Earthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    3
    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

    QuakeAlertUSA

    1

    About Early Warning Labs, LLC

    Early Warning Labs, LLC (EWL) is an Earthquake Early Warning technology developer and integrator located in Santa Monica, CA. EWL is partnered with industry leading GIS provider ESRI, Inc. and is collaborating with the US Government and university partners.

    EWL is investing millions of dollars over the next 36 months to complete the final integration and delivery of Earthquake Early Warning to individual consumers, government entities, and commercial users.

    EWL’s mission is to improve, expand, and lower the costs of the existing earthquake early warning systems.

    EWL is developing a robust cloud server environment to handle low-cost mass distribution of these warnings. In addition, Early Warning Labs is researching and developing automated response standards and systems that allow public and private users to take pre-defined automated actions to protect lives and assets.

    EWL has an existing beta R&D test system installed at one of the largest studios in Southern California. The goal of this system is to stress test EWL’s hardware, software, and alert signals while improving latency and reliability.

    Earthquake Early Warning Introduction

    The United States Geological Survey (USGS), in collaboration with state agencies, university partners, and private industry, is developing an earthquake early warning system (EEW) for the West Coast of the United States called ShakeAlert. The USGS Earthquake Hazards Program aims to mitigate earthquake losses in the United States. Citizens, first responders, and engineers rely on the USGS for accurate and timely information about where earthquakes occur, the ground shaking intensity in different locations, and the likelihood is of future significant ground shaking.

    The ShakeAlert Earthquake Early Warning System recently entered its first phase of operations. The USGS working in partnership with the California Governor’s Office of Emergency Services (Cal OES) is now allowing for the testing of public alerting via apps, Wireless Emergency Alerts, and by other means throughout California.

    ShakeAlert partners in Oregon and Washington are working with the USGS to test public alerting in those states sometime in 2020.

    ShakeAlert has demonstrated the feasibility of earthquake early warning, from event detection to producing USGS issued ShakeAlerts ® and will continue to undergo testing and will improve over time. In particular, robust and reliable alert delivery pathways for automated actions are currently being developed and implemented by private industry partners for use in California, Oregon, and Washington.

    Earthquake Early Warning Background

    The objective of an earthquake early warning system is to rapidly detect the initiation of an earthquake, estimate the level of ground shaking intensity to be expected, and issue a warning before significant ground shaking starts. A network of seismic sensors detects the first energy to radiate from an earthquake, the P-wave energy, and the location and the magnitude of the earthquake is rapidly determined. Then, the anticipated ground shaking across the region to be affected is estimated. The system can provide warning before the S-wave arrives, which brings the strong shaking that usually causes most of the damage. Warnings will be distributed to local and state public emergency response officials, critical infrastructure, private businesses, and the public. EEW systems have been successfully implemented in Japan, Taiwan, Mexico, and other nations with varying degrees of sophistication and coverage.

    Earthquake early warning can provide enough time to:

    Instruct students and employees to take a protective action such as Drop, Cover, and Hold On
    Initiate mass notification procedures
    Open fire-house doors and notify local first responders
    Slow and stop trains and taxiing planes
    Install measures to prevent/limit additional cars from going on bridges, entering tunnels, and being on freeway overpasses before the shaking starts
    Move people away from dangerous machines or chemicals in work environments
    Shut down gas lines, water treatment plants, or nuclear reactors
    Automatically shut down and isolate industrial systems

    However, earthquake warning notifications must be transmitted without requiring human review and response action must be automated, as the total warning times are short depending on geographic distance and varying soil densities from the epicenter.

     
  • richardmitnick 8:49 pm on November 10, 2021 Permalink | Reply
    Tags: "Newly identified fault in Seal Beach. CA. quietly rattles beneath the city", , , , , temblor   

    From temblor : “Newly identified fault in Seal Beach. CA. quietly rattles beneath the city” 

    1

    From temblor

    November 8, 2021
    Dan Gish
    Steve Boljen

    The Los Angeles basin is home to countless faults that range from thousands of feet to hundreds of miles in length. These include normal faults, reverse faults, thrust faults and strike-slip faults. The Newport-Inglewood Fault Zone (NIFZ) — a series of faults that extends between Newport and Inglewood, California — is one of the major sources of seismicity in the area. Many experts believed this zone is associated with several notable earthquakes, particularly in the Long Beach-Seal Beach area, including the 1933 magnitude-6.4 Long Beach earthquake.

    Less widely known are the basin’s numerous near-surface faults, some of which were recently identified in the immediate Seal Beach area. Scientists at 3D Seismic Solutions, a seismic data consulting company, in partnership with researchers at The California Institute of Technology (US), recently discovered one particularly active fault in this area. The finding highlights the difficulty faced by emergency managers, city planners and engineers in knowing potential hazards when planning for future earthquakes.

    Identifying near-surface faults

    A high-density seismic survey of the subsurface was conducted in early 2017 over approximately 28 square miles (72 square kilometers) of Long Beach and Seal Beach. A total of 5,354 sensors continuously recorded ground movement in the area for eight weeks.

    At one point during this period, vibrator trucks were deployed to generate seismic waves within the survey area. These waves reflect off features below ground — such as faults — and are detected by the sensors at the surface. The energy these vibrator trucks put into the ground is benign and undetectable by humans at the surface, but akin to an MRI, the bouncing waves allow us to generate a three-dimensional image of the subsurface down to 14,000 feet below sea level.

    1
    Area covered by the 2017 high-density seismic hazard survey. Credit: 3D Seismic Solutions.

    The subsurface data revealed several faults that had not been previously identified. These shallow faults extend upward to within 300 feet (90 meters) of the surface, however human activity has obscured meaningful fault information higher up. Our observations in the area suggest that these faults have also deformed sediments near the surface relatively recently, indicating these areas, shown in red on the map below, may be subject to continued deformation. Although it is impossible to predict when or how likely these faults are to move in the future, these data suggest they are active.

    3
    Location of the newly identified shallow faults (purple), areas of recent deformation (red) and the current surface trace of the NIFZ (yellow).

    Thousands of tiny earthquakes

    In addition to the bouncing seismic waves from the vibrating trucks, the sensors detected more than 3,000 micro-earthquakes during the eight-week period. Micro-seismic events are small earthquakes that are imperceptible by people, even those who are standing directly on the epicenter.

    Seismic sensors record these tiny events that occur along faults when they slip or creep. These micro-earthquakes do not pose a danger and can even help scientists locate otherwise hidden faults.

    Researchers at Caltech plotted the epicenters of the micro-seismic events onto our map and found that many of the events struck in a cluster along a section of the coast, close to one of our newly mapped faults. The micro-earthquakes occurred between tens of feet to more than one mile (several meters to two kilometers) below the surface, which is consistent with the inferred depth of this fault. The strong correlation between the events and the fault location indicates the fault was active during the eight-week period the sensors were deployed.

    If the events were related to human activities, such as construction or drilling, they would likely be dispersed throughout the urban area. Alternatively, if they were seismic noise related to waves crashing on the beach, we would expect them to be present along the entire shoreline. Yet, the linear cluster does not extend north of the San Gabriel River; it abruptly ends at a point where the newly mapped fault bends inland.

    4
    Correlation of Caltech’s micro-seismic events with 3D Seismic Solution’s fault map. Newly mapped faults in purple, Newport-Inglewood fault trace in red, and black dots represent the micro-seismic events, which occurred down to more than one mile (two kilometers) below the surface.

    Seismic hazard from unknown faults

    The Alquist-Priolo Act was created following the 1971 magnitude-6.6 San Fernando Valley earthquake, which cause widespread damage to structures when the Sierra Madre Fault slipped at the surface. The intent of the act was to reduce earthquake loses by regulating development near active surface faults. However, as demonstrated by the 1933 Long Beach earthquake, and more recently by the magnitude-6.7 Northridge earthquake, severe damage can occur even when a fault does not rupture all the way to the surface.

    Some of the major challenges in assessing seismic hazard include identifying subsurface faults and knowing how the fault will move. Faults that are not easily observed in a landscape, either because they do not reach the surface or evidence of offset has been paved over or otherwise removed, can be difficult to identify without detailed study of the subsurface. Such faults can still pose a hazard and do occasionally slip in a major earthquake, surprising seismologists. The damaging Northridge earthquake itself occurred on a previously unknown thrust fault, highlighting the hazard hidden faults pose in the region.

    Understanding the complex structure of the subsurface and the location of the many faults is critical in assessing potential earthquake risks. Presently in the Seal Beach area, the only identified Alquist-Priolo zone is along the Newport-Inglewood fault. The seismic data shows there are additional near-surface faults, some of which are currently active. High-density seismic surveys give scientists, city planners and emergency managers a better understanding of the hazards present in the Los Angeles basin. Emergency planners are keenly interested in the location of faults that cross planned evacuation routes, as well as first responder and key infrastructure locations.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    _____________________________________________________________________________________

    Earthquake Alert

    1

    Earthquake Alert

    Earthquake Network project Earthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    3
    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

    QuakeAlertUSA

    1

    About Early Warning Labs, LLC

    Early Warning Labs, LLC (EWL) is an Earthquake Early Warning technology developer and integrator located in Santa Monica, CA. EWL is partnered with industry leading GIS provider ESRI, Inc. and is collaborating with the US Government and university partners.

    EWL is investing millions of dollars over the next 36 months to complete the final integration and delivery of Earthquake Early Warning to individual consumers, government entities, and commercial users.

    EWL’s mission is to improve, expand, and lower the costs of the existing earthquake early warning systems.

    EWL is developing a robust cloud server environment to handle low-cost mass distribution of these warnings. In addition, Early Warning Labs is researching and developing automated response standards and systems that allow public and private users to take pre-defined automated actions to protect lives and assets.

    EWL has an existing beta R&D test system installed at one of the largest studios in Southern California. The goal of this system is to stress test EWL’s hardware, software, and alert signals while improving latency and reliability.

    Earthquake Early Warning Introduction

    The United States Geological Survey (USGS), in collaboration with state agencies, university partners, and private industry, is developing an earthquake early warning system (EEW) for the West Coast of the United States called ShakeAlert. The USGS Earthquake Hazards Program aims to mitigate earthquake losses in the United States. Citizens, first responders, and engineers rely on the USGS for accurate and timely information about where earthquakes occur, the ground shaking intensity in different locations, and the likelihood is of future significant ground shaking.

    The ShakeAlert Earthquake Early Warning System recently entered its first phase of operations. The USGS working in partnership with the California Governor’s Office of Emergency Services (Cal OES) is now allowing for the testing of public alerting via apps, Wireless Emergency Alerts, and by other means throughout California.

    ShakeAlert partners in Oregon and Washington are working with the USGS to test public alerting in those states sometime in 2020.

    ShakeAlert has demonstrated the feasibility of earthquake early warning, from event detection to producing USGS issued ShakeAlerts ® and will continue to undergo testing and will improve over time. In particular, robust and reliable alert delivery pathways for automated actions are currently being developed and implemented by private industry partners for use in California, Oregon, and Washington.

    Earthquake Early Warning Background

    The objective of an earthquake early warning system is to rapidly detect the initiation of an earthquake, estimate the level of ground shaking intensity to be expected, and issue a warning before significant ground shaking starts. A network of seismic sensors detects the first energy to radiate from an earthquake, the P-wave energy, and the location and the magnitude of the earthquake is rapidly determined. Then, the anticipated ground shaking across the region to be affected is estimated. The system can provide warning before the S-wave arrives, which brings the strong shaking that usually causes most of the damage. Warnings will be distributed to local and state public emergency response officials, critical infrastructure, private businesses, and the public. EEW systems have been successfully implemented in Japan, Taiwan, Mexico, and other nations with varying degrees of sophistication and coverage.

    Earthquake early warning can provide enough time to:

    Instruct students and employees to take a protective action such as Drop, Cover, and Hold On
    Initiate mass notification procedures
    Open fire-house doors and notify local first responders
    Slow and stop trains and taxiing planes
    Install measures to prevent/limit additional cars from going on bridges, entering tunnels, and being on freeway overpasses before the shaking starts
    Move people away from dangerous machines or chemicals in work environments
    Shut down gas lines, water treatment plants, or nuclear reactors
    Automatically shut down and isolate industrial systems

    However, earthquake warning notifications must be transmitted without requiring human review and response action must be automated, as the total warning times are short depending on geographic distance and varying soil densities from the epicenter.

     
  • richardmitnick 7:42 pm on September 15, 2021 Permalink | Reply
    Tags: "Faults connect beneath Salt Lake City-may increase hazard", As a city bounded by mountain ranges to the east and west Salt Lake City lies above a segment of the Wasatch Fault Zone and is underlain by unconsolidated sediment ., In March of 2020 a moderate magnitude-5.7 earthquake struck near Magna Utah jolting the population that lives across much of the Wasatch Front — the western side of the Wasatch Mountains., Secondary faults that branch off the main faults have the potential to slip during a large earthquake and could cause significant damages downtown., temblor, The faults of particular concern-Warm Springs and East Bench faults appear to connect underground directly beneath downtown Salt Lake City., There are active faults that seem to lie within a broad distributed zone throughout downtown., What the study seems to be showing is that earthquake energy does not stop between these two faults.   

    From temblor : “Faults connect beneath Salt Lake City-may increase hazard” 

    1

    From temblor

    September 14, 2021
    Kaelie Contreras, The Pennsylvania State University (US), Temblor Earthquake News Extern.

    In March of 2020 a moderate magnitude-5.7 earthquake struck near Magna Utah jolting the population that lives across much of the Wasatch Front — the western side of the Wasatch Mountains. After the earthquake, scientists observed several earthquake-induced phenomena concentrated in regions of water-rich, unconsolidated sediment. For example, liquefaction — when water-saturated soil loses its strength and acts as quick sand — occurred mostly near the shores of the Great Salt Lake. Sand boils, which occur when underground water pressure increases and pushes sand up to the surface, appeared as a result of liquefaction. Older unreinforced masonry buildings — those built of bricks or concrete blocks — suffered severe damage on the order of $100 million USD.

    As a city bounded by mountain ranges to the east and west Salt Lake City lies above a segment of the Wasatch Fault Zone and is underlain by unconsolidated sediment exposing it to these earthquake-related hazards. According to a recently published study in The Seismic Record, two individual faults of the Salt Lake City segment (the Warm Springs fault and East Bench fault) are connected to one another directly under downtown Salt Lake City, further increasing its susceptibility to earthquake damage.

    1
    Cobbles settled into wet clay shows minor liquefaction just a day after the 2020 Magna earthquake. Credit: Emily Kleber, Utah Geological Survey via UGS GeoData Archive.

    X-ray underneath the downtown corridor

    Before the Magna earthquake, lead author Lee Liberty, a research professor at Boise State University (US), wondered whether distant faults or those beneath downtown Salt Lake City caused sand boils, liquefaction, and other evidence of past soft sediment deformation found throughout the region.

    To answer this question, Lee and a team of scientists used an active source approach, which is like taking an x-ray of the earth’s structure. The “active source” part of this approach involved Lee and his team, along with the help of off-duty police officers, tapping the ground with a 440-pound (200-kilogram) weight to create mini-shakes that sent seismic waves into the shallow subsurface. Behind a vehicle, they dragged a fire hose containing ground sensors that detected the seismic waves that bounced back to the surface, off geologic structures in the ground beneath downtown Salt Lake City.

    2
    Seismic land streamer data collection in downtown Salt Lake City, 2017. Credit: Rich Giraud, Utah Geological Survey via UGS GeoData Archive.

    “There are active faults that seem to lie within a broad distributed zone throughout downtown,” says Lee. The team’s findings indicate that “there is potential for ground displacements beneath the downtown corridor where high-rise buildings either have been or will be constructed in the future,” he says. The faults of particular concern, the aforementioned Warm Springs and East Bench faults, appear to connect underground directly beneath downtown Salt Lake City, suggesting that if the Warm Springs fault moves it could activate the East Bench fault, and vice versa.

    What the study seems to be showing, says Emily Kleber, a geoscientist with the Geologic Hazards Program at the Utah Geological Survey, is that “earthquake energy does not stop between these two faults.” In other words, downtown Salt Lake City appears to sit above faults that could breach the surface, should energy from an earthquake activate either of them.

    New answers, more questions

    In terms of hazard to both existing and new buildings, Ivan Wong, a senior principal seismologist for Lettis Consultants International says that although Lee’s study indicates a zone of deformation between the two faults, the behavior of secondary faults that may accompany the main faults in the downtown area is unknown. These secondary faults that branch off the main faults have the potential to slip during a large earthquake, and if they reach the surface, says Wong, they could cause significant damages downtown.

    “It’s such an important issue for engineering, and also to know what we’re up against,” explains Kleber, “to model what could happen if we do have a big earthquake.”

    In the future, Lee hopes to revisit downtown Salt Lake to acquire additional seismic data from more closely spaced profiles to understand the interaction between the two faults at a higher resolution, determine how far the fault zones extend, and estimate how fast individual faults — both primary and secondary — move. This clearer picture of what’s happening in the subsurface would help scientists to better forecast when and where future earthquakes may occur and determine the potential for disaster.

    References:

    Liberty, L. M., St. Clair, J., & McKean, A. P. (2021). A Broad, Distributed Active Fault Zone Lies beneath Salt Lake City, Utah. The Seismic Record, 1(1), 35-45.

    Kleber, E. J., McKean, A. P., Hiscock, A. I., Hylland, M. D., Hardwick, C. L., McDonald, G. N., … & Erickson, B. A. (2021). Geologic Setting, Ground Effects, and Proposed Structural Model for the 18 March 2020 M w 5.7 Magna, Utah, Earthquake. Seismological Society of America, 92(2A), 710-724.

    Wasatch Front Unreinforced Masonry Risk Reduction Strategy (2021). FEMA.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    _____________________________________________________________________________________

    Earthquake Alert

    1

    Earthquake Alert

    Earthquake Network project Earthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    3
    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

    QuakeAlertUSA

    1

    About Early Warning Labs, LLC

    Early Warning Labs, LLC (EWL) is an Earthquake Early Warning technology developer and integrator located in Santa Monica, CA. EWL is partnered with industry leading GIS provider ESRI, Inc. and is collaborating with the US Government and university partners.

    EWL is investing millions of dollars over the next 36 months to complete the final integration and delivery of Earthquake Early Warning to individual consumers, government entities, and commercial users.

    EWL’s mission is to improve, expand, and lower the costs of the existing earthquake early warning systems.

    EWL is developing a robust cloud server environment to handle low-cost mass distribution of these warnings. In addition, Early Warning Labs is researching and developing automated response standards and systems that allow public and private users to take pre-defined automated actions to protect lives and assets.

    EWL has an existing beta R&D test system installed at one of the largest studios in Southern California. The goal of this system is to stress test EWL’s hardware, software, and alert signals while improving latency and reliability.

    Earthquake Early Warning Introduction

    The United States Geological Survey (USGS), in collaboration with state agencies, university partners, and private industry, is developing an earthquake early warning system (EEW) for the West Coast of the United States called ShakeAlert. The USGS Earthquake Hazards Program aims to mitigate earthquake losses in the United States. Citizens, first responders, and engineers rely on the USGS for accurate and timely information about where earthquakes occur, the ground shaking intensity in different locations, and the likelihood is of future significant ground shaking.

    The ShakeAlert Earthquake Early Warning System recently entered its first phase of operations. The USGS working in partnership with the California Governor’s Office of Emergency Services (Cal OES) is now allowing for the testing of public alerting via apps, Wireless Emergency Alerts, and by other means throughout California.

    ShakeAlert partners in Oregon and Washington are working with the USGS to test public alerting in those states sometime in 2020.

    ShakeAlert has demonstrated the feasibility of earthquake early warning, from event detection to producing USGS issued ShakeAlerts ® and will continue to undergo testing and will improve over time. In particular, robust and reliable alert delivery pathways for automated actions are currently being developed and implemented by private industry partners for use in California, Oregon, and Washington.

    Earthquake Early Warning Background

    The objective of an earthquake early warning system is to rapidly detect the initiation of an earthquake, estimate the level of ground shaking intensity to be expected, and issue a warning before significant ground shaking starts. A network of seismic sensors detects the first energy to radiate from an earthquake, the P-wave energy, and the location and the magnitude of the earthquake is rapidly determined. Then, the anticipated ground shaking across the region to be affected is estimated. The system can provide warning before the S-wave arrives, which brings the strong shaking that usually causes most of the damage. Warnings will be distributed to local and state public emergency response officials, critical infrastructure, private businesses, and the public. EEW systems have been successfully implemented in Japan, Taiwan, Mexico, and other nations with varying degrees of sophistication and coverage.

    Earthquake early warning can provide enough time to:

    Instruct students and employees to take a protective action such as Drop, Cover, and Hold On
    Initiate mass notification procedures
    Open fire-house doors and notify local first responders
    Slow and stop trains and taxiing planes
    Install measures to prevent/limit additional cars from going on bridges, entering tunnels, and being on freeway overpasses before the shaking starts
    Move people away from dangerous machines or chemicals in work environments
    Shut down gas lines, water treatment plants, or nuclear reactors
    Automatically shut down and isolate industrial systems

    However, earthquake warning notifications must be transmitted without requiring human review and response action must be automated, as the total warning times are short depending on geographic distance and varying soil densities from the epicenter.

     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel
%d bloggers like this: