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  • 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.

     
  • richardmitnick 11:28 am on September 4, 2021 Permalink | Reply
    Tags: "Can smartphones affixed to buildings detect earthquakes?", Accelerometers provide between 10 and 30 seconds of warning before the earthquake’s waves arrive., , , , , Smartphones come packaged with GPS location services-constant communication via cell networks-and a device called an accelerometer., Smartphones have all the three components that are there in a scientific grade seismic station., temblor, The accelerometer can record any shaking your phone may experience.   

    From temblor : “Can smartphones affixed to buildings detect earthquakes?” 

    1

    From temblor

    September 1, 2021
    By Meghomita Das, Department of Earth & Planetary Sciences, McGill University (CA).

    Damaging earthquakes can strike at any time, leaving behind a trail of devastation. Recovery from such events can take several years. Unfortunately, scientists cannot forecast the exact time an earthquake will strike. But extensive research in the field of earthquake early warning systems is ongoing. Such systems can provide seconds of warning, which could save lives and prevent people from overwhelming emergency management systems.

    1
    The 2009 Cinchona earthquake, that struck close to the capital city of San Jose, caused 34 fatalities and collapsed houses across Costa Rica. Credit: Capt Diana Parzik, US Army, via Wikipedia, CC-Public Domain Mark 1.0.

    Earthquake early warning systems work by having a densely distributed network of seismic stations capable of rapidly detecting an earthquake, and by sending alerts that warn of shaking to the population. A significant hurdle to designing and implementing such systems is the high cost of installing multiple, scientific-grade seismic stations across earthquake-prone regions. For countries like India or Mexico, which have limited resources and high population densities, these expensive networks are not feasible.

    In a recent study published in AGU Advances, a team of scientists explored whether a low-cost, robust and operational earthquake early warning system — built around comparatively cheap smartphones instead of seismic stations — might become a reality in the near future in Costa Rica, a country that regularly experiences high-magnitude earthquakes. During a six-month testing period, this network, called Alerta Sismica Temprana Utilizando Telefonos Inteligentes (ASTUTI), a collaborative effort between The Geological Survey (US) and the National University of Costa Rica [Universidad Nacional de Costa Rica] (CR), detected and sent alerts for five earthquakes that produced significant shaking in San Jose, Costa Rica’s densely populated capital city.

    Smartphones and earthquakes

    Smartphones come packaged with GPS location services-constant communication via cell networks-and a device called an accelerometer that helps your phone’s screen rotate as you move it around. The accelerometer can also record any shaking your phone may experience. “Essentially, your phone costs maybe $100 and has all the three components that are there in a scientific grade seismic station, which costs thousands of dollars,” says Marino Protti, a study co-author and a seismologist at the Observatorio Vulcanologico y Sismologico de Costa Rica (Universidad Nacional).

    To set up the ASTUTI network, the team deployed 82 Android smartphones, encased in protective boxes, throughout Costa Rica, at an annual cost of $20,000 USD. They installed these smartphones inside buildings, on either the walls or floors of the ground story. The phones are plugged in to AC power supplies.

    The accelerometers stream data via cellular networks in real time to the cloud, says Protti. A cloud-based server receives signals from all stations. So, when an earthquake strikes and four sites detect strong ground motion, an alert goes out to people in San Jose, providing between 10 and 30 seconds of warning before the earthquake’s waves arrive, he explains.

    San Jose’s location relative to the Middle America Trench — where the Cocos Plate dives beneath the Caribbean Plate — is perfect to test the efficacy of this network because the city is in the Goldilocks position. It’s far enough from the trench such that issuing a timely alert is feasible, but close enough such that the population will feel shaking. The ASTUTI network also issued alerts as soon as events were detected, rather than either waiting for an earthquake to grow larger or trying to define its characteristics. This choice gave people more time to protect themselves.

    Did ASTUTI feel it?

    During its six months of operation, a group of people selected to receive alerts via phone were notified of five events that ASTUTI detected, with magnitudes ranging between 4.8 and 5.3. Thirteen earthquakes struck Costa Rica in that time, but the other eight earthquakes did not produce significant shaking to warrant an alert. For two of the five detected events, ASTUTI sent out alerts at the earliest possible time — when the first wave from the earthquake, also called the P-wave — was detected by smartphones. This provided people with enough time to take protective action. Moreover, each of the five detected events were accompanied by a “Did You Feel It” report by the U.S. Geological Survey. This citizen science project collects “felt reports” from people who felt shaking (or didn’t) during earthquakes worldwide. In other words, the earthquakes that shook people enough to file a report were detected by the ASTUTI network.

    3
    One of the ASTUTI earthquake early warning stations. Image on the left shows the encased smartphone, and image on the right shows the software interface that records data from the station. Credit: Brooks et al., 2021, CC-BY-NC-ND 4.0.

    With recent advancements in earthquake early warning, there is a potential for developing a network consisting of expensive high-end devices complemented by a larger number of low-cost devices capable of detecting ground motion, says Raj Prasanna, a telecommunications and electronics engineer and senior lecturer at Massey University-New Zealand [Te Kunenga Ki Pūrehuroa](NZ) who was not involved with this study. “Together, they can become an affordable warning network, with acceptable levels of reliability,” he says.

    In the next phase of development, the team plans to create a hybrid system by integrating this smartphone-enabled network with Costa Rica’s existing scientific-grade seismic network, which will improve the accuracy and reduce time of detection of the earthquake early warning system.

    What the public wants

    Setting up an earthquake early warning system that effectively prompts the public to get to safety is challenging, says Sarah Minson of the USGS, a co-author of the new study. “How do we find out what people want; how do we find out if they are enjoying the system?” she asks. Because earthquake early warning systems are relatively new and people haven’t interacted with them, Minson says, they may not have a personal feel for what works for them. Plus, every country’s needs are different. People’s responses to the same alerts vary depending upon how that specific society culturally reacts to natural hazards.

    To that end, the team plans to develop a smartphone-based application. In the future, they will work with the National Commission for Risk Prevention and Emergency Management in Costa Rica to measure how the Costa Rican population perceives earthquake early warning. The goal, says Protti, is to create a more coordinated response plan for earthquakes in Costa Rica. By coupling effective messaging with earthquake early warning, the public will have crucial seconds to take actions that can protect their lives.

    References

    Brooks, B. A., Protti, M., Ericksen, T., Bunn, J., Vega, F., Cochran, E. S., … & Glennie, C. L. (2021). Robust earthquake early warning at a fraction of the cost: ASTUTI Costa Rica. AGU Advances, 2(3), e2021AV000407.

    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 3:47 pm on August 27, 2021 Permalink | Reply
    Tags: , , , , , Scientists surveying the seabed off New Zealand’s east coast have uncovered undersea mountains that help explain mysterious slow-motion earthquakes., So why do some faults slip suddenly and set off deadly earthquakes while others slide slowly and stealthily?, temblor, The Hikurangi Margin zone poses a significant earthquake and tsunami hazard to coastal communities in New Zealand but the largest earthquakes only seem to occur toward the south of the margin., The team used electromagnetic methods to essentially take an MRI scan of the seabed along the Hikurangi Margin where the Pacific Plate dives beneath the Australian Plate., This study is the first to use electromagnetic methods to map out water trapped in rocks beneath the seafloor offshore.   

    From temblor : “Submarine mountains can subdue earthquakes” 

    1

    From temblor

    August 23, 2021

    Scientists surveying the seabed off New Zealand’s east coast have uncovered undersea mountains that help explain mysterious slow-motion earthquakes.

    By Erin Martin-Jones, Ph.D., Department of Earth Sciences, University of Cambridge (UK)

    Earth’s tectonic plates are constantly jostling for space — colliding and diving under one another in a dance that sculpts dramatic mountain chains, fuels volcanic eruptions and delivers earth-shattering tremors. But sometimes these forces can have more subtle impacts. Take, for instance, silent earthquakes or “slow-slip events,” which can move at slow-motion speeds, stretching their ruptures over weeks to months. Often, no one feels a thing, and these events go undetected even by seismometers.

    So why do some faults slip suddenly and set off deadly earthquakes while others slide slowly and stealthily? A new study [Nature] suggests that off the coast of New Zealand, where thousands of small quakes occur each year, excess water locked within undersea mountains, or “seamounts,” can promote the silent sliding linked to slow-motion earthquakes.

    2
    Map of Hikurangi Subduction Zone, showing locations where electromagnetic receivers were deployed to collect data. Credit: Christine Chesley, using GeoMapApp and data from William Ryan et al., Geochemistry, Geophysics, Geosystems (2009).

    The Hikurangi Margin Subduction Zone

    To understand slow-slip earthquakes off New Zealand’s eastern coast, a team of researchers led by Christine Chesley of Columbia University’s Lamont-Doherty Earth Observatory first had to figure out a way to peer into the depths of a subduction zone.

    The team used electromagnetic methods to essentially take an MRI scan of the seabed along the Hikurangi Margin where the Pacific Plate dives beneath the Australian Plate. That subduction motion along the margin is partly responsible for the more than 15,000 earthquakes in the region each year. Most are so small that they go unnoticed, but between 150 and 200 are large enough to be felt.

    3
    The research vessel hauls in one of the receivers used to take electromagnetic measurements of the seabed. Credit: Kerry Key.

    This subduction zone poses a significant earthquake and tsunami hazard to coastal communities in New Zealand, but the largest earthquakes only seem to occur toward the south of the margin — and scientists want to know why. “One of the fascinating things about this area, and why so many have studied it, is the puzzling variation in earthquake hazards over a very small area,” Chesley says.

    Although large earthquakes haven’t struck the North Island in roughly the last 200 years, evidence of ancient quakes is written in the rocks along the coastline, which have been jolted upward by past seismic events.

    Diving beneath the hidden depths of silent earthquakes

    In December 2018, the research team began a month-long deep-sea cruise, collecting profiles of the seafloor in the northern part of the subduction zone margin, which is studded with large seamounts. “Although other studies have suggested that seamounts may contribute to small, rather than large and destructive earthquakes, it’s been unclear exactly how those mountains interact with the seafloor as they are subducted,” says Chesley.

    Chesley’s eye was drawn to two seamounts: the Tūranganui Knoll, located about 110 kilometers southeast of the east coast city of Gisborne, and an unnamed one that is closer to the margin and is currently being subducted. A cluster of tiny earthquakes related to a 2014 slow-slip event occurred around the second seamount, which first began subducting about a million years ago.

    5
    Christine Chesley and Eric Attias operate the Scripps Undersea Electromagnetic Source Instrument (SUESI) during a deep-tow. SUESI is attached to the ship via a coaxial cable and must be “flown” about 100 meters above the seafloor. Credit: Kerry Key.

    Peeling back the layers of a seamount

    Chesley’s team’s electric conductivity survey revealed that each seamount was made up of layers of varying porosity, which held water and conducted electricity differently. Each had a solid core surrounded by a layer of loose, cindery material that acts a bit like a sponge. In fact, the team found that seamounts lock away three to five times more water than typical oceanic crust. This water can act as a lubricant to help tectonic plates glide into Earth’s interior without setting off a large earthquake.

    “It makes a lot of sense, knowing how they form, but we really weren’t expecting them to be such heterogeneous masses of rock,” says Chesley. She noted that the nuance in material can really affect how the subducting plate moves and expels water when it is subducted.

    Because both seamounts had a similar structure, the researchers think that even actively subducting seamounts retain their structural strength — so much so that they can damage the overriding plate, causing tiny faults that dissipate the energy and result in slow-slip events.

    New methods

    This study is the first to use electromagnetic methods to map out water trapped in rocks beneath the seafloor offshore, says Susan Ellis, a geophysicist at GNS Science, who was not involved in the study. “Mapping the structure of the seafloor is extremely challenging and has only recently become viable. This research is at the cutting edge of new geophysical imaging methods,” Ellis says.

    3
    Electromagnetic receivers can be seen on the back deck of the R/V Roger Revelle during particularly rough seas. Credit: Kerry Key.

    “These results are very exciting … they show just how subducting topography can impact water content,” she adds. That, in turn, reveals the type of slipping. “Understanding why slow-slip events occur is critical for estimating New Zealand’s earthquake and tsunami hazard.”

    Factoring underwater oddities into hazard models

    “Seamounts are very common on the seafloor, but hazard models currently don’t consider how they contribute to slow-slip events,” says Chesley. “Now we know that we need to take seafloor topography into account — otherwise we’re not getting the full picture.”

    But Chesley and her team note that slow-slip earthquakes aren’t always subdued. In 1947, two unusual tsunamis were both associated with slow-slip behavior. And because they weren’t preceded by shaking, there was little warning.

    “Future work in other locations of the margin, and in other subduction zones with and without seamounts, will help us understand whether there are any other factors that also contribute to slow-slip events,” says Ellis. Or that contribute to a larger event, for that matter.

    References:

    Chesley, C., Naif, S., Key, K., & Bassett, D. (2021). Fluid-rich subducting topography generates anomalous forearc porosity. Nature, 595(7866), 255-260. doi.org/10.1038/s41586-021-03619-8

    Sun, T., Saffer, D. and Ellis, S., 2020. Mechanical and hydrological effects of seamount subduction on megathrust stress and slip. Nature Geoscience, 13(3), pp.249-255. doi.org/10.1038/s41561-020-0566-5

    Wallace, L.M., Webb, S.C., Ito, Y., Mochizuki, K., Hino, R., Henrys, S., Schwartz, S.Y. and Sheehan, A.F., 2016. Slow slip near the trench at the Hikurangi subduction zone, New Zealand. Science, 352(6286), pp.701-704. doi.org/10.1126/science.aaf2349

    Wang, K., & Bilek, S. L. (2011). Do subducting seamounts generate or stop large earthquakes? Geology, 39(9), 819-822. doi.org/10.1130/G31856.1

    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 12:40 pm on August 18, 2021 Permalink | Reply
    Tags: "Are the 2021 and 2010 Haiti earthquakes part of a progressive sequence?", , , , temblor   

    From temblor : “Are the 2021 and 2010 Haiti earthquakes part of a progressive sequence?” 

    1

    From temblor

    August 17, 2021
    By Ross Stein, Ph.D., Temblor, Inc., California (@rstein357)
    Shinji Toda, Ph.D., IRIDeS, Tohoku University [東北大学] (JP).
    Jian Lin, Ph.D. Southern University of Science and Technology [南方科技大學](CN), and Woods Hole Oceanographic Institution (US).
    Volkan Sevilgen, M.Sc., Temblor, Inc., California (@volkansevilgen)

    On Jan. 12, 2010, a magnitude-7.0 earthquake struck Léogâne, Haiti, just outside the capital of Port-au-Prince. The quake killed some 300,000 people, according to the Haitian government, and displaced hundreds of thousands more people. Though the quake was initially thought to have struck on the Enriquillo-Plantain Garden Fault, where the Caribbean Plate is separated from the Gonâve microplate, further investigation eventually indicated the quake occurred on a blind thrust fault now known as the Léogâne Fault. (Blind thrust faults are those that don’t reach Earth’s surface and result from compression.) On Aug. 14, 2021, a magnitude-7.2 quake struck along the same fault system, to the west of the epicenter of the 2010 quake. The death toll is already above 1,400 and thousands more are displaced. Those numbers are expected to rise, especially as a tropical storm barrels down on the island.

    Our analyses suggest that the disastrous 2010 earthquake likely brought the fault that ruptured in the Aug. 14, 2021 quake closer to failure. Some elements suggest a westward earthquake progression, but highly stressed sections of the fault system well to the east remain.

    Stress transferred by the 2010 quake to the site of the 2021 event

    Two weeks after the 2010 earthquake, we published a Coulomb stress analysis to gain insight as to what could happen next (Lin et al., 2010). We identified sections of the Enriquillo-Plantain Garden Fault (Mann et al., 2002) to the east and west of the 2010 rupture zone with significantly increased stress and hazard, as shown in Figure 1. The 2021 magnitude-7.2 Nippes, Haiti, earthquake struck on a patch that was brought 0.1 bar closer to failure. While 0.1 bar has been shown in many studies to be large enough to trigger earthquakes, it is nevertheless much smaller than the stress increases closer to both ends of the 2010 rupture, which we calculated to be 5-10 times larger. Symithe et al. (2013) obtained similar and more extensive results, providing independent confirmation of our calculations.

    1
    Figure 1. This is Figure 1 from Lin et al. (2010), annotated with the epicenter of the Aug. 14, 2021, magnitude-7.2 Nippes mainshock, which likely struck on a patch of the Enriquillo-Plantain Garden Fault System. Credit: Authors, after Lin et al. (2010).

    The fault map in Figure 1 might be oversimplified, as there are likely two adjacent faults running along the peninsula— the Enriquillo, as well as a blind thrust fault (Calais et al., 2010; Hayes et al, 2010; Prentice et al., 2010; Hashimoto et al., 2012; Douilly et al., 2013). Here, we refer to both faults as a fault system. But for both fault geometries, the 2010 earthquake stressed the site of the 2021 event.

    Why the 11-year wait for the next shoe to fall, and why the unruptured fault section between the two earthquakes (labeled “jump?” in Figure 2)? In our calculations, the impact of the stress change on seismicity fades with time, just as do the rate of aftershocks. So, while an immediate trigger is more likely, long delays are still possible. The jump or gap between the 2010 and 2021 ruptures could be explained by a strong fault patch that requires still more stress to rupture, it could mark a bend or break in the fault (Saint Fleur et al., 2020), or this section could have ruptured prehistorically, lowering the stress relative to adjacent patches. Irrespective of those speculations, we cannot rule out the possibility that the fault could soon rupture through that gap in a magnitude~6.5 aftershock.

    2
    Figure 2. Progressive westward rupture of the 2010 and 2021 earthquakes. It appears that there is a 15-kilometer-long jump or gap between them, one candidate among several for a future large earthquake. Credit: Temblor Inc.

    Stress transferred by the 2021 earthquake

    How has the fault stress been altered by the magnitude-7.2 event, which is about twice as large as its 2010 forerunner? In Figure 3, we calculate this in several different ways. Regardless of which approach we take, one can see that sections of the fault system to the east and west of the magnitude-7.2 rupture were brought significantly closer to failure. This is easiest to visualize in Figure 3a. But Figure 3b shows something else of importance: The faults that ruptured in the 2010 aftershocks have been re-stressed by the 2021 event, and so we could see a reawakening of the 2010 aftershock zone.

    3
    Figure 3. Stress transferred by the Aug. 14, 2021, magnitude-7.2 mainshock to surrounding faults. In (a), we calculate stress on faults with the same geometry as the mainshock, based on a preliminary finite fault model (USGS, 2021). Lobes of stress increase (red) extend in four directions. (b) Here we use the focal mechanisms of past earthquakes to infer the geometry of surrounding faults, which indicates that the faults that ruptured in 2010 aftershocks were re-stressed by the 2021 earthquake (red beachballs). (c) Because the density of focal mechanisms is very sparse, here we interpolate between focal mechanisms for a smooth grid. Credit: Temblor Inc.

    The 2021 earthquake had a predecessor in 1770

    Saint Fleur et al. (2020) excavated a trench along the Enriquillo–Plantain Garden fault near Clonard (shown in Figure 2), which turns out to be within the rupture of the 2021 mainshock. They found evidence for an earthquake in about 1770, with a range of uncertainty of 40 years, which they suggest corresponds to the June 3, 1770, magnitude~7.5 earthquake. The Enriquillo Fault has a long-term slip rate of about 9 millimeters/year at this location, so in the 250 years between the two events, about 2.0-2.5 meters of potential slip would have accumulated. According to the USGS (2021) finite fault model, the mean slip in the 2021 earthquake was about 1.5 meters, and so these inferences are roughly consistent: Stress released in the 1770 earthquake had rebuilt by about 2010, when a small amount of additional stress was transferred to the site, further ratcheting the fault toward failure.

    Earthquake forecast for the next 12 months

    We make a probabilistic forecast (Figure 4) of the next year by using the stress transferred from the 2010 and 2021 mainshocks, our smoothed grid of focal mechanisms (shown in Figure 3c), and the Global Earthquake Activity Rate (GEAR) model of Bird et al. (2015) (Figure 4b). The method we adopt (Toda and Stein, 2020) assumes that the impact of a large earthquake decays with time. The absence of a strong national seismic network limits our ability to test the forecast in Haiti, but the same approach has performed well in Japan, California and Chile.

    In the forecast (Figure 4a), we calculate an elevated hazard extending from Jeremie (population 122,000) near the west end of the peninsula, all the way to Port-au-Prince in the east, a surprisingly long extent of 200 kilometers. But in support of this calculation, Figure 2 shows numerous earthquakes both east of Port-au-Prince, and in the region around the Aug. 14, 2021, magnitude-7.2 rupture zone, more than the 11 years before the magnitude-7.2 event struck (the grey quakes). These quakes probably indicate that the hazard was high along this section of the Enriquillo-Plaintain Garden fault system since the 2010 magnitude-7.0 event struck.

    4
    Figure 4. Probabilistic forecast for 12-month periods. (a) This forecast considers the decaying impact of the stress transferred by the 2010 magnitude-7.0 and the 2021 magnitude-7.2 earthquakes on surrounding faults, following the approach of Toda and Stein (2020). Except for the 40 kilometers centered on the Aug. 14, 2021 rupture, a 220-kilometer-long section of the Enriquillo-Plantain Garden Fault System has a higher likelihood of hosting magnitude-5.0 or bigger quakes than during an average 12-month period, as shown in (b). Credit: Temblor Inc.

    Is the earthquake sequence headed west?

    One might be tempted to infer that the magnitude-7 earthquake sequence is progressing westward, in which case any future large shocks would strike less-populated areas along Haiti’s southern peninsula. The argument for this view is that the aftershocks of the 2010 and 2021 earthquakes are separated by about 15 kilometers, and in addition, the 2010 and 2021 events ruptured largely to the west, where most of their aftershocks lie.

    But our forecast tells a different story: The eastern sections of the fault are also calculated to have an elevated probability of large shocks, and unfortunately, these areas are more populated. One might ask if the 11 years since the 2010 quake without a large shock to the east means that we can exclude this possibility. But there have been about 10 shocks to the east of the 2010 rupture in the past decade (Figure 2), and so, in our judgment, a larger earthquake there remains a possibility.

    References

    Bird, P., D.D. Jackson, Y.Y. Kagan, C. Kreemer, and R.S. Stein (2015), GEAR1: A global earthquake activity rate model constructed from geodetic strain rates and smoothed seismicity, Bull. Seismol. Soc. Amer., 105, 2538–2554.

    Calais, E., A. Freed, G. Mattioli, F. Amelung, S. Jónsson, P. Jansma, S.-H. Hong, T. Dixon, C. Prépetit, and R. Momplaisir (2010), Transpressional rupture of an unmapped fault during the 2010 Haiti earthquake. Nature Geosci., 3, 794-799, doi:10.1038/ngeo992.

    Douilly, R., et al. (2013), Crustal structure and fault geometry of the 2010 Haiti earthquake from temporary seismometer deployments, Bull. Seismol. Soc. Am., 103, 2305–2325, doi: 10.1785/0120120303.

    Hashimoto, M., Y. Fukushima, and Y. Fukahata (2011), Fan-delta uplift and mountain subsidence during the Haiti 2010 earthquake, Nature Geosci., 4, 255–259, doi:10.1038/ngeo1115.

    Hayes, G. P., R. W. Briggs, A. Sladen, E. J. Fielding, C. Prentice, K. Hudnut, P. Mann, F. W. Taylor, A. J. Crone, R. Gold, T. Ito, and M. Simons (2010), Complex rupture during the 12 January 2010 Haiti earthquake, Nature Geosci., 3, 800–805, doi:10.1038/ngeo977.

    Lin, J., Stein, R. S., Sevilgen, V., and Toda, S. (2010), USGS-WHOI-DPRI Coulomb stress-transfer model for the January 12, 2010, MW=7.0 Haiti earthquake: U.S. Geological Survey Open-File Report 2010-1019, 7 p.

    Mann, P., E. Calais, J.-C. Ruegg, C. DeMets, P. E. Jansma, and G. S. Mattioli (2002), Oblique collision in the northeastern Caribbean from GPS measurements and geological observations, Tectonics, 21, 1057, doi:10.1029/2001TC001304.

    Prentice, C. S., P. Mann, A. J. Crone, R. D. Gold, K. W. Hudnut, R. W. Briggs, R. D. Koehler, and P. Jean (2010), Seismic hazard of the Enriquillo Plantain Garden fault in Haiti inferred from palaeoseismology, Nature Geosci., 3, 789-793, doi:10.1038/ngeo991.

    Saint Fleur, N., Y. Klinger, N. Feuillet (2020), Detailed map, displacement, paleoseismology, and segmentation of the Enriquillo-Plantain Garden Fault in Haiti, Tectonophysics, 778, 228368.

    Symithe, S. J., E. Calais, J. S. Haase, A. M. Freed, and R. Douilly (2013), Coseismic slip distribution of the 2010 M 7.0 Haiti earthquake and resulting stress changes on regional faults, Bull. Seismol. Soc. Am., 103, 2326–2343.

    Toda, S., and Stein, R. S. (2020), Long‐ and short‐term stress interaction of the 2019 Ridgecrest sequence and Coulomb‐based earthquake forecasts. Bull. Seismol. Soc. Amer. 110, 1765-1780.

    USGS (2021), Finite Fault model for 14 August 2021 M 7.2 Nippes, Haiti, Earthquake
    https://earthquake.usgs.gov/earthquakes/eventpage/us6000f65h/finite-fault

    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 10:26 pm on July 9, 2021 Permalink | Reply
    Tags: "Tectonic mystery swirls as earthquake rocks California-Nevada border", Decades of paleoseismic and tectonic studies have revealed dozens of faults throughout the Walker Lane some with evidence of large prehistoric earthquakes that likely exceeded magnitude-7.0., In the last three years far more moderate earthquakes have occurred along the Walker Lane Fault system than any other single fault system in the western United States., More than 100 aftershocks above magnitude 2.5 have rocked the region., On the afternoon of July 8 2021 a magnitude-6.0 earthquake rocked much of central California and western Nevada., temblor, The Walker Lane is a diffuse zone of normal and strike-slip faults. It follows an approximately 60-mile (100-kilometer)-wide swath along the Eastern Sierras and California/Nevada border., This earthquake originated in the seismically busy Central Walker Lane between Yosemite National Park in California and Carson City Nevada.   

    From temblor : “Tectonic mystery swirls as earthquake rocks California-Nevada border” 

    1

    From temblor

    July 9, 2021
    Ian Pierce-University of Oxford (UK)

    On the afternoon of July 8, 2021, a magnitude-6.0 earthquake rocked much of central California and western Nevada. Intense shaking that lasted as long as 20 seconds was reported 80 miles (~130 kilometers) away in Reno, while the Bay Area, Central Valley, Southern California and even Las Vegas all shook as well. Reports of damages are slowly trickling in from many of the remote communities nearest the shaking and videos of car-sized boulders on a major highway have gone viral. Since the mainshock less than 24 hours ago (at the time of posting), more than 100 aftershocks above magnitude 2.5 have rocked the region. More than 25,600 people have reported feeling shaking to the U.S. Geological Survey’s (USGS) Did You Feel It? website. If you felt the mainshock or any of the aftershocks — or if you didn’t — report them.

    1
    Map showing earthquakes that have rocked the Antelope Valley area, south of Lake Tahoe, since yesterday afternoon.

    This earthquake originated in the seismically busy Central Walker Lane between Yosemite National Park in California and Carson City Nevada, in the southernmost part of Antelope Valley. In the last three years, four large earthquakes — greater than magnitude 6.0 — have struck the Walker Lane region. What’s driving all this seismic activity and what does it mean for the earthquake hazards far from the famed San Andreas Fault?

    Busy Walker Lane

    The Walker Lane is a diffuse zone of normal and strike-slip faults. It follows an approximately 60-mile (100-kilometer)-wide swath along the Eastern Sierras and California/Nevada border, reaching from Death Valley and the Garlock Fault in the south to north of the Honey Lake Valley region. The Walker Lane Fault system accommodates roughly 20 percent of the 2-inch (50-millimeter) per year right-lateral shear between the Pacific and North American Plates, while the remaining 80 percent is accommodated along the more well-known San Andreas Fault system.

    2
    Annotated map showing locations of earthquakes greater than or equal to magnitude-6 in the Walker Lane region.

    The Walker Lane has been getting much attention recently, and for good reason. In the last three years far more moderate earthquakes have occurred along the Walker Lane Fault system than any other single fault system in the western United States. This earthquake is the fourth event larger than magnitude-6.0 since the 2019 Ridgecrest Earthquake Sequence that included magnitude-6.4 and magnitude-7.1 earthquakes, and the 2020 magnitude-6.5 Monte Cristo Range earthquake. In 2021 alone, yesterday’s earthquake joins a series of several other widely felt events ranging from magnitude 4 to 5 near Lake Tahoe and the Northern Sierras.

    Yet, the Walker Lane didn’t start popping off events in 2019. In 2016 the Nine Mile Ranch sequence produced three events of about magnitude-5.5 near Hawthorne, Nev., in less than an hour, following a similar sequence from 2011. In 2008, the Mogul sequence rocked Reno, Nev., with a magnitude-4.7 quake. The largest-known Walker Lane event was the 1872 magnitude-7.4 Owens Valley earthquake, which is roughly the maximum magnitude we expect of an earthquake along any single fault in this system.

    Decades of paleoseismic and tectonic studies have revealed dozens of faults throughout the Walker Lane some with evidence of large prehistoric earthquakes that likely exceeded magnitude-7.0. For example, the most recent earthquake along the Genoa Fault near Carson City occurred about 450 years ago (Ramelli et al., 1999). The fault running beneath the west shore of Lake Tahoe most recently ruptured about 5,500 years ago (Pierce et al., 2017).

    A tectonic mystery

    Shifting attention to the tectonics of the Central Walker Lane where this most recent magnitude-6.0 event occurred, an unresolved tectonic mystery swirls. Using high accuracy stationary GPS stations, we can observe — in real time — the crest of the Sierra Nevada sliding northwest at a rate of about 0.3 inches (7 millimeters) per year relative to Fallon, Nev., shearing the region spanning Antelope, Smith, and Mason Valleys. Yet, geologically speaking, we cannot find sufficient strike-slip faulting to account for this observed shear.

    3
    Overview of study area of Pierce et al., 2020, that includes Antelope Valley. Dark gray hillshades indicate lidar data. Red lines show mapped faults. Bold black lines show fault contacts between bedrock and alluvial sediments. Thin black lines come from the USGS Quaternary fault and fold database. Credit: Pierce et al., 2020, CC BY 4.0.

    While a number of hypotheses have been proposed to explain this mismatch, we expect that future large earthquakes will show complex, transient and discontinuous deformation, as opposed to long-lasting fault strands that produce the fault scarps, large offsets of features in the landscape, and other geomorphologic features we would require to measure long-term faulting rates (Pierce et al., 2020). This more subtle, less dramatic style of deformation was witnessed in the 2020 Monte Cristo Range earthquake, as well as other earlier Walker Lane events. Other explanations for the missing measurable shear that we expect based on GPS data include clockwise rotations of basins and bounding normal faults, and obliquely slipping faults that bound the rangefronts of the mountains in this area.

    The fault responsible for the July 8 magnitude-6.0 event produced a north-striking normal moment tensor — the beachball diagram seismologists use to determine both the orientation of a fault, and which way it moved. Normal faulting is consistent with the local patterns of faulting in Antelope Valley. In other words, the quake occurred on a north-striking fault that moves because of east-west directed extension, similar to what we would expect for the north-oriented Antelope Valley Fault that bounds the range. This fault does not have a significant oblique component, as one might expect if this range were accommodating right-lateral shear — the motion recorded by the San Andreas Fault, and the overall movement of the Walker Lane as recorded by GPS. This supports the conclusion of our 2020 paper suggesting this range does not exhibit oblique faulting — it is mostly normal.

    Underappreciated hazards

    All told, eastern California and western Nevada have much underappreciated earthquake hazards. While these hazards are well known to the earthquake science community, the public seems to view these moderate magnitude-5 to 6 events as “the big ones” when in reality, were the inevitable magnitude-7 event to occur in one of the rapidly developing communities of the region, the losses to life and property would be devastating.

    Everyone living in this region should not only keep an earthquake kit and have a plan for inevitable forthcoming quakes, but they should also make sure their homes are prepared for earthquakes. There are a number of cost-effective measures that can be readily applied by homeowners to mitigate damage, like securing hot water heaters to walls and securing foundations. Finally, these moderate events should serve as a warning to our community leaders, and communities should encourage business owners to retrofit the relatively large number of unreinforced masonry structures in many of the historic districts of Reno, Carson Valley, Truckee, and Tahoe.

    Remember, if you feel shaking, the U.S. Geological Survey says to drop, cover and hold on.

    References:

    Pierce, I. K., Wesnousky, S. G., & Owen, L. A. (2017). Terrestrial cosmogenic surface exposure dating of moraines at Lake Tahoe in the Sierra Nevada of California and slip rate estimate for the West Tahoe Fault. Geomorphology, 298, 63-71.

    Pierce, I. K., Wesnousky, S. G., Owen, L. A., Bormann, J. M., Li, X., & Caffee, M. (2020). Accommodation of Plate Motion in an Incipient Strike‐Slip System: The Central Walker Lane. Tectonics, 40(2), e2019TC005612. doi: 10.1029/2019TC005612

    Ramelli, A. R., Bell, J. W., Depolo, C. M., & Yount, J. C. (1999). Large-magnitude, late Holocene earthquakes on the Genoa fault, west-central Nevada and eastern California. Bulletin of the Seismological Society of America, 89(6), 1458-1472.

    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 1:21 pm on May 3, 2021 Permalink | Reply
    Tags: "Strong earthquake jolts Assam", , , , temblor   

    From temblor : “Strong earthquake jolts Assam” 

    1

    From temblor

    April 29, 2021

    Akash Kharita, Indian Institute of Technology (IN)

    A strong earthquake rocked the northeastern Indian state of Assam on Wednesday morning at 7:51 am local time. The National Centre for Seismology (NCS), India’s agency responsible for monitoring earthquakes via a regional network of seismic stations, determined that the magnitude-6.4 event struck 4.8 miles (7.7 kilometers) northwest of the town of Dhekiajuli and 26.7 miles (43 kilometers) west of Tezpur, a city on the banks of the Brahmaputra River. The NCS reports that the quake ruptured at a depth of 10.5 miles (17 kilometers). The United States Geological Survey and European Mediterranean Seismological Centre both report that the event registered as a magnitude-6.0 earthquake. They calculated this magnitude using teleseismic data collected from stations located more than approximately 620 miles (1000 kilometers) from the quake.

    1
    Earthquakes of magnitude-4.0 and larger in the Assam and surrounding region (Jan. 1960-Mar. 2020), along with the April 28 mainshock. Credit: National Centre for Seismology.

    Approximately 70 aftershocks, with magnitudes ranging from 2.3 to 4.9, have been detected by NCS within a day after the mainshock. These quakes appear to align along a roughly northwest-southeast trend near the mainshock. Aftershocks are common following large earthquakes, and become less frequent with time.

    The chief minister of Assam, Sarbananda Sonowal, urged people to stay alert. Prime Minister Narendra Modi also assured those in the area that India’s central government would provide all the help it could.

    As of now, there are no immediate reports of loss of life, though several videos show severe infrastructure damage in the city Guwahati, the town of Tezpur and state of Bengal.

    A quake in the Himalayan foothills

    The state of Assam lies in the northeastern arm of India, sitting south of the mountainous country of Bhutan and the rugged Indian state of Arunachal Pradesh. Nevertheless, Assam feels the effects of convergence between the Indian and Eurasian tectonic plates that drives up the mountains. The southernmost Himalayan thrust fault — the type of fault that successively built the Himalayan range by shoving Eurasia over India — defines the boundary between the two plates. The surface expression of this boundary, interchangeably called the Himalayan Frontal Thrust or the Main Frontal Thrust, runs through the northern part of Assam and has hosted several major earthquakes in the past, whereas relatively minor faults splice the state at different orientations.

    The Shillong Plateau, which lies south of Assam, complicates the region compared to other parts of the Himalayan range. According to Byron Adams, a Royal Society Dorothy Hodgkin Fellow at the University of Bristol, “It’s possible that the Indian plate behind the Shillong Plateau, which includes Assam, has low flexural strength, so it doesn’t bend easily under the load of either the overriding Eurasian plate or sediment coming from the rivers draining the range.” Instead, this part of the Indian plate breaks, with numerous faults slicing through the region at irregular angles, he says. “There may be more heterogeneities in the Indian crust in the east, so as the plate tries to subduct, it breaks instead of bending, creating more northwest-trending faults between the Himalayan range and the Shillong Plateau.”

    Because of the numerous active faults crisscrossing the region, the NCS classifies this area within its zone of highest seismic hazard (Zone 5).

    2
    Earthquake hazard zones in India. Credit: PlaneMad/Wikimedia.

    The Kopili Fault

    The mainshock likely struck near the Kopili Fault, according to a preliminary analysis by the NCS. This fault trends in a northwest-southeast direction, indicating it is a “minor” fault, though it’s still capable of substantial seismic activity. Scientists believe this fault hosted the 1869 magnitude-7.5 Chachar earthquake and the 1947 magnitude-7.3 Hajoi earthquake (Sutar et al., 2017). This fault may have played a role in a 1941 magnitude-6.5 event (Kayal et. al., 2010).

    According to Supriyo Mitra, a professor at the Indian Institute of Science Education and Research Kolkata Seismological Observatory, the Kopili fault zone moves with right-lateral strike-slip motion, meaning that the northeastern side of the fault moves to the southeast along a very steep fault surface. For reference, this is the same sense of motion along the famed San Andreas Fault. As the Shillong Plateau moves northward, says Mitra, that movement may be accommodated by the Kopili Fault zone.

    Adams points out that the focal mechanism produced by the United States Geological Survey indicates a substantial thrust component, along with right-lateral movement. “If you put some right-lateral shear on those northwest-trending faults between the Himalayan range and the Shillong Plateau, you might expect something like what just happened in Assam.”

    References

    Kayal, J. R., Sergei S. Arefiev, Saurabh Baruah, Ruben Tatevossian, Naba Gogoi, Manichandra Sanoujam, J. L. Gautam, Devajit Hazarika, and Dipak Borah. “The 2009 Bhutan and Assam felt earthquakes (Mw 6.3 and 5.1) at the Kopili fault in the northeast Himalaya region.” Geomatics, Natural Hazards and Risk 1, no. 3 (2010): 273-281.

    National Centre for Seimology Report on 28th April 2021 Earthquake (M 6.4), Sonitpur, Assam, https://seismo.gov.in/sites/default/files/pressrelease/Assam_EQ_Report_28Apr2021.pdf

    Sutar, A. K., Verma, M., Pandey, A. P., Bansal, B. K., Prasad, P. R., Rao, P. R., & Sharma, B. (2017). Assessment of maximum earthquake potential of the Kopili fault zone in northeast India and strong ground motion simulation. Journal of Asian Earth Sciences, 147, 439-451.

    Further Reading

    Clark, M. K., & Bilham, R. (2008). Miocene rise of the Shillong Plateau and the beginning of the end for the Eastern Himalaya. Earth and Planetary Science Letters, 269(3-4), 337-351.

    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 8:02 am on April 28, 2021 Permalink | Reply
    Tags: "Surprising recharacterization of earthquake risk along a strand of the San Andreas", , Banning strand of the San Andreas Fault, , , , Mission Creek strand of the San Andreas Fault, , , temblor   

    From temblor : “Surprising recharacterization of earthquake risk along a strand of the San Andreas” 

    1

    From temblor

    April 20, 2021
    Ben Wolman (@bythewolman)

    The San Andreas Fault (US) is as close to a celebrity as geological features can get — it even has a movie named in its honor.

    Since its formal identification in the late 19th century, the fault has been analyzed, dated, mapped and modeled by thousands of scientists. But its southernmost section, which is divided into strands like the frayed ends of a rope, still puzzles scientists.

    The northern and central sections of the San Andreas have ruptured relatively recently, geologically speaking (in 1906 and 1857, respectively), producing magnitude-7+ earthquakes (Fialko, 2006). The southernmost section, southeast of Los Angeles, however, last ruptured in 1726 and has accumulated significant strain since. This is partly why people often say it’s “overdue” for a big quake (though faults can’t really be overdue).

    A recent study published in Science Advances suggests that the Mission Creek strand of the San Andreas, which runs along the northeastern side of the Coachella Valley, is the dominant fault at this latitude, accounting for about 90% of the overall slip rate of the southern San Andreas Fault system. That means the Mission Creek strand — not the strands previously identified as accumulating the most strain — could host the next major earthquake on the southern San Andreas.

    1
    The southern San Andreas Fault consists of multiple strands. The Mission Creek strand may be a bigger risk for Southern California than previously thought. Credit: modified from Kimberly Blisniuk.

    Slipping and straining

    Slip rates describe the speed at which the two sides of a fault move relative to each other. Slip rates are typically ascertained through geologic measurements of landforms offset by fault movement, such as jags in alluvial fans, beheaded stream channels (those cut off from their headwaters), and vegetation lineaments (where dense vegetation meets less-dense vegetation in an abrupt line, likely due to a fault cutting off groundwater where the line occurs). Geodetic data obtained by ground motion observed in GPS or radar imaging can also be used to model slip rates.

    Previous geologic and geodetic data suggested that one piece of the San Andreas in the Coachella Valley called the Banning strand was likely responsible for the bulk of the slipping northwest through the San Gorgonio Pass. The Banning and Mission Creek strands run roughly parallel to one another. The new study investigates the slip rates from two new locations in the valley.

    Offset landforms

    Kimberly Blisniuk, an earthquake geologist and geochronologist at San Jose State University (US), and her team started by reconstructing and dating landform offsets in the Indio Hills (Banning) and Pushawalla Canyon (Mission Creek). They used lidar imaging and field mapping to determine the offset of ancient stream channels and other landforms. Then the team combined two different dating techniques — uranium-thorium dating of soil and beryllium-10 dating of surface exposures — to provide a minimum age estimate and a maximum age estimate for the landforms.

    The team noted that in Pushawalla Canyon, channels come out of a steep mountain front and hit the valley and aggrade in a unique stairstep-like terrace pattern, says Richard Heermance, a geologist at California State University-Northridge (US), who was not involved in the new research. By matching the deposits with their likely places of origin, and with “a distance and an age for each surface when they were just forming,” the team computed slip rates by simply dividing distance by age, Heermance says. The uniqueness of the Pushawalla Canyon landforms enabled this mapping, he adds. “That part of the story is great.”

    2
    Beheaded channels cut by a strand of the San Andreas fault. Credit: Kimberly Blisniuk.

    The landform changes and dating together indicate that the Mission Creek strand at this latitude, previously thought to be inactive, has hosted the most earthquakes in this region over the last 100,000 years, Blisniuk and her team reported.

    Slip on a different fault strand

    In addition, Blisniuk and her team found that the Mission Creek strand at Pushawalla Canyon appears to slip approximately 0.9 inches (21.6 millimeters) per year — compared to the Banning strand’s 0.1 inches (2.5 millimeters) per year. That means in the last 295 years, the Mission Creek strand has accumulated 20-30 feet (6-9 meters) of elastic strain, a measure of stress. Think of elastic strain like a rubber band pulled taut: If you stop pulling on the rubber band, strain is released and it can go back to its normal shape. But if it’s pulled too tight for too long, it will snap and release that strain in the form of energy. Rocks along a fault do the same, releasing the strain in an earthquake. Thus, the Mission Creek strand may instead hold the lion’s share of earthquake potential at Pushawalla Canyon.

    Risks to Los Angeles

    The findings could be important for the densely populated Los Angeles area. “Before, we only had this one path where a southern San Andreas Fault earthquake could rupture through the greater Los Angeles area,” Blisniuk says. “Now we’re seeing that actually, kind of like the [2019] Ridgecrest earthquakes, which occurred on faults that weren’t identified, there are faults that we’ve identified as likely inactive, that may still be active.”

    Future southern strand risk mapping

    “This study has highlighted the need for more detailed studies,” Heermance says, especially through San Gorgonio Pass northwest of the Banning and Mission Creek strands where much of the strain in this region is currently thought to be accumulating. But Heermance says the approximately 0.9 inches (21.6 millimeters) of annual slip found in the study cannot yet be definitively attributed to the entire Mission Creek strand northwest of Pushawalla Canyon: It’s still an open question, he says, noting that future fault mapping should help reduce the uncertainty.

    3
    Blisniuk doing field work along the southern San Andreas Fault. Credit: Thomas Rockwell, San Jose State University (US).

    Blisniuk agrees further landform offset analyses and dating of additional sites along the strands are needed. She says she’s excited by the promise of new data to be unearthed at these strands. “This is one of the best-studied faults in the world. And now with new technology and new dating techniques, we can test all of these [earthquake] models.” And those new data are suggesting that there’s so much to learn, and there’s so much to still investigate. “The past is the key to the present.”

    References

    Blisniuk, K., Scharer, K., Sharp, W.D., Burgmann, R., Amos, C., Rymer, M., 2021. A revised position for the primary strand of the Pleistocene-Holocene San Andreas fault in southern California. Sci Adv 7, eaaz5691. https://doi.org/10.1126/sciadv.aaz5691

    Fialko, Y., 2006. Interseismic strain accumulation and the earthquake potential on the southern San Andreas fault system. Nature 441, 968–971. https://doi.org/10.1038/nature04797

    Further Reading

    Guns, K.A., Bennett, R.A., Spinler, J.C., McGill, S.F., 2020. New geodetic constraints on southern San Andreas fault-slip rates, San Gorgonio Pass, California. Geosphere 17, 39–68. https://doi.org/10.1130/GES02239.1

    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 7:04 am on April 28, 2021 Permalink | Reply
    Tags: "Overdue? The future of large earthquakes in California", , , , , , , , , , temblor   

    From temblor : “Overdue? The future of large earthquakes in California” 

    1

    From temblor

    April 21, 2021
    Krystal Vasquez (@CaffeinatedKrys)

    With hundreds of known faults running through the state, California is no stranger to earthquakes. In fact, one occurs about every three minutes, though the majority of these are too small to be felt. But even with all this seismic activity, the state’s three major fault lines have remained eerily quiet. Evidence shows that the San Andreas Fault (US), San Jacinto and Hayward faults should produce a major earthquake roughly three or four times per century (Biasi and Scherer, 2019). Yet, the last one struck in 1918.

    This might not seem like a bad thing. After all, no one wants to experience a big earthquake. But seismologists know that with each passing year, these faults will continue to accumulate stress. Eventually, this stress will be released through a major earthquake — or maybe even several of them. It’s not a matter of if, but rather when this will happen. And given the state’s unusual shortage of large earthquakes, one could easily surmise that California’s well overdue.

    However, David Jackson, a geophysicist at the University of California-Los Angeles (US), is not quite convinced. “It may be just luck” that there has not been a major earthquake, he admits. Alternatively, there might be some unknown interaction between the fault lines that has gifted the state with a relatively peaceful century. But at the 2021 Seismological Society of America (US) Annual Meeting today, Jackson advocated for another possibility: perhaps this so-called “anomalous hiatus” doesn’t actually exist.

    Digging into Earth’s past

    The oft-spoken phrase, “Those who do not learn history are doomed to repeat it,” applies to earthquakes, too. Studying California’s past earthquakes can help scientists get a better idea of how much shaking the state might see in the future.

    They do this by digging trenches along active fault lines and searching for evidence of ground displacements or marks left behind on the shaken landscape. The gaps between these displacements tell a “micro-geologic story,” says Glenn Biasi, a geophysicist from the U.S. Geological Survey (USGS), who was not involved with the study. In other words, these trenches are used to reconstruct a timeline of past seismic events, which scientists can then use to calculate the likelihood that a major earthquake could occur within a subsequent time frame.

    1
    Digging a paleoseismic trench along the Hayward Fault. Credit: USGS.

    That’s why scientists have dug numerous trenches along California faults. “We have 31 places where we think we know about past earthquakes,” Biasi explains. “Those places have not produced an earthquake in 100 years.” Based on the data from these locations, it turns out the likelihood that there would be no evidence of a major earthquake in these locations during this timeframe is extremely low. “Many of us think that must mean something.”

    But in his presentation, Jackson casts some doubt on these “paleoseismological” studies. He says that not all earthquakes leave their marks and, on the flip side, “there may be other things that also give you a similar kind of displacement.” He specifically points to a study led by Nathan Onderdonk, a geologist at California State University-Long Beach (US), where Onderdonk concludes that one particular displacement might have been the result of a nearby earthquake or groundwater movement, among several other possibilities (Onderdonk et al., 2013). Based on this, Jackson argues that some displacements might be attributed to earthquakes even though weren’t actually caused by them. This would, in turn, cause scientists to overestimate the rate these events occurred in the past. “If, say the rate is only once a century or maybe once every 75 years, then if you go 100 years without having any event” our earthquake hiatus makes a lot more sense.

    His main conclusion, though, is that large earthquakes never stopped occurring. By combining instrumental seismic data (e.g. seismographs) and personal accounts of shaking, Jackson points out that there have actually been nine magnitude-7.0 earthquakes in the state since 1918 — they just don’t show up in the paleoseismic records. Biasi, however, says that comparing these different types of data is like comparing “apples and oranges” and explains that paleoseismic data look at specific points on the fault line, whereas the data Jackson used describes a much broader area.

    “We said that these [specific] sites on our biggest faults have a hiatus, not that there’s a general hiatus…These places haven’t broken in 100 years. Over there,” Biasi points to somewhere in the distance, “I don’t know.”

    2
    Annotated photograph (left) and cartoon (right) of offset sedimentary layers in a paleoseismic trench wall that cuts through a section of the San Andreas Fault. Credit: Kate Scharer, USGS.

    Don’t get complacent

    It seems the jury might still be out on what this gap in the paleoseismic record might mean. Are the California fault lines overdue? Maybe. But maybe “overdue” is the wrong way to frame this question.

    “The potential for strong shaking over most of California is real,” says Biasi, “and the probabilities are high enough that you can’t discount that it will happen in your lifetime.”

    Similarly, Jackson ends his presentation with: “We don’t need the compelling word ‘overdue’ to compel action,” and separately says that he doesn’t want to be interpreted as saying there’s no danger. Instead, he offers the following advice: “Make a plan…and then every time you hear the word earthquake, or you feel an earthquake, look at your plan and make an improvement… If you hear the word earthquake, and you don’t do something, then you’re overdue.”

    References

    Biasi, G. P., & Scharer, K. M. (2019). The Current Unlikely Earthquake Hiatus at California’s Transform Boundary Paleoseismic Sites. Seismological Research Letters, 90(3), 1168-1176

    Onderdonk, N. W., Rockwell, T. K., McGill, S. F., & Marliyani, G. I. (2013). Evidence for Seven Surface Ruptures in the Past 1600 Years on the Claremont Fault at Mystic Lake, Northern San Jacinto Fault Zone, California. Bulletin of the Seismological Society of America, 103(1), 519–541

    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 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 8:22 pm on April 20, 2021 Permalink | Reply
    Tags: "Undersea telecom cables detect ocean earthquakes", , , , , , , , temblor   

    From temblor : “Undersea telecom cables detect ocean earthquakes” 

    1

    From temblor

    April 20, 2021
    Lauren Milideo, Ph.D.

    Undersea telecom cables detect ocean earthquakes
    Posted on April 20, 2021 by Temblor

    Researchers used throwaway data from telecom companies to turn submarine telecommunications cables into deep-sea earthquake sensors.

    By Lauren Milideo, Ph.D., science writer, (@lwritesscience)

    Earthquakes on land often rattle a wide array of seismic sensors, giving researchers plenty of data to analyze. Using these data, seismologists gain a better understanding of how earthquakes occur and where they are more likely to strike in the future. Unfortunately, most of the planet is covered by water and very few seismic sensors monitor the vast oceans. Now, a new study [Science] explores whether underwater telecommunications cables can serve as stand-in sensors and monitor immense spans of Earth’s surface.

    1
    Over 70% of Earth’s surface is covered in water, where seismic monitoring equipment is rare. Credit: jack atkinson, Unsplash.

    A fresh approach

    The idea of using fiber-optic telecommunications cables to sense earthquakes is not new. Researchers have previously used so-called “dark fibers” — fibers not being actively used within a cable — on land to detect seismic waves and on a limited basis underwater. But until now, research utilizing submarine cables has taken place only on short bits of cable because dark fibers are so rare underwater, says Zhongwen Zhan, a seismologist at CalTech’s Seismological Laboratory. These cables are too expensive to have a large number of dark fibers available for other use. This limits the area over which cables can be used to detect earthquakes.

    Zhan and a team of researchers sought a different way to use optical-fiber cables to seismically monitor the oceans. Light waves used to transmit data long distances in cables travel in two perpendicular planes, allowing telecom companies to send a large amount of information at once, notes Zhan. The angle between the waves can change if the light signal is perturbed along its journey from one end of the cable to the other. Telecom companies monitor the information at the receiving end of the cables, says Zhan, to ensure that the signal received matches the signal sent and the two perpendicular signals have not interfered with each other along the way. Telecom companies have no other use for this information after this confirmation. The team realized this unused data may have other applications, Zhan says.

    Google’s submarine cable detects quakes

    The team turned to Google’s 6,525-mile-long (10,500-kilometer) Curie cable, which runs between Los Angeles, California and Valparaiso, Chile. This cable traverses underwater faults and a seismically active zone in the Pacific Ocean. The steady conditions on the seafloor — with few temperature fluctuations or other vibrations common on land — should cause little disruption in the signal traveling through submarine cables. Yet perturbations were still evident in the arriving signals, notes Zhan. The team found that some of these perturbations occurred at the same time as earthquakes detected by more traditional seismological means. The magnitude-7.4 quake that occurred near Oaxaca, Mexico, on June 23, 2020, was one such occurrence.

    1
    Deploying the Curie cable. Credit: Google Cloud.

    “The cool part about this research is that they don’t rely on installing extra instrumentation on cables that are not being used,” says University of Hamburg [Universität Hamburg](DE) Institute of Geophysics professor and seismologist Céline Hadziioannou.

    Because the recorded signal perturbation is integrated along the entire cable length, it is not currently possible to know exactly where along the cable a quake occurred using this type of sensing, says Hadziioannou. The researchers describe the potential use of signal perturbation information from several cables at once to determine a quake’s location. Hadziioannou says that “the approach is still very promising and could be quite powerful for future applications of early detection of the fact that there has been a remote earthquake.” Such information is useful, she says. If a large quake is detected along an undersea cable, existing earthquake early warning systems could be triggered before the seismic waves approach land.

    “Many of the bigger earthquakes are happening offshore,” Zhan says. “If you only have stations on land, then you are only looking at them from one side and you are really getting very limited understanding of those earthquakes.” He says that with the tremendous distance between these ocean quakes’ origins and land-based sensors, quick warnings of these quakes are not possible, as they would be if a sensor were located closer to the earthquakes.

    Another potential application of this method is tsunami warnings, but this is not yet certain. The researchers did detect ocean waves during their study period, Zhan says. “(A) tsunami is one kind of ocean wave, so we are hopeful that maybe one day it will work for detecting tsunamis,” he notes. No major tsunamis occurred during their nine months of observation, so the team does not yet know if submarine cables can detect tsunamis.

    Monitoring the vast oceans

    The research holds promise in expanding how seismologists are able to view and learn about these quakes happening so far from traditional seismic sensing networks. “This [submarine] network is already there,” says Zhan – a total of over 1.2 million kilometers, according to CNN. Using even a small percentage of these cables for geophysical research would greatly expand the seismic sensing coverage of Earth’s surface, Zhan notes.

    References

    Zhan, Z., M. Cantono, V. Kamalov, A. Mecozzi, R. Muller, S. Yin & J.C. Castellanos (2021). Optical Polarization-Based Seismic and Water Wave Sensing on Transoceanic Cables. Science. https://doi.org/10.1126/science.abe6648

    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 9:41 pm on March 12, 2021 Permalink | Reply
    Tags: "New Zealand sees exotic earthquake sequence", , , , QuakeAlertUSA-Early Warning Labs LLC, , temblor   

    From temblor: “New Zealand sees exotic earthquake sequence” 

    1

    From temblor

    March 12, 2021
    Hector Gonzalez-Huizar, Ph.D.,Center for Scientific Research and Higher Education at Ensenada [Centro de Investigación Científica y de Educación Superior de Ensenada, CICESE]
    Shinji Toda, Ph.D., IRIDeS, Tohoku University

    A mystifying series of earthquakes that struck north of New Zealand last week may have resulted from a unique form of seismic triggering.

    On March 4, 2021, a series of three large earthquakes struck within six hours of one another in the South Pacific. The earthquakes struck along 560 miles (900 kilometers) of the Kermadec trench, where the Pacific and Australian tectonic plates converge. The first shock — a magnitude-7.3 — struck at 2:27 am local time in the southern part of the trench, just off the northeastern coast of New Zealand’s North Island (Te Ika-a-Māui). The resulting pattern of seismic waves suggests that it was a complex rupture along multiple adjacent faults.

    Large earthquakes usually trigger aftershocks on nearby faults and in general, the largest aftershock is one unit of magnitude smaller than its mainshock — a magnitude-6.3 in this case. However, this earthquake was instead followed by both a magnitude-7.4 and a magnitude-8.1 earthquake along the same trench, just four and six hours later, respectively.

    This progressive increase in magnitude with time is rare for an individual sequence, particularly for earthquakes this large. When this occurs, the events are simply renamed and we call the largest earthquake in the sequence the mainshock (in this case the magnitude-8.1), and those preceding it are named foreshocks.

    1
    Red stars in the map represent the epicenters of the magnitude-7.3, 7.4 and 8.1 earthquakes that occurred on Mach 4, 2021. The blue arrow represents the direction of motion of the Pacific Plate relative to the Australian Plate. The inset figure shows a seismogram for that day, recorded by station ARMA.AU in Australia, highlighting the timing of the three earthquakes.

    The short time between the three earthquakes suggests that they were part of a same foreshock-mainshock-aftershock sequence; however, the large distance between the first and the other two earthquakes — more than 560 miles (900 kilometers) — makes it difficult to establish a clear connection.

    Triggering of earthquakes

    When a fault slips, or ruptures, during an earthquake, rock masses on either side of the fault are displaced. This shifting of mass results in a redistribution of stress within the crust. Ruptures occur because of stress applied to the fault surface and when stress changes, new earthquakes are sometimes triggered on nearby faults. The potential for this so-called “static triggering” following a large earthquake can be quantified using a parameter called Coulomb stress change. In general, a stress change greater than 0.1 bars imposed on a particular fault suggests a high probability that an earthquake will occur within a relatively short period of time (Hill, 2008).

    We estimate that the stress change imparted by the first of the earthquakes (the magnitude-7.3) on the rupture surface of the subsequent earthquakes (magnitude-7.4 and magnitude-8.2) was less than 0.01 bars. Therefore, it is very unlikely that the first earthquake caused the other two by static triggering. However, there are other mechanisms that might explain how the first earthquake could have indirectly triggered the other two, regardless of the large distance between them. One of these mechanisms is known as dynamic triggering.

    Dynamic triggering of the magnitude-7.4 earthquake

    When a fault slips, seismic waves radiate outward from the ruptured area. You feel these waves passing when the ground shakes during an earthquake. Not only can they damage buildings, but these waves can temporally increase the stress on other faults and trigger more earthquakes. Unlike static stress changes, these “dynamic” stress changes are transient, but they can be much larger at great distances.

    It is possible that the passing of the seismic waves generated by the magnitude-7.3 caused temporary changes on faults several hundred miles to the north, resulting in their triggering. Given their depth and location relative to known geologic features, the magnitude-8.1 likely occurred on the interface between the two tectonic plates (the so-called “megathrust surface”) and the magnitude-7.4 likely struck on a tear fault in the descending Pacific Plate. We estimate the dynamic stress change imparted by the seismic waves from the magnitude-7.3 on the tear of the rupture area of the magnitude-7.4.

    According to our calculations, stress change temporarily alternated between -0.1 to +0.1 bars as the seismic “wavetrain” from the magnitude-7.3 passed over the tear fault. This suggests that these passing seismic waves had a high potential to trigger the magnitude-7.4.

    3
    Model shows the temporal (dynamic) Coulomb stress change caused by the passing of the Rayleigh surface seismic waves, from the magnitude-7.3 earthquake, on a tear in the descending slab where the magnitude-7.4 earthquake occurred four hours later. Stress was obtained as in Hill (2008) and Gonzalez-Huizar and Velasco (2011).

    The seismic surface waves — a specific type of seismic wave that travels only along earth’s surface — generated by the magnitude-7.3 took only around four minutes to arrive at the location of the magnitude-7.4. Yet the magnitude-7.4 occurred around four hours later. In general, instances of dynamic triggering are difficult to prove, especially when the triggered earthquake does not occur instantaneously with the arrival of the seismic waves. However, cases of “delayed” dynamic triggering are well documented. Seismologists think that in these instances, the stress changes caused by the passing of seismic waves cause permanent damage to fault contacts, a slow slip event or the intrusion of fluids into the faults, resulting in a slowly progressing process that ends with the earthquake triggering (Parsons, 2005; Shelly et al., 2011; Castro et al., 2015).

    Interestingly, we found that this area has experienced several instanced of delayed dynamic triggering in the past. We found that at least four other remote, large (greater than magnitude-8.0), recent earthquakes potentially triggered moderate (greater than magnitude-5.0) earthquakes in this area. At least one of these moderate earthquakes occurred within 15 hours after the seismic waves from the triggering earthquakes passed through the area. By comparison, there were no moderate magnitude earthquakes there in the previous three days.

    Our preliminary results suggest that earthquakes at the Kermadec trench can be triggered by the small stress fluctuations, like those generated by the passing of seismic waves. Previous studies show that even the small stress changes generated by Earth tides are capable of controlling seismicity along the trench (Hirose et al., 2019), suggesting a high triggering susceptibility.

    4
    Map showing the epicenter (black stars) of recent large (greater than magnitude-8.0) earthquakes that potentially triggered moderate (greater than magnitude-5.0) earthquakes near the source of the magnitude-7.4 earthquake (within the area limited by the red square). Also, the epicenter of the three earthquakes discussed in this study are shown (red stars).

    Static triggering of the magnitude-8.1 earthquake

    The magnitude-7.4 earthquake appears to have triggered the magnitude-8.1 earthquake by static triggering. The distance between their epicenters is only about 30 miles (50 kilometers) and they occurred about 100 minutes apart. In order to investigate how the magnitude-7.4 and magnitude-8.1 earthquakes increased the probability of future earthquakes, we estimated the stress transferred by these two earthquakes to nearby faults. This requires knowing the location, geometry and orientation of the faults — information that can be obtained from the analysis of the seismic waves of past earthquakes that occurred on those faults. Faults or fault segments are represented in maps using focal mechanisms, often referred to as “beachballs,” which indicate the orientation and direction of slip of the fault section that generated the earthquake. A long fault is more accurately represented by a series of slightly different beachballs rather than by a simple plane. We calculated the stress imparted by the magnitude-7.4 and magnitude-8.1 earthquakes on surrounding beachballs. For the magnitude-7.4 earthquake, we find a dense ‘halo’ of red beachballs near the epicenter, indicating that this earthquake transferred significant stress to surrounding active faults, bringing them closer to failure. A simpler way of looking at the static stress transfer is shown in the inset in the lower right. The future magnitude-8.1 rupture surface has a larger area of red than blue, indicating a net increase in its failure stress.

    Below, we can see that after the magnitude-8.1, a core of blue beachballs highlights where the stress has dropped. But there are plenty of red beachballs as well, particularly north and south of the ruptured area. So, this sequence might not be over.

    5
    Map shows stress transferred to beachballs by the magnitude-7.4 (left panel) and the magnitude-8.1 earthquakes (right panel). The orientation of each beachball provides information on the orientation of the fault (or fault section) to which the stress is transferred, and the direction of the potential slip if an earthquake is triggered. Color represents the amount of stress transferred. Inset shows the stress resolved on the future plane of the magnitude-8.1 caused by the magnitude-7.4 earthquake.

    ________________________________________________________________________________________________________________________________________________

    References

    Parsons, T. (2005). A hypothesis for delayed dynamic earthquake triggering. Geophysical Research Letters, 32(4). doi:10.1029/2004GL021811.

    Hill, D. P. (2008). Dynamic stresses, Coulomb failure, and remote triggering. Bulletin of the Seismological Society of America, 98(1), 66-92. doi:10.1785/0120070049.

    Gonzalez‐Huizar, H., & Velasco, A. A. (2011). Dynamic triggering: Stress modeling and a case study. Journal of Geophysical Research: Solid Earth, 116(B2). doi:10.1029/2009JB007000.

    Shelly, D. R., Peng, Z., Hill, D. P., & Aiken, C. (2011). Triggered creep as a possible mechanism for delayed dynamic triggering of tremor and earthquakes. Nature Geoscience, 4(6), 384-388. https://doi.org/10.1038/ngeo1141.

    Castro, R. R., González‐Huízar, H., Ramón Zúñiga, F., Wong, V. M., & Velasco, A. A. (2015). Delayed dynamic triggered seismicity in northern Baja California, México caused by large and remote earthquakes. Bulletin of the Seismological Society of America, 105(4), 1825-1835. doi:10.1785/0120140310.

    Hirose, F., Maeda, K., & Kamigaichi, O. (2019). Tidal forcing of interplate earthquakes along the Tonga‐Kermadec Trench. Journal of Geophysical Research: Solid Earth, 124(10), 10498-10521. https://doi.org/10.1029/2019JB018088.

    Further Reading

    Stein, R. S., Rollins, C., Sevilgen, V., and Hobbs, T. (2019), M 7.1 SoCal earthquake triggers aftershocks up to 100 mi away: What’s next?, Temblor, http://doi.org/10.32858/temblor.038.

    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 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.

     
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