Tagged: Earthquake Alert system Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 11:57 am on May 30, 2021 Permalink | Reply
    Tags: "Weird Electromagnetic Bursts Appear Before Earthquakes – And We May Finally Know Why", , , Brief subtle anomalies in underground electrical fields lead up to an earthquake, Early Warning Labs Earthquake EWL Labs mobile app, , Earthquake Alert system, , , , , , ,   

    From Science Alert (AU) : “Weird Electromagnetic Bursts Appear Before Earthquakes – And We May Finally Know Why” 

    ScienceAlert

    From Science Alert (AU)

    30 MAY 2021
    DAVID NIELD

    1
    Credit: jamievanbuskirk/E+/Getty Images.

    For some time, seismologists have been aware of brief subtle anomalies in underground electrical fields leading up to an earthquake, sometimes occurring as soon as a few weeks before the quake happens.

    It’s tempting to think these electromagnetic bursts could be used to predict when a quake will strike. Up until now, however, the cause of the strange bursts hasn’t been clear.

    New research suggests that the key lies in the gases that get trapped in what’s known as a fault valve and can build up ahead of an earthquake. These impermeable layers of rock can slip across a fault, effectively creating a gate that blocks the flow of underground water.

    When the fault valve eventually cracks and pressure decreases, carbon dioxide or methane dissolved in the trapped water is released, expanding in volume and pushing the cracks in the fault. As the gas emerges, it also gets electrified, with electrons released from the cracked surfaces attaching themselves to gas molecules and generating a current as they move upwards.

    “The results supported the validity of the present working hypothesis, that coupled interaction of fracturing rock with deep Earth gases during quasi-static rupture of rocks in the focal zone of a fault might play an important role in the generation of pre- and co-seismic electromagnetic phenomena,” write the researchers in their published paper .

    1
    From the cited science paper.

    Using a customized lab setup, the team was able to test the reactions of quartz diorite, gabbro, basalt, and fine-grained granite in scaled-down earthquake-like simulations. They showed that electrified gas currents could indeed be linked to rock fracture.

    The type of rock does make a difference, the scientists found. Rocks including granite have lattice defects that capture unpaired electrons over time through natural radiation rising from below the surface, and that leads to a larger current.

    And the type of fault seems to have an effect as well. The study backs up previous research [Scientific Reports] from the same scientists into seismo-electromagnetics, showing how carbon dioxide released from an earthquake fault could be electrified and produce magnetic fields.

    Other hypotheses [Science] about the electromagnetic bursts include the idea that the rocks themselves could become semiconductors under enough strain and with enough heat, while other experts don’t think these weird bursts are predictors at all.

    Until an earthquake is actually predicted by unusual electromagnetic activity – activity that happens a lot on our planet as a matter of course anyway – the jury is still out. But if this idea is backed up by future research, it could give us a life-saving method for getting a heads up on future quakes.

    “As a result of this laboratory experiment, it might be possible to detect the electric signal accompanying an earthquake by observing the telluric potential/current induced in a conductor, such as a steel water pipe buried underground,” conclude the researchers.

    “Such an approach is now undergoing model field tests.”

    The research has been published in Earth, Planets and Space.

    _____________________________________________________________________________________

    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 University (US), and a year at California Institute of Technology (US), the QCN project is moving to the University of Southern California (US) 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

    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.

    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

    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.

    GNSS-Global Navigational Satellite System

    1
    GNSS station | Pacific Northwest Geodetic Array, Central Washington University (US)

    _____________________________________________________________________________________

    See the full article here .


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

    Please help promote STEM in your local schools.


    Stem Education Coalition

     
  • richardmitnick 7:04 am on April 28, 2021 Permalink | Reply
    Tags: "Overdue? The future of large earthquakes in California", , , , Earthquake Alert system, , , , , ,   

    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 4:15 pm on April 20, 2021 Permalink | Reply
    Tags: "Was Cascadia's 1700 earthquake part of a sequence of earthquakes?", , , Earthquake Alert system, , , , , , ,   

    From Seismological Society of America via phys.org : “Was Cascadia’s 1700 earthquake part of a sequence of earthquakes?” 

    From Seismological Society of America

    via

    phys.org

    April 20, 2021

    2
    Cascadia’s 1700 earthquake. Credit: https://www.wired.com/2010/01/0126northwest-quake-japan-tsunami/

    The famous 1700 Cascadia earthquake that altered the coastline of western North America and sent a tsunami across the Pacific Ocean to Japan may have been one of a sequence of earthquakes, according to new research presented at the Seismological Society of America (SSA)’s 2021 Annual Meeting.

    Evidence from coastlines, tree rings and historical documents confirm that there was a massive earthquake in the Cascadia Subduction Zone (US) on January 26, 1700. The prevailing hypothesis is that one megathrust earthquake, estimated at magnitude 8.7 to 9.2 and involving the entire tectonic plate boundary in the region, was responsible for the impacts recorded on both sides of the Pacific.

    But after simulating more than 30,000 earthquake ruptures within that magnitude range using software that models the 3-D tectonic geometry of the region, Diego Melgar, the Ann and Lew Williams Chair of Earth Sciences at the University of Oregon (US), concluded that those same impacts could have been produced by a series of earthquakes.

    Melgar’s analysis suggests that a partial rupture of as little as 40% of the megathrust boundary in one magnitude 8.7 or larger earthquake could explain some of the North American coastal subsidence and the January 26, 1700 Japan tsunami. But there could have also been as many as four more earthquakes, each magnitude 8 or smaller, that could have produced the rest of the subsidence without causing a tsunami large enough to be recorded in Japan.

    His findings do not rule out the possibility that the 1700 Cascadia earthquake was a stand-alone event, but “the January 26, 1700 event, as part of a longer-lived sequence of earthquakes potentially spanning many decades, needs to be considered as a hypothesis that is at least equally likely,” he said.

    Knowing whether the 1700 earthquake is one in a sequence has implications for how earthquake hazard maps are created for the region. For instance, calculations for the U.S. Geological Survey hazard maps are based on the Cascadia fault zone fully rupturing about half the time and partially rupturing the other half of the time, Melgar noted.

    “But are we really sure that that’s real, or maybe it’s time to revisit that issue?” said Melgar. “Whether there was a partial or full rupture fundamentally drives everything we put on the hazard maps, so we really need to work on that.”

    Since the first analyses of the 1700 earthquake, there have been more data from the field, repeated earthquake modeling of the Cascadia Subduction Zone and a better understanding of the physics of megathrust earthquakes—all of which allowed Melgar to revisit the possibilities behind the 1700 earthquake. Researchers also have been writing code for years now to simulate earthquakes and tsunamis in the region, in part to inform earthquake early warning systems like ShakeAlert.

    If there was a sequence of earthquakes instead of one earthquake, this might help explain why there is little good geologic evidence of the 1700 event in places such as the Olympic Mountains in Washington State and in southern Oregon, Melgar said.

    He noted, however, that these specific areas are difficult to work in, “and may not necessarily be good recorders of the geological signals that paleoseismologists look for.”

    Melgar’s models show that even a smaller Cascadia earthquake could cause a tsunami energetic enough to reach Japan. These smaller earthquakes could still pose a significant tsunami risk to North America as well, he cautioned. “They might be less catastrophic, because they don’t affect such a wide area because the rupture is more compact, but we’d still be talking a mega-tsunami.”

    He suggested that it could be valuable to revisit and re-do old paleoseismological analyses of the 1700 event, to gain an even clearer picture of how it fits into the overall earthquake history of the region.

    “Cascadia actually records earthquake geology much better than many other parts of the world,” Melgar said, “so I think that just going back with modern methods would probably yield a lot of new results.”

    See the full article here.

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Seismological Society of America (SSA) is an international scientific society devoted to the advancement of seismology and the understanding of earthquakes for the benefit of society. Founded in 1906, the society has members throughout the world representing seismologists and other geophysicists, geologists, engineers, insurers, and policy-makers in preparedness and safety.

    The society was established by academic, government, and other scientific and engineering professionals in the months following the April 18th San Francisco earthquake, with the first meeting of the Board of Directors taking place on December 1, 1906.

    The Seismological Society of America publishes the Bulletin of the Seismological Society of America (BSSA), a journal of research in earthquake seismology and related disciplines since 1911, and Seismological Research Letters (SRL), which serves as a forum for informal communication among seismologists, as well as between seismologists and those non-specialists interested in seismology and related disciplines.

    ________________________________________________________________________________________

    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", Earthquake Alert system, , , QuakeAlertUSA-Early Warning Labs LLC, ,   

    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.

     
  • richardmitnick 2:04 pm on February 21, 2021 Permalink | Reply
    Tags: "An Innovative Approach for Investigating Subduction Slip Budgets", A new 3D model offers a state-of-the-art look at the full spectrum of slip behaviors in the Nankai subduction zone off Japan., Earthquake Alert system, , , Nankai subduction zone is one of the most seismologically active regions on the planet., , ,   

    From Eos: “An Innovative Approach for Investigating Subduction Slip Budgets” 

    From AGU
    Eos news bloc

    From Eos

    19 February 2021
    David Shultz

    A new 3D model offers a state-of-the-art look at the full spectrum of slip behaviors in the Nankai subduction zone off Japan.

    1
    Shikoku Island (bottom center) in Japan is seen in this photo taken from the International Space Station in 2015. Credit: NASA.

    The Nankai subduction zone hugs the southeastern curve of Japan and is one of the most seismologically active regions on the planet. The combination of the region’s short seismic cycle—great earthquakes (magnitude 8 or greater) occurring roughly every 100–150 years—and its superb history of geophysical observations makes it an attractive natural observatory for scientists looking to study the evolution of subduction zones during and between great earthquakes. The last major quakes in the region occurred in the mid-1940s, and the decades since have offered opportunities for researchers to pursue innovative geodetic monitoring and modeling.

    In a new study, Sherrill and Johnson [Journal of Geophysical Research: Solid Earth] provide the most complete 3D coseismic and postseismic model of the Nankai subduction zone yet, using a new approach that relies on iteratively inverting vertical surface displacement data to characterize movement, or slip, along the fault. Slip at subduction zones displays a range of complex behaviors, such as slip during earthquakes, afterslip following major earthquakes, and episodic tremor and slow slip (ETS) events. Understanding the distribution of these slip behaviors in space and time relative to the area of a fault where earthquakes occur is crucial for assessing seismic hazards at subduction zones.

    For Nankai, the researchers teased apart the types of slip that have contributed most to the total slip budget (the amount of slip that must be accommodated in a subduction zone because of tectonic plate convergence). The model also offers new insights into the last large earthquakes at Nankai, allowing the researchers to estimate that the maximum slip during the 1940s events was 7.5 meters. Since then, afterslip has reached a maximum of 2.6 meters, they report.

    The slip budget at Nankai comprises coseismic slip, afterslip, short-term and long-term slow slip, and interseismic creep. Below eastern Shikoku Island, the researchers report that the slip budget is nearly met. However, below western Shikoku, there is a considerable deficit—about half the total budget—implying the potential for significant future earthquakes in that area. The study also revealed that long-duration afterslip occurred in the same area of the fault as ETS, an observation that provides new constraints on the frictional properties of this part of the subduction zone.

    Beyond what the research reveals about Nankai specifically, the work also offers a state-of-the-art approach for modeling geodetic data across a complete seismic cycle—a feat necessary for improving risk assessments and related policy decisions—that should be applicable to subduction zones around the world.

    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.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 9:32 am on February 18, 2021 Permalink | Reply
    Tags: "Q&A- ShakeAlert earthquake early warning system arriving in Pacific Northwest", , , Earthquake Alert system, , , , , ,   

    From University of Washington: “Q&A- ShakeAlert earthquake early warning system arriving in Pacific Northwest” 

    From University of Washington

    ShakeAlert earthquake early warning system arriving in Pacific Northwest.

    After years in development, an earthquake early warning system known as ShakeAlert is on the cusp of being released in Oregon and Washington. The system that spans the West Coast was launched in California in late 2019. It launches to the public in Oregon on March 11, the 10th anniversary of the Tohoku earthquake and tsunami, and in Washington in May.
    ________________________________________________________________________________________________________________________________________________
    February 17, 2021
    Hannah Hickey

    More Information
    Harold Tobin
    htobin@uw.edu

    Bill Steele,
    communications director at
    Pacific Northwest Seismic Network, at
    wsteele@uw.edu
    206-685-5880.

    After years in development, an earthquake early warning system known as ShakeAlert is on the cusp of being released in Oregon and Washington. The system that spans the West Coast was launched in California in late 2019. It launches to the public in Oregon on March 11, the 10th anniversary of the Tohoku earthquake and tsunami, and in Washington in May.

    The system was developed through a partnership between the University of Washington and other West Coast universities and the USGS working with state emergency management districts. The system uses ground sensors across the region to detect the first signals from a rupturing earthquake and then sends that information to computers and phones, providing seconds to tens of seconds of warning of an imminent earthquake.

    UW News sat down with Harold Tobin, professor of Earth and space sciences and director of the Pacific Northwest Seismic Network, to learn more.

    1
    Karl Hagel and Pat McChesney, field engineers with the Pacific Northwest Seismic Network team at the University of Washington, install earthquake monitoring equipment on the slopes of Mount St. Helens, with Mount Hood in the distance. Credit: Marc Biundo/University of Washington.

    How can people in the Puget Sound sign up for the test taking place in late February? And how can Washingtonians sign up for the actual earthquake early warning system when it goes live in May?

    Washington EMD and USGS have developed a simulated earthquake warning test message they will broadcast Feb. 25 on the Wireless Emergency Alert system, the nation’s universal alerting system. The test will evaluate how the WEA system performs for earthquake early warning in the Puget Sound area. For technical reasons, WEA does not distribute alerts as fast as we’d like for earthquake warnings. A delay of 30 seconds might not matter for an Amber Alert, but for earthquake warning systems that would mean many alerts would arrive after the strong shaking has begun.

    You have to opt in for the test, which is for users in Pierce, King and Thurston counties. Once ShakeAlert goes live in May, earthquake alerts will go to anyone in Washington who hasn’t opted out of the Wireless Emergency Alert system.

    There will be two other ways to get earthquake alerts. If you have an Android phone device, Google has embedded it in the mobile operating system in late 2020. So those devices in California are getting alerts now, and we expect Android alerts will go live in Washington in May. We hope other phone operating systems will follow suit. Another option will be to install on your device an app, like QuakeAlertUSA, built by one of the licensed ShakeAlert partners. We hope several of these apps will be available by the end of the year.

    Washington ShakeAlert is a collaboration between the USGS, Washington Emergency Management and the Pacific Northwest Seismic Network[PNSN]. Can you explain how the three groups collaborate?

    ShakeAlert is operated by the USGS in partnership with the PNSN and California seismic networks. The data that is generated to detect the earthquakes in Washington and Oregon comes from the PNSN, the seismic network operated out of the UW and the University of Oregon. We are direct partners in the research and development of this system. At the UW, we operate one of three computer systems that ingest the data and issue the alert messages; the others are at UC Berkeley and Caltech. There’s a strong partnership between the PNSN and the USGS on earthquake detection and the continuing development of the system that issues the warnings. Washington Emergency Management is responsible for public safety, and so they are determining the types of public alerts that will be released, the messaging, public education and appropriate responses.

    This is a great example of a partnership among all those entities. We are all working toward this same goal, of increasing earthquake awareness and public safety.

    The PNSN began testing the system back in 2015 with early adopters. What have you learned from that experience?

    A system like this is complicated, and will reach everyone, so we have to test it really extensively. We’re decreasing the number of false or missed alerts in our beta system. Just seeing more and more events has allowed us to improve the algorithms, to distinguish between a false alarm and a real signal, and to better pinpoint the magnitude and location of the earthquake. A typical time frame is now 2 seconds for our computers to decide on the location and magnitude of the earthquake and to generate the alert — the pace that that happens is unbelievable.

    Now that the system is about to go public, how will other businesses, schools, organizations or agencies be able to incorporate these alerts into their emergency plans?

    The USGS licenses partners to develop products that take the ShakeAlert message and can connect to other systems.

    ShakeAlert® License to Operate Partners

    Below is a list of License to Operate partners. They are currently the only partners with a License to Operate (e.g. have commercially or non-commercially available products or services that are powered by ShakeAlert®.

    Early Warning Labs: Josh Bashioum – info@earlywarninglabs.com

    Google: The Android Earthquake Alerts team – android-usgs-external@google.com

    MyShake™: Richard Allen – rallen@berkeley.edu

    RH2 Engineering: Rick Ballard – rballard@rh2.com

    San Francisco Bay Area Rapid Transit District (BART): Chung-Soo Doo – cdoo@bart.gov

    SkyAlert: Alejandro Cantu – alejandro@skyalertusa.com

    Valcom: Roger Steinberg – rsteinberg@valcom.com

    Varius: Dan Ervin – dan.ervin@variusinc.com

    Note: The USGS does not directly or indirectly endorse any product or service provided, or to be provided, by these Licensees.

    A number of those licensed partners offer systems that can be adopted, such as a box that can be hooked up to a school PA system and automatically issue a prerecorded message that alerts students to drop, cover and hold on. Any business that has staff in a facility can think about how they can incorporate earthquake early warnings into their own facility. ShakeAlert messages can also trigger automated actions to pause manufacturing processes, move elevators to the next floor and open the doors, close valves on reservoirs, and initiate other loss-reduction actions.

    What should someone do when they get their first “real” alert?

    When someone gets an alert, the appropriate action to take is to drop, cover and hold on. It’s important to get under a protective cover. Most injuries from earthquakes in the U.S. are not from the catastrophic collapse of a building but from falling objects – lights, ceiling tiles, etc.

    If you’re driving in a car, the appropriate action would be to pull over and stop the car, if possible. If you’re in a building, stay in a building. The message is really to brace yourself — drop, cover and hold on. That message, to pause and protect yourself, is key. (Washington Emergency Management has more tips here.)

    What about British Columbia? Will the earthquake early warning system extend across the border?

    Natural Resources Canada is working in parallel to develop an earthquake early warning system. We already use data from seismometers in Canada, and we incorporate that information in our alerts — earthquake waves don’t stop at the border.

    Can we expect any improvements or changes coming down the line?

    Yes, we’re improving the system all the time. We are going live with this system because we know that it works, but we’re also continuously improving the system. We have hundreds of seismic stations in place but we’re adding dozens more, so that we can optimize the network to detect earthquakes wherever they occur within the region.

    We’re also continuously improving the computer algorithms that detect the raw data and decide where and how big the earthquake is. Once it goes live, there will be no pause in improving the system. We would also love to add more offshore detection systems, since offshore quakes are a challenge to detect accurately.

    For me, this is an exciting example of science to action, of things that are driven by fundamental science and research in seismology that show the way to something that can do some tangible good for society — to increase public safety. It’s exciting to see that happening with the ShakeAlert system.

    ________________________________________________________________________________________________________________________________________________

    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 mobile app

    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.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    u-washington-campus
    The University of Washington is one of the world’s preeminent public universities. Our impact on individuals, on our region, and on the world is profound — whether we are launching young people into a boundless future or confronting the grand challenges of our time through undaunted research and scholarship. Ranked number 10 in the world in Shanghai Jiao Tong University rankings and educating more than 54,000 students annually, our students and faculty work together to turn ideas into impact and in the process transform lives and our world. For more about our impact on the world, every day.
    So what defines us —the students, faculty and community members at the University of Washington? Above all, it’s our belief in possibility and our unshakable optimism. It’s a connection to others, both near and far. It’s a hunger that pushes us to tackle challenges and pursue progress. It’s the conviction that together we can create a world of good. Join us on the journey.

     
  • richardmitnick 11:14 am on February 14, 2021 Permalink | Reply
    Tags: "Strong 7.1 Earthquake Rocks Northeast Japan Including Fukushima", Earthquake Alert system, Earthquakes are fairly common in Japan as one of the world's most seismically active areas., Fukushima Prefecture has been synonymous with the devastating nuclear disaster in 2011., Japan reports roughly 20% of the world's earthquakes with a magnitude of 6 or higher., , , , The jolting quake was also felt in Tokyo Japan's capital., The quake was centered 37 miles beneath the ocean bed., There are no dangers of tsunamis., With 14 aftershocks felt and almost 850000 households without power authorities report that no casualties or damage to property were reported as of yet.   

    From Science Times: “Strong 7.1 Earthquake Rocks Northeast Japan Including Fukushima” 

    Science Times

    From Science Times

    Feb 13, 2021
    Isabella Beltran

    1
    The fallen gate of a house is seen on a street in Koori, Fukushima Prefecture, on Feb. 14, 2021, after an earthquake with a magnitude of 7.3 struck northeastern Japan late on Feb. 13. Credit: Kyodo News.

    2
    A liquor shop’s manager clears the damaged bottles following an earthquake in Fukushima, northeastern Japan. Credit: Jun Hirata/Kyodo News/AP)

    February 13, 2021, Japan Meteorological Agency reports that a 7.1 earthquake rocked Northeast Japan at 10:07 pm JST. With no immediate reports of damage or casualties.

    With 14 aftershocks felt and almost 850,000 households without power, authorities report that no casualties or damage to property were reported as of yet.

    The jolting quake was also felt in Tokyo, Japan’s capital.

    Prime Minister Yoshihide Suga tells a press conference, “There have been no anomalies reported from any nuclear facilities. Everything is normal.”

    According to NHK TV, there are no dangers of tsunamis. The agency reports that the quake was centered 37 miles beneath the ocean bed.

    The Prime Minister states that currently, checks are being carried out to determine the number of injured, urging people not to venture outdoors in the meantime and to prepare for oncoming aftershocks.

    Chief Cabinet Secretary Katunobu Kato tells a separate news conference that roughly 850,000 households are left with no power in the area surrounding Tokyo and northern Japan.

    A spokeswoman for the Japan Meteorological Agency tells the press in Tokyo, “Where the tremor was felt the strongest, there is a higher risk of structural collapse and landslides.” Adding that residents should be cautious about tremors that result from the earlier 7.1 quakes.

    Fukushima: The Devastation in 2011

    Fukushima Prefecture has been synonymous with the devastating nuclear disaster in 2011, where the area was hit by a 9.0 magnitude earthquake–the strongest earthquake in Japan’s history. A tsunami followed soon after, leaving more than 15,000 residents dead and 2,500 others missing.

    The deadly tsunami slammed through the Fukushima Daiichi Nuclear Power Plant walls, knocking out power and causing 3 nuclear reactors to melt, spewing radioactive particles into the air.

    Chief Cabinet Secretary Kato says that the plant was currently being inspected with no concern of damage-causing tsunami, and no anomalies were reported on site after the 7.1 earthquakes. Investigations continue to ensure that there is no structural damage.

    The Tokyo Electric Power Company, which operates the plant, tweeted that there are no detected abnormalities or adverse effects from the recent Fukushima Prefecture earthquake after checking its facilities.

    As a sign of rebirth, Fukushima was due to host parts of the Summer Olympics set to take place in 2020. But due to the COVID-19 pandemic, the games were delayed.

    Earthquakes are fairly common in Japan, as one of the world’s most seismically active areas. Japan reports roughly 20% of the world’s earthquakes with a magnitude of 6 or higher.

    Earthquake Alert

    1

    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

    QCN bloc

    Meet the 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

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    About Us

    The Science Hub For The Internet…

    Sciencetimes.com prides itself in providing a complete informational and content package for science enthusiasts in the web who aim to remain updated and well-informed regarding a wide array of topics of their interest.

    We provide credible news & info., in-depth reference material about diverse subjects that matter to everyone. We are a source for original and timely science and research information as well as breaking news in the various fields we represent.

     
  • richardmitnick 1:48 pm on February 9, 2021 Permalink | Reply
    Tags: "Fifty Years Ago A Major Earthquake Shifted the Course of Seismology in SoCal", An under-appreciated fault along the San Gabriel Mountains suddenly and dramatically slipped., , , Caltech was very much in the lead of the transition., , Earthquake Alert system, , February 9 marks 50 years since the devastating 1971 San Fernando earthquake that rocked Los Angeles., , , , The network of seismometers that monitor ground shaking in Southern California was fledgling.   

    From Caltech: “Fifty Years Ago A Major Earthquake Shifted the Course of Seismology in SoCal” 

    Caltech Logo

    From Caltech

    February 08, 2021

    Written by
    Kimm Fesenmaier

    Technical Contact
    Robert Perkins
    (626) 395‑1862
    rperkins@caltech.edu

    1
    Credit: Caltech/USGS

    The 1971 San Fernando quake led the USGS and Caltech to join forces, expanding seismic monitoring through the region

    February 9 marks 50 years since the devastating 1971 San Fernando earthquake that rocked Los Angeles. The magnitude-6.6 temblor was the worst the region had experienced for decades. But out of the tragedy came a period of tremendous advances in earthquake science and also in increasing public safety during earthquakes in Southern California.

    Just seconds after 6 a.m. on February 9, 1971, a 12-mile section of an under-appreciated fault along the San Gabriel Mountains suddenly and dramatically slipped. The entire Los Angeles region was rattled, but the shaking was particularly violent in the northeastern corner of the San Fernando Valley. By its end, two large hospitals (including one that was just months old) lay destroyed, powerlines had fallen, gas lines had exploded, freeway overpasses had collapsed, and many older buildings were damaged beyond repair. In the end, 65 people lost their lives, more than 2,000 other individuals were injured, and more than $500 million in property damage was apparent.

    It might be hard to imagine today because good information is available at our fingertips almost immediately following any earthquake. But on that day, the network of seismometers that monitor ground shaking in Southern California was fledgling, and scientists knew very little about what actually happened during an earthquake.

    “People hadn’t even started to ask the important questions about how earthquakes really happen,” says Thomas Heaton (PhD ’78), professor of engineering seismology, emeritus, at Caltech. “The 1971 San Fernando earthquake marked a major transition in earthquake science, and Caltech was very much in the lead in that transition.”

    2
    North-Trending fracture pattern near the Sylmar Converter Station above the upon Van Norman Dam. The fracture was due to a landslide and the dam’s setting in extensive fill material. Credit: USGS/Public domain.

    The quake struck at the end of a period of significant urban expansion in Los Angeles, when the region’s first tall buildings had recently been constructed. One of the requirements for building such tall structures had been to keep a record of the shaking they experienced during earthquakes. As a result, the San Fernando earthquake was the first that was well-recorded by dozens of nearby seismometers.

    “This was the first time we really had a glimpse of what the shaking was like around a major earthquake,” explains Heaton. “It allowed us to really begin to understand what the earthquake process was like.”

    Heaton himself has made computer models of what happened during the 1971 quake—of what exactly happened along the fault. The models that best fit the actual records from the event turned out to be very different from what earthquake scientists would have expected at that time. Eventually those efforts, in combination with work on additional earthquakes, led to a completely new idea of earthquake physics: earthquakes unfold over time, with faults starting to slip in one place with the slip moving outward and migrating along the fault.

    There was also a new realization among scientists after the 1971 earthquake that the thrust faults along the mountain ranges to the north of the L.A. region, such as the San Fernando and Sierra Madre faults, could produce large-magnitude quakes. The focus before San Fernando had been on the San Andreas and Newport-Inglewood faults. When the 1994 Northridge earthquake happened and was nearly a twin to the San Fernando event, scientists knew much more about what to expect.

    Equally important after the quake, Heaton says, was the great sense among earthquake scientists and engineers that monitoring and reporting systems had to be improved. When the San Fernando quake hit, it knocked out power to most of the L.A. region. In the most badly damaged area in the San Fernando Valley, all communications went down, so it was difficult for emergency responders to know where to focus their efforts. Seismologists too were left virtually blind. Caltech’s Seismological Laboratory normally received records of shaking via the telephone lines, but those were down as well.

    “Our inability to respond to that earthquake really had a strong impact on me and many of my colleagues to try to build a system that would provide information during the emergency to help emergency managers know what to do,” says Heaton.

    Immediately after the 1971 earthquake, the U.S. Geological Survey (USGS), which had been operating in the Bay Area, was told to set up shop in Southern California. After all, the San Fernando earthquake had been by far the country’s most damaging earthquake since the 1906 San Francisco earthquake.

    Caltech welcomed the USGS with open arms, and together, Caltech researchers and the USGS have put many systems in place to reveal where the shaking was during an earthquake and its strength. Now, those systems are so fast that Southern California has an earthquake early warning system that can warn that shaking is on its way.

    “For the last 50 years we’ve had this incredibly strong relationship between the USGS and Caltech, and that has allowed the seismic networks in Southern California to both grow larger and to more naturally evolve to include the newest scientific ideas than they ever would have without it,” says Mike Gurnis, the John E. and Hazel S. Smits Professor of Geophysics and director of the Seismo Lab.

    Another major piece of the developments following the 1971 earthquake was the creation by the federal government in 1977 of a multi-agency program called the National Hazards Earthquake Reduction Program (NHERP).

    “It would be difficult to overstate the importance of NHERP for earthquake research, monitoring, and reporting in Southern California,” says Lucy Jones, a visiting associate in geophysics at Caltech who served with the USGS for more than 30 years. “It was created as part of the outcome of the 1971 earthquake, and it’s the main government program that’s funded earthquake work ever since, including the seismic network at Caltech and the USGS office in Pasadena. It’s also where the funding was added to bring about earthquake early warning.”

    For the public, perhaps the most important outcomes of the 1971 San Fernando event were the laws and changes to building codes that were put into place to make buildings safer during major earthquakes. Because the damage during the quake had been so horrible, one of the first changes was the adoption of new seismic standards for hospitals.

    Other changes took a bit longer. During the quake, the San Fernando Fault actually came to the surface of the earth and tore through people’s houses. Prior to the event there was nothing to prevent builders from constructing homes and businesses directly on top of active fault lines.

    But as Jones notes, there are two types of damage associated with earthquakes. “The damage from shaking can be stopped by building stronger buildings,” she says. “The danger from the fault can’t be stopped because the fault itself is moving.”

    3
    Clarence Allen answers questions about the San Fernando Earthquake during a press conference at the Seismological Laboratory on February 10, 1971. Credit: Caltech.

    After the 1971 earthquake, Clarence Allen (MS ’51, PhD ’54), the late Caltech geologist and geophysicist, went to Sacramento and explained to legislators that geologists know where the active faults are and that an earthquake like San Fernando would certainly happen again in California. In 1972, the California legislature passed the Alquist-Priolo Earthquake Fault Zoning Act, which prohibits building across active faults. “It was really because of Clarence spending the time and the effort to help people understand that geology could actually tell you where this was going to happen that this change was made,” says Jones.

    It took a lot more fighting and time to get the City of Los Angeles to require a change that seismologists identified as sorely needed after the 1971 earthquake: the requirement to retrofit unreinforced masonry buildings. During the earthquake, many of these unreinforced buildings suffered damage, including tragic collapses at a homeless shelter in downtown Los Angeles and at the Veterans Administration Hospital in San Fernando, where 49 people died. In 1981, the city required that about 10,000 unreinforced buildings either be retrofitted or torn down. In 1986, the state of California passed a law requiring that all jurisdictions catalog unreinforced masonry buildings and develop retrofitting programs.

    “In 1994, when the Northridge earthquake happened, nobody died in an unreinforced masonry building,” says Jones, “which is pretty amazing because that’s always been where people die in California earthquakes. So the 1971 earthquake certainly saved lives in the 1994 earthquake.”

    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

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus

     
  • richardmitnick 11:18 pm on February 2, 2021 Permalink | Reply
    Tags: "Petrinja Croatia earthquake-magnitude 6.4-moved crust 10 feet", Earthquake Alert system, , ESA Sentinel-1B satellite, InSAR-Interferometric Synthetic Aperture Radar- is a method of using imagery collected by a radar satellite to measure small ground motions., On December 29 2020 at 11:19 UTC a strong shallow earthquake rocked the central region of Croatia., , ,   

    From temblor: “Petrinja Croatia earthquake-magnitude 6.4-moved crust 10 feet” 

    1

    From temblor

    February 1, 2021
    A preliminary analysis shows that the fault that slipped in December’s destructive magnitude-6.4 Petrinja earthquake slipped about 10 feet (three meters).

    By Athanassios Ganas, National Observatory of Athens, Institute of Geodynamics
    Panagiotis Elias, National Observatory of Athens, Institute of Astronomy, Astrophysics, Space Applications and Remote Sensing
    Sotiris Valkaniotis, Koronidos Str., 42131, Trikala, Greece
    Varvara Tsironi, National Observatory of Athens, Institute of Geodynamics; University of Patras, Department of Geology
    Ilektra Karasante, National Observatory of Athens, Institute of Geodynamics
    Pierre Briole, École Normale Supérieure de Paris, PSL Research University, Laboratoire de Géologie

    Summary

    On December 29, 2020, at 11:19 UTC, a strong, shallow earthquake rocked the central region of Croatia. The epicenter was located near the town of Petrinja, about 25 miles (40 kilometers) to the south of the capital, Zagreb. The earthquake was a magnitude-6.4 on the moment magnitude scale according to U.S. Geological Survey (USGS). The effects of the earthquake were devastating in neighboring villages and towns. Seven people died and many others were injured.

    Here we present a preliminary analysis of the geodetic data that were gathered and processed as of January 20, 2021, and present preliminary estimates of the slip that occurred on the fault during the earthquake and subsequent aftershocks.

    InSAR, or Interferometric Synthetic Aperture Radar, is a method of using imagery collected by a radar satellite to measure small ground motions. During repeating passes of a satellite, Synthetic Aperture Radar (SAR) images are taken over an area. The technique is used to measure how much the ground has moved roughly vertically, or in the line-of-sight of the satellite, between each pass of the satellite. If images are taken before and after a major earthquake, InSAR can give a clue as to how much slip occurred on the fault. These images are freely distributed by the European Space Agency (ESA).

    Global Navigation Satellite System (GNSS) data from five ground stations surrounding the epicenter were provided by the EUREF Permanent GNSS Network (EPN). GNSS data comprise 3D ground-to-satellite distance measurements (at least four are necessary to compute a position on a sphere) that are highly accurate, therefore any change in the antenna position due to seismic wave arrivals is easily detectable.

    By comparing InSAR images taken 11 days before and the day after the magnitude-6.4 earthquake, we find that the ground across the fault moved about 18 inches (45 centimeters) in the line-of-sight direction. We assume that the majority of that motion occurred during the earthquake on December 29. In the seven days following the earthquake, the ground across the same fault moved about an inch (2 centimeters). We simulated faults with different parameters including length, depth, angle, amount of slip and others to find one that best fit these observed data.

    Our preliminary analysis indicates that the rupture occurred on an approximately five-mile-long (eight-kilometer) west-dipping right-lateral strike-slip fault located beneath the NW-SE mountain ridge that runs west of Petrinja. In this case, the fault slipped about 10 feet (three meters), which seems large but is not uncharacteristic of faults with strong frictional resistance and long recurrence intervals. The best-fitting upper edge of the fault rupture is at a shallow depth of just over half of a mile (one kilometer), which indicates that the rupture did not reach the surface. These results give us a better idea of where active faults are located in central Croatia, allowing for better estimates of future seismic hazards.

    Introduction

    Croatia is located in the northeast edge of the Adria-Eurasia collision zone, a well-known compressional area (Anderson and Jackson, 1987; Grenerczy et al. 2005; Benetatos and Kiratzi, 2006; Bennett et al. 2008; Herak et al. 2009; Métois et al. 2015). The kinematics of the plate motions are determined by the on-going collision of the Adria continental block with Eurasia following the closure of several oceanic basins during Cretaceous through Eocene – Oligocene and the formation of south verging orogens such as the Eastern Alps and the Dinarides. Central and northern Slovenia and Croatia are deforming by seismic slip along strike‐slip and thrust faults (e.g., Grenerczy et al. 2005; Ganas et al. 2008; Herak et al. 2009), and a belt of intense NE–SW shortening continues south along the coast from Croatia into Montenegro and Albania (Benetatos and Kiratzi, 2006; Bennett et al. 2008; Métois et al. 2015). Crustal shortening is accommodated by a combination of reverse-slip and strike-slip motions along active faults, especially in external Dinarides (Bennett et al. 2008; Herak et al. 2009). In terms of strain, the amount of crustal shortening between Adria and Eurasia is ~ 4 mm/yr according to Battaglia et al. (2004) and Bennett et al. (2008), based on inversion modeling from GNSS velocities. Crustal strain rates range from 10-30 ns/yr, increasing landwards towards Zagreb (Métois et al. 2015).

    The Mw=6.4 earthquake of December 29, 2020, 11:19 UTC occurred west of the town of Petrinja (Figure 1), along a NW-SE striking transcurrent fault, as indicated by the distribution of aftershocks (compiled by EMSC) and moment tensor solutions of seismological data. As of January 18, 2021, more than 486 aftershocks with 1.0≤ML<6.4 were recorded by EMSC (Figure 2). One day before the mainshock, two moderate-size foreshocks occurred. The first struck on December 28, 2020, at 05:28 UTC (Mw=4.8 GFZ), and was followed by a Mw=4.4 at 06:49 UTC. The moment tensor solutions of the mainshock (Table 1) indicate NW-SE strike-slip faulting in agreement with the regional tectonics. The aftershock sequence extends over a distance of 30 km oriented SE-NW, with most of the events occurring to the northwest of the mainshock (Figure 2a). The EMSC aftershock data (the cumulative rate plot; in days from main shock) show the rate of the sequence decreasing after January 3, 2021 (Figure 2c). The earthquake raised the probabilities for a strong event closer to Zagreb by a factor of three (Stein and Toda, 2021) because of Coulomb stress transfer to neighboring faults.

    2
    Figure 1. Location map showing shaded topography, the seismic fault (black rectangle & red line; this study), the USGS focal mechanism and the epicenter of the Petrinja December 29, 2020, earthquake (Mw=6.4). Red arrows indicate sense of relative motion across fault. Inset box indicates location of earthquake area within Croatia together with the location of EUREF/EPN/CROPOS stations (blue triangles).

    3
    Figure 2. Temporal evolution of the Petrinja aftershock sequence (source of data: EMSC). a) map of aftershocks through 18 January 2021 b) magnitude distribution with time and c) cumulative rate of seismicity. Blue lines in a) indicate fault traces after Basili et al. (2013).

    Sentinel-1 Interferograms

    We used both the ascending and descending images acquired by the European Sentinel-1 satellites on Dec. 18 and Dec. 30 on track 146, and on Dec. 29 05:02 UTC and Jan. 4, 2021 on track 124.

    ESA (EU) Sentinel-1B.

    The interferograms (Figure 3) were made using the Automatic Interferometric Processing Station (AIPS) at NOA and ESA’s SNAP software version 8.0. The digital elevation model (DEM) used for the processing is the Shuttle Radar Topography Mission (SRTM) 1 Arc-Second Global (Digital Object Identifier number: /10.5066/F7PR7TFT). We enhanced the signal-to-noise ratio by applying the adaptive power spectrum filter of Goldstein and Werner (1998) with a coherence threshold of 0.3. The quality of the interferograms varies, both in terms of coherence and tropospheric noise. The interferograms show more than 15 fringes corresponding to ground deformation both west and east of Petrinja resembling the “butterfly” pattern, characteristic of strike-slip ruptures (e.g., Massonet et al. 1993). The interferograms (Figure 3) show an asymmetric, four‐lobed pattern, centered on a NW‐SE oriented discontinuity that is nearly coincident with an incoherent band in the interferograms. On the ascending interferogram (Figure 3, left panel; track 146), the western lobes are larger in size than those in the east, with the north‐west quadrant moving towards the satellite (along the so-called line-of-sight; l.o.s.) by ∼45 cm. The sense of ground motion across the discontinuity (the fault) indicates right-lateral rupture, in agreement with published moment tensor solutions (Table 1). East of the discontinuity, the phase changes are smaller, but spread out over a wide area. These range changes are due to the co-seismic displacement on either side of the fault – although we cannot rule out the possibility of rapid postseismic deformation, we expect such an effect to be small. We also note that while far-field interferometric fringes east of the main rupture (footwall) are consistent with the modeled dextral slip, fringes closer to the rupture are less consistent (or missing) – a hint of possible large scale gravitational displacements due to strong ground shaking such as lateral spreading.

    The absolute value of the interferometric fringes is estimated by a) the zero of the observations as it appears in the far field (although disturbed by the troposphere) b) the compatibility of this zero with the prediction of the forward model at the first order and c) the joint compatibility of the observations from ascending and descending tracks. After modelling, the seismological moment and the geodetic moment are very consistent. This is an additional indication that the zero was estimated correctly. We suggest that with this method, the zero-motion estimated is correct within ±5 mm (~1/5 of a fringe). We extracted the l.o.s. displacements by picking the fringes on Figure 3 at 511 (329 ascending and 182 descending) locations in total. The fringe pattern is interpreted as a result of co-seismic motion along a dextral strike-slip fault, running NW-SE and dipping to the west.

    4
    Figure 3. The coseismic interferogram (wrapped phase; cropped swath) over Petrinja, Croatia. Black arrows indicate the satellite azimuth direction and the line‐of‐sight (l.o.s.) look direction. Left panel shows the image pair Dec. 18-Dec.30, 2020 (ascending orbit). Right panel: Dec. 29-Jan. 04, 2021 (descending orbit).

    Finally, one of the exceptionally unique observations from this earthquake is the large number of fringes. Inversion modelling allows us to estimate parameters that usually cannot be estimated, in particular the azimuth and dip angles, the fault width and the rake. So, InSAR adds value and this is very marginally depending on the location uncertainties on the zero of the fringes.

    Co-seismic motion of the GNSS stations

    We analyzed the data of five GNSS stations belonging to the EUREF/EPN public network (Figure 1). The stations are located between 108 km and 209 km from the epicenter (Figure 1) and could have detected co-seismic motions, although marginally, as documented by scaling relationships between earthquake magnitude and ground displacements (Melgar et al. 2015; Ganas et al. 2018). The data comprise dual-frequency observations (pseudorange and phase; 30-s interval) supplied as daily files (format rinex v2.11 & v3.04). The processing was performed using the CSRS (Canadian) online processing PPP service. The coseismic displacements are listed in Table 2 (using data for the period Dec. 15, 2020 – Jan. 5, 2021), and Figure 4 shows the time series at CAKO (Cakovec, Croatia). The GNSS displacements are very small (less than 1 mm) at the horizontal components except for station CAKO where a motion of ~2.1 mm towards the south was detected. CAKO is located to the NE of the epicenter (Figure 1), so this motion is in agreement with rupture kinematics. The offsets at the vertical component are up to an order of magnitude less than the error (Table 2), as expected given the distance of the stations to the epicenter and the kinematics of the rupture. We could not see in the GNSS data evidence for any pre- and/or post-seismic deformation, and in particular there is no offset at the time of the large foreshock on December 28, 2020, 05:28 UTC (Mw=4.8 GFZ). In consequence, we assume that the interferograms (Figure 2) contain coseismic signal only with insignificant post-seismic fault slip.

    5
    Figure 4. Position time series (E, N, Up) of station CAKO (see location in Figure 1) normalized for clarity. The co-seismic offsets are the following: dE = 0.4 mm, dN = -2.1 mm and dU = +0.4 mm. The red vertical lines indicate the timing of the main shock.

    Fault model

    We use the InSAR l.o.s. displacements to estimate the fault parameters assuming that a rectangular source buried in a homogeneous elastic half-space and homogeneous slip. Our inversion approach finds the geometry and kinematics (strike and dip-angle) of best-fitting fault model. We invert the l.o.s. InSAR ground displacements using the code inverse6 (Briole, 2017). The modelling allows us to constrain seven parameters: the 3D location of the fault-top center, the fault azimuth, length and width and the amount of slip. Because of the quality and density of fringes we could invert for almost all the parameters including the angles, which is rare. The fault dip-angle of 76° was constrained by the seismological moment tensors (Table 1). The fault width is also constrained despite the lack of GNSS points in the near field because the quality of the fringes is very high and their azimuthal coverage is perfect. Our best-fitting model is with a right-lateral rupture of 8 km length and 5.1 km width, striking N129°E, (Figure 5).

    The best- fitting model produced a scenario where a) the center of the top of the fault is located at 16.233°E, 45.426°N, b) the depth of the upper edge of the fault is 1.3 km below the surface, c) the fault is 5.1 km wide, d) the fault is 8 km long, e) the fault azimuth is N129°E (which is consistent with the focal mechanisms and with the geomorphology of the area) and f) the fault dips 76° to the southwest. The fit to the fringes is better with this steep dip angle than with a purely vertical fault. This is consistent with the focal mechanisms. The rupture does not appear to reach the surface and if it does somewhere undetected along strike, the amount of slip drops close to zero within the first 1 km beneath the surface.

    The rupture area is small for an event of this magnitude, and therefore the finite slip is large; it is comparable to the case of the 2003 Bam earthquake (Mw=6.6; Peyret et al. 2007) or the 2011 Christchurch event (Mw=6.2; Elliott et al. 2012). However, as our model assumes a uniform slip, the model suggests that most of the slip (and therefore the energy) was released in a main patch (asperity). The right-lateral slip equals 3.2 m, which is larger than average for this magnitude. There was also a small 0.2 m component of reverse slip, which is consistent with the seismological rake of the focal mechanisms (around 172°-176°) and also with the topography (the NW-SE ridge). We obtained a geodetic moment tensor (4.45 × 10^18 N m) that is very consistent with the seismological moment tensors (Table 1). We note that in analyzing the solution space of nearly 3500 inversions, we found that all rupture lengths between 8 and 9 km, all widths between 5 and 6 km and all strike-slip amounts between 2.7 and 3.5 m are possible, with the product of the three being constant (to comply with the derived geodetic moment).

    6
    Figure 5: Synthetic interferograms (lower panel) corresponding to our best-fitting fault model (surface projection of the fault in lower left; white rectangle). The fault dip-direction is towards west thus the Petrinja – Sisak area comprises the footwall block.

    Post-seismic deformation and Fault afterslip

    After large earthquakes, post-seismic deformation is often observed. This can be from a relaxation in the volume due to the viscous rheology of the crust and/or from afterslip either on the fault plane or in the immediate vicinity, as the two blocks on either side of the fault do not stop moving (for example a ~3 cm motion was detected by GNSS following the Zakynthos earthquake over a 21-day period; Ganas et al. 2020). Constraining with geodetic or other data the nature of the physical processes producing post-seismic displacements is usually a difficult task and is often unsuccessful. The Petrinja earthquake was followed by hundreds of aftershocks (Figure 2) and it is highly probable that many of them occurred on the seismic fault or its extension into the lower crust or along neighbouring segments along strike. The slip associated with these aftershocks is termed afterslip and it was also imaged by InSAR (Figure 6). In the case of this earthquake, the sharp phase transition across the NW-edge of the fault, in correspondence with the co-planar rupture plane, strongly supports a model of localized afterslip rather than distributed deformation in the volume. The afterslip has occurred by aftershocks (Figure 2) and some possible slow aseismic slip in the shallow crust, where the main rupture did not reach because of the lack of frictional resistance at shallow depths (Marone and Scholz, 1988). The InSAR sharp imaging of the afterslip on the NW edge of the rupture is in the same direction (right-lateral) as the main rupture and reached 2 cm (relative motion along l.o.s.) within one week. Moreover, the location of afterslip is in agreement with the location of most aftershocks (Figure 2). As postseismic deformation is often localized around the rupture zone, rapid post-slip imaging could help visualize the fault rupture trace and its geometry (Figure 6). In the Petrinja case, we mapped a curved shape of the post-seismic deformation at the NW-end of the main rupture, which highlights the non-planarity of faults in nature.

    Therefore, results from InSAR track 073 suggest an extension of the deformation (afterslip) about 7 km towards the north and 5 km to the south of the main fault rupture (Figure 6). We note that other InSAR pairs either lacked in quality or had inconvenient time frames (for example, track 124 acquisition in the opposite orbit of 73 shown in Figure 6 was not acquired on January 5, 2021), therefore missed a direct comparison with track 73 afterslip results (2nd image obtained on January 6, 2021). Indeed, the first post-seismic descending orbit acquisition was acquired in January 10, 2021.

    7
    Figure 6. InSAR maps (track 073) showing non-planar afterslip during the period December 31, 2020 – January. 6, 2021. Left: unwrapped post-slip interferogram (l.o.s. displacement). Right: interpretation overlay of fault trace for main slip (model polygon) and afterslip (red traces).

    High rate GNSS and dynamic displacements

    We processed high-rate (1-s) GNSS data records from station BJEL about 70-km east of the epicenter (Fig. 1). This station is part of the CROPOS network of Croatia. The station is located at an appropriate distance so that we can clearly detect the body wave arrivals and identify the initiation of ground motion. This is because when the antenna moves during an earthquake, the position changes can be calculated to obtain displacement seismograms (e.g. Bock et al. 2011; Ruhl et al. 2018). The GNSS data comprise phase and range observables of GPS, GLONASS and GALILEO constellations. We processed the data in kinematic mode at the CSRS-PPP platform using an elevation cut-off of 7.5°. We obtained three-component displacement waveforms that demonstrate cm-size ground motions immediately following the arrival of S-waves (Fig. 7). The dynamic displacement reached 7 cm peak-to-peak on the East-west component. The shaking lasted about 150 s.

    8
    Figure 7. Displacement waveform (East component) of GNSS station BJEL in Bjelova city (Croatia), showing ground motion due to the 29/12/2020 Petrinja M6.4 earthquake. The station is located 70 km to the NE of the epicentre (see Fig. 1 for location).

    Conclusive statements

    • The 2020 Petrinja earthquake ruptured a segment of a fault that is shorter than average and with larger slip. This may at first glance be seen at odds with expected rupture sizes given the moment magnitude of the earthquake (Mw=6.4). However, the scaling relations published in the literature are only averages and the departure from those relations can easily reach 50% if not more. This event is a good example of the wide range of estimates of rupture length and slip. Indeed, in this case all parameters of the fault are well constrained by InSAR modeling. This happened thanks to the full azimuthal coverage with both ascending and descending data of good quality, which is uncommon.

    • The European database of seismogenic sources (EDSF) fault database needs to be modified, as the seismic fault dips towards the west and not towards east as was modelled. Additionally, the EDSF composite seismogenic fault surface trace deviates significantly from the 2020 rupture and mapped trace from InSAR.

    • Analysis of GNSS waveforms revealed that horizontal ground motion reached 7 cm (peak-to-peak).

    • The InSAR imaging of the 7 km afterslip on the NW-edge of the rupture, and in particular the curved shape of the post-seismic deformation, highlights the non-planarity of faults in nature.

    Acknowledgements: We thank Ross Stein, Jen Schmidt, Vanja Kastelic and Ina Cecic for comments and discussions. We are indebted to ESA, Geohazards Lab and Terradue for providing access to Geohazards Exploitation Platform (GEP) for InSAR cloud processing. Figure 2 was done with software ZMAP (Wiemer, 2001). GNSS data were provided by the EPN-EUREF network. HR-GNSS data were made available by Marijan Marjanovic (CROPOS).

    References [with some links and reference pointers to articles and science papers]

    Anderson, H. and Jackson, J. 1987. Active tectonics of the Adriatic Region. Geophysical Journal of the Royal Astronomical Society, 91: 937-983. https://doi.org/10.1111/j.1365-246X.1987.tb01675.x

    Basili R., Kastelic V., Demircioglu M. B., Garcia Moreno D., Nemser E. S., Petricca P., Sboras S. P., Besana-Ostman G. M., Cabral J., Camelbeeck T., Caputo R., Danciu L., Domac H., Fonseca J., García-Mayordomo J., Giardini D., Glavatovic B., Gulen L., Ince Y., Pavlides S., Sesetyan K., Tarabusi G., Tiberti M. M., Utkucu M., Valensise G., Vanneste K., Vilanova S., Wössner J. 2013. The European Database of Seismogenic Faults (EDSF) compiled in the framework of the Project SHARE. http://diss.rm.ingv.it/share-edsf/, doi: 10.6092/INGV.IT-SHARE-EDSF

    Battaglia, M., Murray, M. H., Serpelloni, E., and Burgmann, R. 2004. The Adriatic region: An independent microplate within the Africa-Eurasia collision zone, Geophys. Res. Lett., 31, L09605, doi:10.1029/2004GL019723.

    Benetatos, C., and Kiratzi, A., 2006. Finite-fault slip models for the 15 April 1979 (Mw7.1) Montenegro earthquake and its strongest aftershock of 24 May 1979 (Mw6.2): Tectonophysics, v. 421, p. 129–143, doi: 10.1016/j.tecto.2006.04.009.

    Bennett, RA. S. Hreinsdóttir, G. Buble, T. Bašić, Ž. Bačić, M. Marjanović, G. Casale, A. Gendaszek, D. Cowan, 2008. Eocene to present subduction of southern Adria mantle lithosphere beneath the Dinarides. Geology, 36 (1): 3–6. https://doi.org/10.1130/G24136A.1

    Bock, Y., Melgar, D. and Crowell, B.W., 2011. Real-time strong-motion broadband displacements from collocated GPS and accelerometers. Bulletin of the Seismological Society of America, 101(6), pp.2904-2925

    Briole, P. 2017. Modelling of earthquake slip by inversion of GNSS and InSAR data assuming homogenous elastic medium. Zenodo, http://doi.org/10.5281/zenodo.1098399

    Elliott, J. R., Nissen, E. K., England, P. C., Jackson, J. A., Lamb, S., Li, Z., et al. 2012. Slip in the 2010–2011 Canterbury earthquakes, New Zealand. Journal of Geophysical Research, 117, B03401. https://doi.org/10.1029/2011JB008868

    Ganas, A., Gosar, A., and Drakatos, G. 2008. Static stress changes due to the 1998 and 2004 Krn Mountain (Slovenia) earthquakes and implications for future seismicity, Nat. Hazards Earth System Science, 8, 59-66. https://www.nat-hazards-earth-syst-sci.net/8/59/2008/

    Ganas, A., Andritsou, N., Kosma, C., Argyrakis, P., Tsironi, V., Drakatos, G., 2018. A 20-yr database (1997–2017) of co-seismic displacements from GPS recordings in the Aegean area and their scaling with Mw and hypocentral distance. Bull. Geol. Soc. Greece, 52, 98–130, doi:10.12681/bgsg.18070.

    Ganas, A., Briole, P., Bozionelos, G., Barberopoulou, A., Elias, P., Tsironi, V., Valkaniotis, S., Moshou, A., Mintourakis, I., 2020. The 25 October 2018 Mw= 6.7 Zakynthos earthquake (Ionian Sea, Greece): a low-angle fault model based on GNSS data, relocated seismicity, small tsunami and implications for the seismic hazard in the west Hellenic Arc. Journal of Geodynamics, 137, 101731. doi: https://doi.org/10.1016/j.jog.2020.101731

    Goldstein, R. M.; Werner, C. L. 1998. Radar interferogram filtering for geophysical applications. Geophys. Res. Lett. 25(21), 4035-4038.

    Grenerczy, G., Sella, G., Stein, S., and Kenyeres, A., 2005. Tectonic implications of the GPS velocity field in the northern Adriatic region: Geophysical Research Letters, v. 32, doi: 10.1029/2005GL022947

    Herak, D.; Herak, M.; Tomljenovi´c, B., 2009. Seismicity and earthquake focal mechanisms in North-Western Croatia. Tectonophysics, 485, 212–220.

    Marone, C., and Scholz, C.H., 1988. The depth of seismic faulting and the upper transition from stable to unstable slip regimes. Geophysical Research Letters, v. 15, p. 621–624.

    Massonnet, D., M. Rossi, C. Carmona, F. Adragna, G. Peltzer, K. Feigl, and T. Rabaute, 1993. The displacement field of the Landers earthquake mapped by radar interferometry, Nature, 364, 138–142.

    Melgar, D.; Crowell, B.W.; Geng, J.; Allen, R.M.; Bock, Y.; Riquelme, S.; Hill, E.M.; Protti, M.; Ganas, A. 2015. Earthquake magnitude calculation without saturation from the scaling of peak ground displacement. Geophys. Res. Lett., 42, 5197–5205, doi:10.1002/2015gl064278.

    Métois, M., D’Agostino, N., Avallone, A., Chamot‐Rooke, N., Rabaute, A., Duni, L., Kuka, N., Koci, R., and Georgiev, I. 2015. Insights on continental collisional processes from GPS data: Dynamics of the peri‐Adriatic belts, J. Geophys. Res. Solid Earth, 120, 8701– 8719, doi:10.1002/2015JB012023.

    Peyret, M., J. Chéry, Y. Djamour, A. Avallone, F. Sarti, P. Briole, M. Sarpoulaki, 2007. The source motion of 2003 Bam (Iran) earthquake constrained by satellite and ground-based geodetic data, Geophysical Journal International, 169, 3, 849–865, https://doi.org/10.1111/j.1365-246X.2007.03358.x

    Ruhl, C.J., Melgar, D., Geng, J., Goldberg, D.E., Crowell, B.W., et al., 2018. A global database of strong-motion displacement GNSS recordings and an example application to PGD scaling. Seismological Research Letters, 90(1), pp.271-279

    Stein, R. S., Toda, S., 2021. Stress analysis shows slight increase in seismic hazard near Zagreb, Temblor, http://doi.org/10.32858/temblor.149

    Wiemer, S., 2001. A software package to analyze seismicity: ZMAP. Seismological Research Letters, 72(3), pp.373-382 https://doi.org/10.1785/gssrl.72.3.373

    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
    1

    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

     
  • richardmitnick 11:42 am on January 31, 2021 Permalink | Reply
    Tags: "New Report Charts Path Toward Superior Earthquake Recovery", , , Earthquake Alert system, , , , ,   

    From NIST (US): “New Report Charts Path Toward Superior Earthquake Recovery” 


    From NIST (US)

    January 27, 2021

    Jonathan Griffin
    jonathan.griffin@nist.gov
    (301) 975-4117

    1
    Credit: NigelSpiers/Shutterstock.com .

    For the last century, seismic building codes and practices have primarily focused on saving lives by reducing the likelihood of significant damage or structural collapse. Recovery of critical functions provided by buildings and infrastructure have received less attention, however. As a result, many remain vulnerable to being knocked out of service by an earthquake for months, years or for good.

    A committee of experts, formed by the National Institute of Standards and Technology (NIST) and the Federal Emergency Management Agency (FEMA) under the direction of Congress, has urged officials at all levels of government to support research and policies that could help get the buildings and services society depends on up and running quickly after an earthquake. In a report delivered to Congress, the committee outlines seven recommendations that, if acted upon, may greatly improve the resilience of communities across the nation.

    “As structural engineers we feel confident that the current building codes can deliver life safety design objectives. Now, it’s time to go beyond that and think about recovery of function,” said Siamak Sattar, a NIST structural engineer and co-author of the report.

    In 2011, a magnitude 6.3 earthquake struck Christchurch, New Zealand. Over 180 lives were lost as a result, but many more were likely saved by modern building codes. However, the city’s economy and quality of life were not spared.

    The quake damaged the city’s central business district to the point that hundreds of buildings were closed or demolished, displacing thousands of workers. Lifeline infrastructure systems — including power, clean water and roads — sustained heavy damage, further crippling the community’s ability to bounce back. In total, the estimated costs of rebuilding the city amounted to 40 billion New Zealand dollars ($26.6 billion).

    The toll taken by the Christchurch earthquake and other damaging events can in part be attributed to limitations in seismic codes and standards, as most offer little guidance on designing buildings or lifelines to recover in a timely manner in the wake of extreme events.

    To prevent major earthquakes from leaving such lasting impressions in the future, Congress entrusted NIST and FEMA — both member agencies of the National Earthquake Hazards Reduction Program (NEHRP), which NIST leads — with the responsibility of mapping a path to greater community resilience.

    Drawing expertise from both public and private sectors, NIST and FEMA assembled a committee of more than 30 engineers, architects, building owners, code officials and social scientists, including several of their own researchers, to devise options for addressing gaps in codes, standards and practices, which are described in their report to Congress.

    The first recommendation summarizes the core of the report. The authors call for members of the government, codes and standards organizations, and industry to work together in developing a national framework for setting and achieving goals based on recovery time. To produce this framework, experts must first identify what level of function provided by buildings and lifelines should be maintained after an earthquake, and then determine an acceptable time for them to be out of commission.

    “There are different metrics that we can use to help guide this framework. For example, a building may need to recover within a predefined number of days, weeks or months. If it is a hospital or emergency center then you may not want it to go down at all,” said Steve McCabe, director of NEHRP.

    The authors also highlight the need for new recovery-based design criteria for buildings and lifelines. If developed with recovery in mind, these criteria could steer design parameters — such as increasing a school’s structural strength to limit damage or designing an electrical power supply to return to service faster — toward improving community resilience. A critical phase of this process would be identifying the level of ground shaking that designs should be tailored to for recovery goals, which may vary by region.

    Other recommendations seek to help leaders meet recovery goals aligned with the first recommendation, offering guidance on implementing new design requirements for buildings and lifelines. They also provide direction for pre-disaster planning — a key step in preparing authorities to make timely decisions in the immediate aftermath of a disaster.

    The authors seek to empower communities as well by recommending the launch of an education campaign on earthquake risk and recovery, which could reach the public through social media, streaming services or other media.

    “Informed citizens are an important resource needed to develop the kind of vision required for this effort, which may well represent the largest change in building codes in 75 years,” McCabe said.

    In the report, the authors encourage officials to consider adopting functional recovery approaches that go beyond the current requirements. They assert that the initial investments of adopting new recovery-focused codes and upgrading older buildings and lifelines could likely be offset by the reduction of future losses. They also suggest that increased access to financial resources through mechanisms such as grant programs, incentive systems and public financing would help local governments scale the upfront costs.

    “The immediate aim of the report is to spark a national conversation about developing a consensus for recovery goals and timelines. This approach may eventually be reflected in building codes, but first, a considerable amount of research must be tackled,” Sattar said.

    New policies could make use of the NEHRP agencies, such as NIST and FEMA, whose expertise may enable them to provide the necessary science for sound public policy.

    The road toward this goal could take years to traverse, but it is critical.

    In the meantime, the authors encourage early action by leaders at state and local levels, as each community may have needs that national guidelines cannot fully address. Their experiences with functional recovery planning and design could also make for valuable feedback at the national level, speeding up progress toward widespread earthquake resilience that preserves quality of life in addition to life itself.

    The full report to Congress is now available online.

    See the full article here.

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    NIST Campus, Gaitherberg, MD, USA

    NIST (US) Mission, Vision, Core Competencies, and Core Values

    NIST’s mission

    To promote U.S. innovation and industrial competitiveness by advancing measurement science, standards, and technology in ways that enhance economic security and improve our quality of life.
    NIST’s vision

    NIST will be the world’s leader in creating critical measurement solutions and promoting equitable standards. Our efforts stimulate innovation, foster industrial competitiveness, and improve the quality of life.
    NIST’s core competencies

    Measurement science
    Rigorous traceability
    Development and use of standards

    NIST’s core values

    NIST is an organization with strong values, reflected both in our history and our current work. NIST leadership and staff will uphold these values to ensure a high performing environment that is safe and respectful of all.

    Perseverance: We take the long view, planning the future with scientific knowledge and imagination to ensure continued impact and relevance for our stakeholders.
    Integrity: We are ethical, honest, independent, and provide an objective perspective.
    Inclusivity: We work collaboratively to harness the diversity of people and ideas, both inside and outside of NIST, to attain the best solutions to multidisciplinary challenges.
    Excellence: We apply rigor and critical thinking to achieve world-class results and continuous improvement in everything we do.

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