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  • richardmitnick 8:06 am on February 7, 2018 Permalink | Reply
    Tags: Buildings collapse in coastal Taiwan M=6.4 quake, , , , temblor   

    From temblor: “Buildings collapse in coastal Taiwan M=6.4 quake” 

    1

    temblor

    February 6, 2018
    David Jacobson

    1
    This picture shows the 270 Marshal Hotel, whose lower floors collapsed in today’s M=6.4 earthquake. (Photo from: KULAS_TW)

    A second large earthquake in 2 days strikes Eastern Taiwan

    Just before midnight local time, a M=6.4 earthquake struck Eastern Taiwan, toppling buildings, collapsing ground floors, and buckling streets. The quake, which comes just two days after a M=6.1 approximately 20 km to the southeast, occurred at a depth of 10 km and registered very strong shaking in the city of Hualien according to the Taiwan Central Weather Bureau. Hualien is home to over 100,000 people. Yesterday, when we wrote about the M=6.1 over the weekend, we pointed out that its location marks the intersection of the Longitudinal Valley Fault and the Ryukyu Trench. Because of this, the area is prone to experiencing large magnitude earthquakes, meaning this quake should not be considered surprising. Further, earthquakes at fault junctions and tips are slightly more likely to trigger still larger shocks than others.

    2
    This Google Earth image shows the location of today’s M=6.4 earthquake near the city of Hualien, which is home to over 100,000 people.

    3
    This picture shows a partially-collapsed building in the city of Hualien, on Taiwan’s eastern coast. The earthquake which caused this damage was a M=6.4 quake which struck just two days after a M=6.1 just 15 km to the southeast.

    4
    This picture from The Guardian shows a building which suffered at least a first story collapse in today’s M=6.4 earthquake north of Taiwan’s city of Hualien.

    Based on early reports and pictures, there is significant damage in Hualien, at least two people are confirmed to have been killed, and over 200 people were injured, 27 of them seriously according to the New York Times. Additionally, NPR announced that seven buildings had collapsed and while people remain trapped beneath the collapsed buildings, the National Fire Agency announced that they had rescued 149 people trapped in the rubble. However, people remain trapped in a partially-collapsed hotel. The photos above show some of the major damage sustained in the earthquake.

    The reported damage is higher than forecast by the USGS PAGER system, which anticipated less than $1 million in damage. This is likely due to an underestimation of the amount of shaking around Hualien. The ShakeMap produced by Taiwan’s Central Weather Bureau can be seen below.

    5
    This figure shows the ShakeMap produced by Taiwan’s Central Weather Bureau. In the city of Hualien, shaking reached Intensity Level 7.

    A yet-larger earthquake could still occur

    6
    This Temblor map shows the location of the recent earthquake on Taiwan’s eastern coast. Both of the recent M=6+ quakes occurred at the northern tip of the Longitudinal Valley Fault, Taiwan’s longest and most active fault.

    While the earthquake over the weekend was predominantly compressional in nature, today’s event was nearly pure strike-slip, according to both the USGS and GFZ-Potsdam. Because of this, today’s quake may have struck at the northern tip of the Longitudinal Valley Fault, which is known to have both compressional and left-lateral motion. As we said yesterday, 30% of all earthquakes in Taiwan occur on or near this fault. It also has the highest slip rate of all faults in Taiwan.

    Domino Theory?

    While the M=6.4 shock occurred offshore at the northern tip of the Longitudinal Valley Fault, several of its large aftershocks occurred 20 km (12 miles) to the south, beneath Hualien, also on or near the Longitudinal Valley Fault. So, there appears to be a seismic propagation of aftershocks along the Longitudinal Valley Fault. This raises concerns that these events themselves could be foreshocks to still larger earthquakes that could rupture south along Taiwan’s longest, and most active fault.

    Today’s shock should not come as a surprise. The Taiwan Earthquake Model, a university, government, and industry consortium that uses the tools and libraries of the Global Earthquake Model (GEM Foundation), is shown below. The area around the recent earthquakes has one of the highest hazards in the entire country. Therefore, residents of Eastern Taiwan should be prepared for potentially larger, more damaging earthquakes, perhaps propagating to the south.

    7
    This figure shows the Taiwan Earthquake Model. What is evident in this figure is that the location of today’s earthquake is in a location of extremely high hazard. (Figure from Cheng et al)

    References [sorry, no links]
    Taiwan’s Central Weather Bureau
    EMSC
    Taiwan Earthquake Model from, Thomas (Chin-Tung) Cheng et al., Disaster Prevention Technology Research Center, Sinotech Engineering Consultants, Inc. – Link
    Kate Huihsuan Chen, Shinji Toda, and Ruey-Juin Rau, A leaping, triggered sequence along a segmented fault: The 1951 ML 7.3 Hualien-Taitung earthquake sequence in eastern Taiwan, JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 113, B02304, doi:10.1029/2007JB005048, 2008
    USGS
    BBC
    New York Times
    The Guardian
    NPR

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    You can help many citizen scientists in detecting earthquakes and getting the data to emergency services people in affected area.
    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).

    BOINCLarge

    BOINC WallPaper

    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

    Earthquake country is beautiful and enticing

    Almost everything we love about areas like the San Francisco bay area, the California Southland, Salt Lake City against the Wasatch range, Seattle on Puget Sound, and Portland, is brought to us by the faults. The faults have sculpted the ridges and valleys, and down-dropped the bays, and lifted the mountains which draw us to these western U.S. cities. So, we enjoy the fruits of the faults every day. That means we must learn to live with their occasional spoils: large but infrequent earthquakes. Becoming quake resilient is a small price to pay for living in such a great part of the world, and it is achievable at modest cost.

    A personal solution to a global problem

    Half of the world’s population lives near active faults, but most of us are unaware of this. You can learn if you are at risk and protect your home, land, and family.

    Temblor enables everyone in the continental United States, and many parts of the world, to learn their seismic, landslide, tsunami, and flood hazard. We help you determine the best way to reduce the risk to your home with proactive solutions.

    Earthquake maps, soil liquefaction, landslide zones, cost of earthquake damage

    In our iPhone and Android and web app, Temblor estimates the likelihood of seismic shaking and home damage. We show how the damage and its costs can be decreased by buying or renting a seismically safe home or retrofitting an older home.

    Please share Temblor with your friends and family to help them, and everyone, live well in earthquake country.

    Temblor is free and ad-free, and is a 2017 recipient of a highly competitive Small Business Innovation Research (‘SBIR’) grant from the U.S. National Science Foundation.

    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

    Advertisements
     
  • richardmitnick 9:58 pm on January 26, 2018 Permalink | Reply
    Tags: , , , , temblor   

    From temblor: “M=4 Southern California earthquake highlights Elsinore Fault’s destructive potential” 

    1

    temblor

    January 25, 2018
    David Jacobson

    1
    This morning’s M=4 earthquake in Southern California struck just northwest of Lake Elsinore.

    Last night, at 2:09 a.m. a M=4 earthquake struck Southern California approximately 25 km southwest of Riverside. The quake occurred at a depth of 11 km, and was felt widely across the region, registering over 11,000 felt reports on the USGS website. Based on the focal mechanism produced by the USGS, this quake was primarily compressional in nature, with some strike-slip motion, and close to the Elsinore Fault. Earthquakes with this focal mechanism are not uncommon here. However, this event did not occur on the main strand of the Elsinore Fault, but rather a small secondary fault. Because of the relatively small magnitude of this earthquake, no damage has been reported or is expected. However, it did wake tens of thousands of people in Southern California. Additionally, Dr. Craig Nicholson, Research Geophysicist at the Marine Science Institute of U.C. Santa Barbara, told Temblor, “There has been a persistent cluster of ‘off-fault’ earthquakes in this area for quite some time. The Elsinore fault is certainly multi-stranded, but here there has been sustained seismicity west of the fault zone and west of the southern end of the Whittier fault. These earthquakes could be related to low-angle blind faults similar to the Peralta Hills fault located farther north.”

    2
    This Temblor map shows the location of this morning’s earthquake southwest of San Bernardino. Also highlighted in this map are the three major faults in Southern California. This quake registered over 11,000 felt reports on the USGS website.

    Even though this earthquake did not occur on the main strand of the Elsinore Fault, because of its proximity, it does give us a chance to highlight one of Southern California’s largest faults. Just by itself, and not including its northern and southern extensions, the Elsinore Fault extends for approximately 180 km through Southern California. However, despite its size, it is one of the quietest faults in the region. Most recently, it ruptured in 1910 in a M=6 earthquake. That event was not particularly damaging though, it did topple some chimneys in nearby communities. Other than that earthquake, there are no major historic quakes along the Elsinore Fault.

    The Elsinore Fault: A sleeping giant

    Just because a large earthquake has not happened historically does not mean a damaging event could not occur. In the USGS scenario catalog, they show that should the Elsinore rupture from end to end, a M=7.8 could be generated. Such an event would be devastating for the region and could cause damage from San Diego to Los Angeles.

    While a M=7.8 earthquake may not be the most likely scenario, by using the Global Earthquake Acitivity Rate (GEAR) model, we can see what is likely in your lifetime. This model uses global strain rates and the last 40 years of seismicity to estimate the likely earthquake magnitude in your lifetime anywhere on earth. From the figure below, one can see that in the location of this morning’s event, a M=6.5+ is likely. While such an event would not have as large an impact on all of Southern California, it could be devastating to places like Riverside and Mission Viejo.

    3
    This Temblor map shows the Global Earthquake Activity Rate (GEAR) model for Southern California. This model uses global strain rates and the last 40 years of seismicity to forecast the likely earthquake magnitude in your lifetime. This figure highlights how in the location of this morning’s earthquake, a M=6.5+ is likely in your lifetime.

    References [Sorry, no links.]
    USGS
    Southern California Earthquake Data Center
    LA Times
    Hull, Alan and Nicholson, Craig, Seismotectonics of the Northern Elsinore fault zone, Southern California, Bulletin of the Seismological Society of America 82(2) · January 1992

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    You can help many citizen scientists in detecting earthquakes and getting the data to emergency services people in affected area.
    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).

    BOINCLarge

    BOINC WallPaper

    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

    Earthquake country is beautiful and enticing

    Almost everything we love about areas like the San Francisco bay area, the California Southland, Salt Lake City against the Wasatch range, Seattle on Puget Sound, and Portland, is brought to us by the faults. The faults have sculpted the ridges and valleys, and down-dropped the bays, and lifted the mountains which draw us to these western U.S. cities. So, we enjoy the fruits of the faults every day. That means we must learn to live with their occasional spoils: large but infrequent earthquakes. Becoming quake resilient is a small price to pay for living in such a great part of the world, and it is achievable at modest cost.

    A personal solution to a global problem

    Half of the world’s population lives near active faults, but most of us are unaware of this. You can learn if you are at risk and protect your home, land, and family.

    Temblor enables everyone in the continental United States, and many parts of the world, to learn their seismic, landslide, tsunami, and flood hazard. We help you determine the best way to reduce the risk to your home with proactive solutions.

    Earthquake maps, soil liquefaction, landslide zones, cost of earthquake damage

    In our iPhone and Android and web app, Temblor estimates the likelihood of seismic shaking and home damage. We show how the damage and its costs can be decreased by buying or renting a seismically safe home or retrofitting an older home.

    Please share Temblor with your friends and family to help them, and everyone, live well in earthquake country.

    Temblor is free and ad-free, and is a 2017 recipient of a highly competitive Small Business Innovation Research (‘SBIR’) grant from the U.S. National Science Foundation.

    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 9:06 am on January 24, 2018 Permalink | Reply
    Tags: , Mt. Kusatsu-Shirane, , , temblor,   

    From temblor: “Volcanic eruption outside Tokyo kills one, injures a dozen” 

    1

    temblor

    January 23, 2018
    David Jacobson

    1
    Today’s eruption at Mt. Kusatsu-Shirane killed one and injured at least a dozen. (Photo from zoomingjapan.com)

    Today, a volcano approximately 150 km (93 miles) northwest of Tokyo erupted, leaving one dead and injuring at least 12. The volcano, Mt. Kusatsu-Shiranesan, is located near a popular ski resort, and the people injured were skiing on the slopes and hit by flying rocks. The one fatality was a soldier in a group of 30 that were undergoing ski training. As reported by the BBC, at least 76 people are seeking shelter in a mountaintop rest home. In addition to this eruption, an avalanche, believed to have been caused by the eruption, was triggered.


    The video above shows the time the eruption occurred. Towards the end of the video, you will see black ash on the right hand side and small volcanic bombs (rocks) fly across the screen.

    This eruption at Mt. Kusatsu-Shiranesan came without warning, which is why dozens of people were within a km of the erupting vent. So, far, volcanic debris have not been found more than about a km away. Because, of this, the impact of the eruption is primarily on the ski resort and not on the town of Kusatsu, 5 km (3 mi) away. As a result of this eruption, the Japan Meteorological Agency has advised people to stay away from the volcano, and many people have already been evacuated.

    2
    The eruption at Mt. Kusatsu-Shiranesan left the slopes at a popular ski resort black with ash. (Photo from: Suo Takekuma/Kyodo News)

    While this eruption was relatively small, it appears to be typical of eruptions in the last 80 years at Mt. Kusatsu-Shiranesan. Most recently, the volcano erupted in 1983 in what could be described as a mildly explosive event. Additionally, because there is a crater lake at the summit, many past eruptions have been phreatic in nature. Phreatic eruptions are steam-driven and are caused when water is heated extremely rapidly, which can cause it to flash to steam, which can generate small explosions. It is unclear if this was the cause of today’s event. Should any new information come in, we will update this post.

    References [sorry, no links.]
    Smithsonian Institute, National Museum of Natural History, Global Volcanism Program
    BBC
    Time
    Japan Meteorological Agency (JMA)

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    You can help many citizen scientists in detecting earthquakes and getting the data to emergency services people in affected area.
    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).

    BOINCLarge

    BOINC WallPaper

    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

    Earthquake country is beautiful and enticing

    Almost everything we love about areas like the San Francisco bay area, the California Southland, Salt Lake City against the Wasatch range, Seattle on Puget Sound, and Portland, is brought to us by the faults. The faults have sculpted the ridges and valleys, and down-dropped the bays, and lifted the mountains which draw us to these western U.S. cities. So, we enjoy the fruits of the faults every day. That means we must learn to live with their occasional spoils: large but infrequent earthquakes. Becoming quake resilient is a small price to pay for living in such a great part of the world, and it is achievable at modest cost.

    A personal solution to a global problem

    Half of the world’s population lives near active faults, but most of us are unaware of this. You can learn if you are at risk and protect your home, land, and family.

    Temblor enables everyone in the continental United States, and many parts of the world, to learn their seismic, landslide, tsunami, and flood hazard. We help you determine the best way to reduce the risk to your home with proactive solutions.

    Earthquake maps, soil liquefaction, landslide zones, cost of earthquake damage

    In our iPhone and Android and web app, Temblor estimates the likelihood of seismic shaking and home damage. We show how the damage and its costs can be decreased by buying or renting a seismically safe home or retrofitting an older home.

    Please share Temblor with your friends and family to help them, and everyone, live well in earthquake country.

    Temblor is free and ad-free, and is a 2017 recipient of a highly competitive Small Business Innovation Research (‘SBIR’) grant from the U.S. National Science Foundation.

    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 10:04 am on January 12, 2018 Permalink | Reply
    Tags: , , , Series of earthquakes strikes Iran-Iraq border, , temblor   

    From temblor: “Series of earthquakes strikes Iran-Iraq border” 

    1

    temblor

    January 11, 2018
    David Jacobson
    Manuel Berberian

    1
    The city of Baghdad felt shaking from today’s series of earthquakes along the Iran-Iraq border.

    This morning, ten M=4.0+ earthquakes struck the Iran-Iraq border. The largest of these, a M=5.5 near the Iraqi city of Mandali, was also widely felt in Baghdad. Because the area around the epicenter is sparsely-populated, there are no reports of major damage, though five people were injured. However, some more minor damage has been seen close to the epicenter (see below). These earthquakes come less than two months after a M=7.3 quake struck less than 150 km to the north. That earthquake killed over 500 and destroyed numerous buildings.

    2
    This Google Earth image shows USGS locations of the series of earthquakes to strike the Iran-Iraq border this morning.

    Based on the USGS focal mechanism, this morning’s earthquakes were compressional in nature. This compression is due to the collision of the Arabian and Eurasian plates at a rate of approximately 24 mm/yr. This collision is also responsible for the formation of the Zagros Mountains, which extend through both Iran and Iraq. Today’s quake struck along the southern edge of the Zagros Mountains.

    3
    Damage caused by thing morning’s earthquakes along the Iran-Iraq border.

    At this stage, it is not clear whether these earthquakes are remote aftershocks of the M=7.3 in November, or isolated events. Nonetheless, that have brought further shaking to the border region. This area was last strongly shaking when a M=6.1 earthquake in 1967 hit the area.

    From the Global Earthquake Activity Rate (GEAR) model, which is available in Temblor, we can see if these earthquakes should be considered surprising or not. This model uses global strain rates and the last 40 years of seismicity to forecast what the likely earthquake magnitude is in your lifetime anywhere on earth. In the figure below, one can see that around this morning’s earthquake, a M=5.5+ is likely in your lifetime. Therefore, these quakes, while a reminder of the region’s seismic hazard, should not be considered surprising.

    4
    This Temblor map shows the Global Earthquake Activity Rate (GEAR) model for much of Iran and Iraq. This shows how today’s earthquakes should not be considered surprising, as M=5.5+ quakes are likely in your lifetime.

    Reference
    USGS

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    You can help many citizen scientists in detecting earthquakes and getting the data to emergency services people in affected area.
    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).

    BOINCLarge

    BOINC WallPaper

    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

    Earthquake country is beautiful and enticing

    Almost everything we love about areas like the San Francisco bay area, the California Southland, Salt Lake City against the Wasatch range, Seattle on Puget Sound, and Portland, is brought to us by the faults. The faults have sculpted the ridges and valleys, and down-dropped the bays, and lifted the mountains which draw us to these western U.S. cities. So, we enjoy the fruits of the faults every day. That means we must learn to live with their occasional spoils: large but infrequent earthquakes. Becoming quake resilient is a small price to pay for living in such a great part of the world, and it is achievable at modest cost.

    A personal solution to a global problem

    Half of the world’s population lives near active faults, but most of us are unaware of this. You can learn if you are at risk and protect your home, land, and family.

    Temblor enables everyone in the continental United States, and many parts of the world, to learn their seismic, landslide, tsunami, and flood hazard. We help you determine the best way to reduce the risk to your home with proactive solutions.

    Earthquake maps, soil liquefaction, landslide zones, cost of earthquake damage

    In our iPhone and Android and web app, Temblor estimates the likelihood of seismic shaking and home damage. We show how the damage and its costs can be decreased by buying or renting a seismically safe home or retrofitting an older home.

    Please share Temblor with your friends and family to help them, and everyone, live well in earthquake country.

    Temblor is free and ad-free, and is a 2017 recipient of a highly competitive Small Business Innovation Research (‘SBIR’) grant from the U.S. National Science Foundation.

    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 5:25 pm on January 4, 2018 Permalink | Reply
    Tags: , Largest Hayward Fault earthquake since 1981 raises questions about what could happen next, , , temblor   

    From temblor: “Largest Hayward Fault earthquake since 1981 raises questions about what could happen next” 

    1

    temblor

    January 4, 2018
    David Jacobson
    Ross Stein

    1
    Last night’s M=4.4 earthquake beneath Berkeley was felt by approximately 10 million people across the entire Bay Area. The quake struck along the Hayward Fault, which has a 29% of rupturing in a large magnitude earthquake in the next 30 years.

    The entire Bay Area was awakened

    Last night, at 2:39 a.m. local time, a M=4.4 earthquake struck along the Hayward Fault underneath the city of Berkeley. The quake was felt throughout the entire Bay Area, and by noon today, over 35,000 people had filled out felt reports on the USGS website. Based on the distribution of shaking, nearly 10 million people would have been exposed to some level of shaking. Close to the epicenter shaking was moderate, and no damage is expected. Based on its magnitude, the quake was felt across a much greater area than expected.

    The last M=4.4 shock on or close to the Hayward Fault struck near Fremont in 1981, some 36 years ago. A M=4.5 shock struck on the Rodgers Creek Fault in 2006 near Santa Rosa. The Rodgers Creek Fault is effectively the same Fault with a different name.

    2
    This Temblor map shows the location of last night’s M=4.4 earthquake beneath Berkeley. Despite its moderate magnitude, shaking was felt over the entire Bay Area.

    The Hayward Fault—149 years and counting since the last large event

    Based on the location, depth (13 km or 8 mi), and mechanism (right-lateral strike-slip), this earthquake very likely occurred on the Hayward Fault itself, and not a secondary strand. The Hayward Fault extends from San Pablo Bay where it joins up with the Rodgers Creek Fault, to south of San Jose, where it merges with the Calaveras Fault, a length of 140 mi (230 km). It makes up one of the larger faults within the San Andreas Fault System, and has a history of large, damaging earthquakes. In 1868, a M~6.8 earthquake destroyed downtown Hayward, and did significant damage in San Francisco. In fact, the 1868 earthquake was known as the “Great Earthquake” until 1906.

    3
    This figure shows LiDAR topographic imagery of the Hayward Fault, as well as the location of this morning’s earthquake. This quake struck in an area where fault creep observed. However, at the depth at which this quake occurred (13 km or 8 mi), the fault is believed to be locked.

    The Hayward Fault creeps, as does a 100-mi (170-km) long section of the San Andreas, and only a handful of other California faults. This means that the Hayward Fault is not frictionally locked and can slip without large earthquakes. While some creeping faults are completely unlocked and do not build up the significant stress needed to generate large earthquakes, the Hayward Fault is only partially locked. So while there is creep at the ground surface, large (M~7) earthquakes tend to occur on average every 161±65 years. For those keeping track, it has been 149 years since the last major event.

    4
    This picture from the New Yorker shows evidence of creep along the Hayward Fault. Because the fault is not completely locked, there is movement in the absence of earthquakes. Evidence such as this is visible throughout the East Bay in sidewalks, buildings, and roads.

    Today’s quake struck on the edge of a large stuck patch of the Hayward Fault

    In the area around this morning’s earthquake, there is significant evidence of creep. The figure below, from Shirzaei and Burgmann, 2013, shows creep along the Hayward Fault, with the approximate location of today’s earthquake shown. What becomes evident from this figure is that the area in which this morning’s earthquake nucleated is a locked portion of the fault, and that locked patch extends for 20-30 km (12-20 mi) to the southeast.

    Prof. Manoochehr Shirzaei at Arizona State University told Temblor that today’s event “occurred in an area that is stressed due to creep on the surrounding segments, and so was encouraged.” USGS geologist David Schwartz added that, “the M=4.4 occurred along a ‘hotspot’ on the Hayward fault. This is an approximately 8 km (5 mi) long section of the fault that has hosted 15 M 3.0-4.0 shocks in the past 10 years. [Today’s earthquake is] the largest and deepest event in this grouping but its location not unusual.” Because of all of this, this earthquake should not be considered surprising.

    5
    This figure, courtesy of Professor Manoochehr Shirzaei at Arizona State University shows the amount of creep along the Hayward Fault in addition to the location of notable earthquakes. This highlights how the area is a “hotspot” and that this morning’s event should not be considered surprising. As Prof. Shirzaei also points out, aseismic slip surrounding the location of this morning’s quake could contribute to the activity.

    What next?

    Based on the lack of creep in the location of today’s event, as well as the large locked patch to the south toward Fremont and Hayward, if a large earthquake were to start here, we believe it would rupture to the south. This area also has a slip deficit of more than a meter (3.3 ft) since 1868, as shown in the figure below, suggesting it could be more susceptible to a large earthquake.

    6
    This Figure from Shirzaei and Burgmann, 2013 shows the slip deficit along the Hayward Fault since the last major earthquake in 1868. This highlights how the area in which today’s earthquake occurred is within a section of fault where there is a significant slip deficit, suggesting that if a major quake were to occur it would likely rupture to the south (to the right in the figure).

    Nevertheless, the statistical likelihood of this morning’s earthquake being a foreshock to a M=6+ event in the next week is low, about 1 chance in 250, according to the USGS. However, the USGS does also estimate that there is a 10% chance that this could be a foreshock to an earthquake of equal or greater magnitude. Therefore, people should renew and reconsider their seismic readiness.

    One of the reasons why the Hayward Fault is of great importance is because James Lienkaemper and Patrick Williams, 2010 calculated from the record they unearthed of prehistoric earthquakes that there is a 29% chance of a large quake along this portion of the Hayward Fault. The USGS has multiple earthquake scenarios for this section of fault, some of which reach M=7.4. Such an event would have a significant impact on the entire Bay Area, stressing the importance of preparation. The USGS is developing a scenario of such an event (HayWired)

    We are behaving like cigarette smokers

    David Oppenheimer, the former director of the USGS Northern California Seismic Network, had this to say to Temblor: “The scientific and engineering communities have led us to the solution to seismic resilience, but the public behaves like a cigarette smoker. They know that quakes are bad for them, but they are not willing to do what they should.”

    He continues, “The solution is to follow the leads of San Francisco, Santa Monica and Los Angeles that require substandard residential structures to be identified and seismically retrofit in a timely fashion. Unfortunately, none of these programs apply to homes; they only address apartment and larger buildings. Mortgage lenders should require property owners to carry earthquake insurance. Elected officials must do their part to implement ordinances and laws that require the public to upgrade at-risk private property. A small investment in mitigation will have large payoffs to property owners, inhabitants, and resiliency of our metropolitan area.”

    References

    Manoochehr Shirzaei, Roland Bürgmann, Taka’aki Taira (2013), Implications of recent asperity failures and aseismic creep for time-dependent earthquake hazard on the Hayward fault, Earth and Planetary Science Letters 371–372 (2013) 59–66, doi.org/10.1016/j.epsl.2013.04.024

    Shirzaei, M., and R. Burgmann (2013), Time-dependent model of creep on the Hayward fault from joint
    inversion of 18 years of InSAR and surface creep data, J. Geophys. Res. Solid Earth, 118, doi:10.1002/jgrb.50149.

    James J. Lienkaemper, Patrick L. Williams, and Thomas P. Guilderson, Evidence for a Twelfth Large Earthquake on the Southern Hayward Fault in the Past 1900 Years, Bulletin of the Seismological Society of America, Vol. 100, No. 5A, pp. 2024–2034, October 2010, doi: 10.1785/0120090129

    Detweiler, S.T., and Wein, A.M., eds., 2017, The HayWired earthquake scenario—Earthquake hazards: U.S. GeologicalSurvey Scientific Investigations Report 2017–5013–A–H, 126 p., https://doi.org/10.3133/sir20175013v1.

    USGS

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    You can help many citizen scientists in detecting earthquakes and getting the data to emergency services people in affected area.
    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).

    BOINCLarge

    BOINC WallPaper

    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

    Earthquake country is beautiful and enticing

    Almost everything we love about areas like the San Francisco bay area, the California Southland, Salt Lake City against the Wasatch range, Seattle on Puget Sound, and Portland, is brought to us by the faults. The faults have sculpted the ridges and valleys, and down-dropped the bays, and lifted the mountains which draw us to these western U.S. cities. So, we enjoy the fruits of the faults every day. That means we must learn to live with their occasional spoils: large but infrequent earthquakes. Becoming quake resilient is a small price to pay for living in such a great part of the world, and it is achievable at modest cost.

    A personal solution to a global problem

    Half of the world’s population lives near active faults, but most of us are unaware of this. You can learn if you are at risk and protect your home, land, and family.

    Temblor enables everyone in the continental United States, and many parts of the world, to learn their seismic, landslide, tsunami, and flood hazard. We help you determine the best way to reduce the risk to your home with proactive solutions.

    Earthquake maps, soil liquefaction, landslide zones, cost of earthquake damage

    In our iPhone and Android and web app, Temblor estimates the likelihood of seismic shaking and home damage. We show how the damage and its costs can be decreased by buying or renting a seismically safe home or retrofitting an older home.

    Please share Temblor with your friends and family to help them, and everyone, live well in earthquake country.

    Temblor is free and ad-free, and is a 2017 recipient of a highly competitive Small Business Innovation Research (‘SBIR’) grant from the U.S. National Science Foundation.

    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 5:19 pm on December 29, 2017 Permalink | Reply
    Tags: A Challenge by Yue et al, Dispute: Do Magnitude 7-8 mainshocks commonly trigger immediate damaging aftershocks up to 300 km (180 mi) away?, Dueling posters at the Fall Meeting of the American Geophysical Union, , How could these large aftershocks have been overlooked?, Implications of the Fan-Shearer hypothesis, Singing seismograms, So who is right?, temblor   

    From temblor: “Dispute: Do Magnitude 7-8 mainshocks commonly trigger immediate damaging aftershocks up to 300 km (180 mi) away?” 

    1

    temblor

    December 29, 2017
    Ross Stein, Ph.D, Temblor

    1
    By analyzing a series of great earthquakes off the coast of Sumatra, Yue et al. argue that the seismic signals interpreted by Fan and Shearer as aftershocks are actually water reverberations in near-shore regions. (Photo from: trekkersblog.com)

    In September 2016, Wenyuan Fan and Peter Shearer, from the Scripps Institution of Oceanography at U.C. San Diego, published an astonishing discovery in Science. Fan and Shearer detected nearly 50 previously unidentified M≥5.5 aftershocks up to 300 kilometers (200 mi) away from their M=7-8 mainshocks during the brief passage of the seismic ‘surface’ waves from the mainshock, or within 3 minutes. The authors concluded that remote dynamic triggering commonly exists and fundamentally promotes aftershock occurrence throughout the globe.

    1
    This is an annotated version of Fig. 2b of Fan and Shearer (2016), for the case of a 2013 mainshock off the Japan coast. The contours give location uncertainties of the mainshock(magenta) and aftershock (turquoise). The aftershock locates between the trench and the coast, where the seafloor begins to shallow. Virtually all the discovered aftershocks occur between oceanic trenches and the coast.

    How could these large aftershocks have been overlooked?

    There are no large, immediate, and remote aftershocks in any seismic catalog, and so most of us had concluded that this must be exceedingly rare, or is non-existent. That’s because today, any M≥4.5 shock anywhere on Earth can be reliably detected.

    But, during the first few minutes after a large mainshock, its seismic wave train could obscure aftershocks, and so during this period, large shocks could conceivably have been hidden. To overcome this obstacle, Fan and Shearer used a technique in which a continent’s worth of seismometers are retroactively trained on the site of a single large earthquake halfway around the globe, and then used to track where the seismic energy was released in time. The method, called ‘beam back-projection,’ was introduced by Miaki Ishii, Peter Shearer, Heidi Houston and John Vidale in 2005 (Ishii et al., 2005). Although remote dynamic triggering of tiny aftershocks is well known (Velasco et al., 2008; Parsons et al., 2014), there are only a few examples of M≥5.5 aftershocks (Johnson et al., 2015), the most impressive of which was the 2012 M=8.6 Indian Ocean shock, which triggered large aftershocks all over the globe (Pollitz et al., 2012). But those aftershocks struck over several days—not minutes—long after the seismic waves had vanished.

    Implications of the Fan-Shearer hypothesis

    If they are correct, the hazard after a large mainshock would be more widespread than understood today, and the first several minutes after a large mainshock are more dangerous than we currently assume. But there is another, equally important, implication: For historical quakes, whose magnitudes and locations are interpreted from contemporary intensity reports (descriptions of shaking), we might be overestimating their magnitudes and blurring their locations, because widespread shaking in aftershocks would be misconstrued as caused by the mainshock.

    A Challenge by Yue et al.

    In October 2017, Han Yue, from Beijing University, Jorge C. Castellanos, Chunquan Yu, and Lingsen Meng from UCLA and Zhongwen Zhan from Caltech published a rebuttal of the Fan-Shearer hypothesis in Geophysical Research Letters. In a nutshell, Yue et al. argue that the seismic signals interpreted by Fan and Shearer as aftershocks are actually water reverberations in near-shore regions. The reverberations are triggered by the seismic waves launched by the mainshock. Fan and Shearer had raised this possibility in their paper, but ultimately dismissed it. Yue et al. present a series of falsification tests, but I am going to focus on what I consider the two most persuasive.

    3
    This is a simplified and annotated version of Fig. 3 of Yue et al. (2017). P waves transmit through rock and water, but S waves only through rock. So, if the energy pulses northeast (landward) of the trench were indeed aftershocks, they should appear in both panels, but they do not. ‘Seismic energy’ is the beam back-projection amplitude. The ‘+’ signs refer to the pulses in time shown in the figure below.

    In the figure above, energy from a M=7.2 mainshock southwest of the trench is imaged by P waves. The energy is spread over about 100 km because this is roughly the rupture area of the shock. There are also strong energy pulses landward of the trench, near the ‘10 s resonance contour.’ These are the pulses identified by Fan and Shearer as aftershocks. But Yue et al. point out that if these were aftershocks, they should also appear when using S waves. But they are absent in the right-hand panel above. If, instead, they were water reverberations, they should appear in the P wave panel but not in the S wave panel, because S waves do not transmit in water. So, this would seem to be a very strong test, which the Fan-Shearer hypothesis does not pass.

    Singing seismograms

    In a second falsification test, Yue et al lined up seismograms of the M=7.2 mainshock recorded throughout the hemisphere. It takes about 25 s for a M=7.2 earthquake to rupture, and in those first 20-30 seconds, one sees the somewhat chaotic signature of the rupture. But beginning at 61 s (and perhaps at 51 s) one can see a coherent pulse on all the records (the red ‘+’ signs in the figure below). This pattern repeats at least three times at 10 s intervals (green, blue, and cyan ‘+’ signs in the figure below).

    4
    This is a simplified and annotated version of Yue et al. Fig. 2. Seismograms from throughout the hemisphere show coherent reverberations every 10 s. This becomes evident 61 s after the mainshock, and lasts at least until 92 s. This rhythmic ringing is unlikely to be caused by an earthquake, whose oscillations would normally be much more irregular. Yue et al. located the source of the ringing; those ‘+’ icons are shown in the preceding figure.

    Yue et al argue that earthquakes do not produce such simple and periodic pulses. When Yue et al. located the source of the pulses, they land next to the beam back-projection energy pulses that Fan and Shearer identified as aftershocks. In addition, the pulses are very close to the seafloor depth contour that would produce the observed 10 s resonance. So, it would be hard to argue that water reverberation was not occurring, and occurring right where Fan and Shearer identified aftershocks.

    Dueling posters at the Fall Meeting of the American Geophysical Union

    Fortunately, Wenyuan Fan (now a Post-Doctoral Scholar at Woods Hole Oceanographic Institution) and Han Yue presented side-by-side posters at AGU Meeting in New Orleans two weeks ago. This gave everyone the chance to see both sides of the story, and it also enabled me to pose questions to each author based on the arguments and rebuttals of the other.

    Fan and Shearer believe that with more tuning, an aftershock energy pulse might emerge in the S wave analysis. They now concede that water reverberations are evident in the signals, but they argue that these are water reverberations from the remote aftershock, not the mainshock. So, while remote dynamic aftershocks might be less common than they originally proposed, it still occurs. Han Yue says that he cannot (yet) eliminate this possibility, and so the debate continues.

    So, who’s right?

    In addition to the falsification tests, two other factors lead me to believe that Yue et al. are likely correct, and that few if any of the signals are actually aftershocks. Why would different types of mainshocks (thrust, extensional, and strike-slip) all trigger aftershocks at about the same water depth between the trench and the coast? This just seems very unlikely. Beyond that, if there is a simpler, quotidian explanation for a phenomenon (water reverberation), then it should be favored over a more exotic interpretation (heretofore unseen aftershocks).

    With that said, debates like this are essential to science, which only advances when bold new ideas are promulgated, and promulgated in a manner that can be unambiguously tested. And for that we can thank Fan and Shearer. All we can really do in science is falsify hypotheses; proving something right is extremely difficult.

    Here is a video of seismic wave propagation through rock and water by Yue et al., 2017

    The first ring-like wave launched from the 20-km deep hypocenter is the P wave, traveling at about 7 km/sec; the second is S wave, traveling at about half that speed. The video is moving at about realtime. The thick black line is the seafloor. At the site of the epicenter, the seafloor is about 5 km (3 mi) deep. The camera moves with the advancing waves toward the coast. Water reverberations become most pronounced when the seafloor shallows to about 2 km deep, at a distance of about 220 km. The P waves bounce back and forth every 10 s or so in the water.

    References
    [Unfortunately the writer does not simply give us the links, but you can retrieve them with the references that they do give.]

    Wenyuan Fan and Peter M. Shearer (2016), Local near instantaneously dynamically triggered aftershocks of large earthquakes, Science, 353, 1133-1136, DOI: 10.1126/science.aag0013.

    Miaki Ishii, Peter M. Shearer, Heidi Houston, and John E. Vidale, Extent, duration and speed of the 2004 Sumatra-Andaman earthquake imaged by the HI-Net array (2005), Nature, DOI: 10.1038/nature03675.

    Christopher W. Johnson, R. Bürgmann, and F. F. Pollitz (2015), Rare dynamic triggering of remote M≥ 5.5 earthquakes from global catalog analysis, J. Geophys. Res., 120, 1748–1761, doi:10.1002/ 2014JB011788.

    Tom Parsons, Margaret Segou, Warner Marzocchi (2014), The global aftershock zone, Tectonophysics, 618, 1–34, .doi.org/10.1016/j.tecto.2014.01.038

    Fred F. Pollitz, Ross S. Stein, Volkan Sevilgen, and Roland Bürgmann (2012), The 11 April 2012 east Indian Ocean earthquake triggered large aftershocks worldwide, Nature, 490, 250–253, DOI:10.1038/nature11504.

    Aaron A. Velasco, S. Hernandez, T. Parsons, and K. Pankow (2008), Global ubiquity of dynamic earthquake triggering, Nature Geoscience, 1, 375–379, doi:10.1038/ngeo204

    Han Yue, Jorge C. Castellanos, Chunquan Yu, Lingsen Meng, and Zhongwen Zhan (2017), Localized water reverberation phases and its impact on backprojection images, Geophys. Res. Letts., DOI: 10.1002/2017GL073254.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    You can help many citizen scientists in detecting earthquakes and getting the data to emergency services people in affected area.
    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).

    BOINCLarge

    BOINC WallPaper

    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

    Earthquake country is beautiful and enticing

    Almost everything we love about areas like the San Francisco bay area, the California Southland, Salt Lake City against the Wasatch range, Seattle on Puget Sound, and Portland, is brought to us by the faults. The faults have sculpted the ridges and valleys, and down-dropped the bays, and lifted the mountains which draw us to these western U.S. cities. So, we enjoy the fruits of the faults every day. That means we must learn to live with their occasional spoils: large but infrequent earthquakes. Becoming quake resilient is a small price to pay for living in such a great part of the world, and it is achievable at modest cost.

    A personal solution to a global problem

    Half of the world’s population lives near active faults, but most of us are unaware of this. You can learn if you are at risk and protect your home, land, and family.

    Temblor enables everyone in the continental United States, and many parts of the world, to learn their seismic, landslide, tsunami, and flood hazard. We help you determine the best way to reduce the risk to your home with proactive solutions.

    Earthquake maps, soil liquefaction, landslide zones, cost of earthquake damage

    In our iPhone and Android and web app, Temblor estimates the likelihood of seismic shaking and home damage. We show how the damage and its costs can be decreased by buying or renting a seismically safe home or retrofitting an older home.

    Please share Temblor with your friends and family to help them, and everyone, live well in earthquake country.

    Temblor is free and ad-free, and is a 2017 recipient of a highly competitive Small Business Innovation Research (‘SBIR’) grant from the U.S. National Science Foundation.

    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

     
  • richardmitnick 4:23 pm on November 30, 2017 Permalink | Reply
    Tags: , Early elasto-gravitational earthquake signals are finally reported - Science article in list of references, , , , P waves, S waves, , Superconductive gravimeter, temblor   

    From temblor- “Earthquake Early Warning: Gravity changes beat seismic signals” 

    1

    temblor

    November 30, 2017
    Jean Paul Ampuero, Caltech Seismological Laboratory; Université Côte d’Azur, IRD, Géoazur

    1
    The devastating 2011 Tohoku earthquake and ensuing tsunami caused billions of dollars of damage and the deaths of thousands. A new study, using data from this quake, suggests that small gravity changes are the earliest earthquake early warning signals. Photo from: SFDEM

    This story starts a few years ago, when astrophysicists in search for gravitational waves from the distant universe crossed paths with seismologists starving for new clues about how earthquakes work beneath our feet. Someone’s noise soon became someone else’s signal, indeed a very unique signal: the earliest harbinger of earthquake shaking that nature and physics have to offer.

    Earthquakes move mass around, in enormous quantities. This is obvious to anyone who has been mesmerized by the view of fault offsets of several meters left at the Earth’s surface after a large earthquake. But mass is also redistributed temporarily by seismic waves, even before the earthquake is over. For example, P waves compress and dilate the rock they travel through, perturbing the rock’s density momentarily. These static and dynamic mass perturbations are natural sources of gravity changes … and gravity changes travel remotely at the speed of light!

    Earthquake early warning (EEW), which aims at alerting people and automated systems seconds before strong shaking arrives, is one of the important contributions of modern seismology to society. But current EEW systems have a fundamental limitation: the natural information carrier they rely on, P waves, travels only about twice as fast as the natural damage carrier they try to anticipate, S waves. Just like lightning warns us of impending thunder, speed-of-light gravity changes are, in principle, the ultimately-fast earthquake information carrier.

    Our team, a mix of physicists and seismologists in the US and Europe, used pen-and-paper and supercomputers to make a first theoretical estimation of how large these early gravity signals could be (Harms et al, 2015). The results looked “promising”: observing the phenomenon with current instrumentation promised to be a nice challenge. Our best bet was then to look for recordings of the huge 2011 Tohoku, Japan earthquake by a superconductive gravimeter installed in a quiet underground site, 500 km away from the epicenter, and by nearby broadband seismic stations. A blind statistical analysis of the data (of the type our gravitational-wave astrophysics colleagues are used to) revealed evidence of a signal preceding the P waves (Montagner et al, 2016). But it was not the smoking gun one would have hoped for. Moreover, my Caltech colleague Prof. Tom Heaton pointed out (Heaton, 2017) that our theory did not account for a potentially important feedback of gravity changes on elastic deformation, which I describe below.

    The smoking gun and a more complete theory of early elasto-gravitational earthquake signals are finally reported in our paper published this week in Science Magazine (Vallée et al, 2017). We found that broadband seismometers in China located between 1,000 and 2,000 km away from the epicenter recorded, consistently and with high signal-to-noise ratio, an emergent signal that preceded the arrival of P waves from the Tohoku earthquake by more than one minute. These signals are well predicted by the results of a new simulation method we developed to account for the following physical process. The gravity perturbations induced directly by earthquakes (those studied by Harms et al, 2015) also act as distributed forces that deform the crust and produce ground acceleration. Gravimeters and seismometers are inertial sensors coupled to the ground, they actually record the difference between gravitational acceleration and ground acceleration. Sometimes these two accelerations are of comparable amplitude and tend to cancel each other, thus it is important to include both in simulations.

    2
    This figure, modified from IPGP, 2017, shows the signal picked up by a seismometer in the time preceding and following the 2011 M=9.1 Tohoku earthquake. What is important to see in this figure is that there is a 45-60 second window from when the prompt signal drops below normal background rates, until a P wave can be felt. This represents the potential earthquake early warning time. (Figure from Vallée et al., 2017)

    How can we use these results to improve current EEW systems? Elasto-gravitational signals carry information about earthquake size but are weak and do not have a sharp onset. We had to use very distant seismic stations and wait more than one minute after the Tohoku mega-earthquake started to see its elasto-gravitational signals on conventional seismometers. This seems too long a wait for an EEW system, but it is enough to significantly accelerate current tsunami warning systems. Indeed our simulations show that the Chinese stations could distinguish earthquakes in Japan with Mw<8.5 from much larger ones within a few minutes (Vallée et al, 2017). This capability may be improved in the near future by exploiting modern array techniques to mitigate microseism noise. Who would have thought that a broadband seismic network in the Brazilian Amazon could someday help warn the megacity of Lima, Peru of an impending tsunami?

    To develop the full potential of elasto-gravity signals for EEW (and, more fundamentally, for earthquake source studies) we need to develop new, more sensitive instruments. We can leverage on technological advances in gravity gradiometry for low-frequency gravitational wave (GW) detection. The GW detections that led to the recent Nobel Prize were achieved at frequencies of about 100 Hz and required huge facilities, but the GW astronomy community is also interested in observing GW signals in the 0.1-1 Hz band with much lighter and smaller (meter scale) instrumentation. The sensor requirements for EEW are much less stringent than those for GW detection, and should be achieved much sooner.

    My personal affair with this new field of gravitational seismology started with a scholar chat at the Caltech Seismolab with Jan Harms, who was then a LIGO postdoc, and continued soon after with my old-time friends from IPG Paris. It has been wonderful to experience first-hand that EEW research is not only about operational and engineering aspects, but also about fundamental physics problems. I also find it exciting that the ongoing revolution of gravitational wave astronomy will not only open new windows into the distant Universe but also into our own vulnerable Earth.

    References

    J. Harms, J. P. Ampuero, M. Barsuglia, E. Chassande-Mottin, J.-P. Montagner, S. N. Somala and B. F. Whiting (2015), Transient gravity perturbations induced by earthquake rupture, Geophys. J. Int., 201 (3), 1416-1425, doi: 10.1093/gji/ggv090

    T. H. Heaton (2017), Correspondence: Response of a gravimeter to an instantaneous step in gravity, Nature Comm., 8 (1), 966, doi: 10.1038/s41467-017-01348-z

    J.-P. Montagner, K. Juhel, M. Barsuglia, J. P. Ampuero, E. Chassande-Mottin, J. Harms, B. Whiting, P. Bernard, E. Clévédé, P. Lognonné (2016), Prompt gravity signal induced by the 2011 Tohoku-oki earthquake, Nat. Comm., 7, 13349, doi: 10.1038/ncomms13349

    M. Vallée, J. P. Ampuero, K. Juhel, P. Bernard, J.-P. Montagner, M. Barsuglia (December 1st 2017), Observations and modeling of the elastogravity signals preceding direct seismic waves, Science, doi: 10.1126/science.aao0746

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    You can help many citizen scientists in detecting earthquakes and getting the data to emergency services people in affected area.
    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).

    BOINCLarge

    BOINC WallPaper

    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

    Earthquake country is beautiful and enticing

    Almost everything we love about areas like the San Francisco bay area, the California Southland, Salt Lake City against the Wasatch range, Seattle on Puget Sound, and Portland, is brought to us by the faults. The faults have sculpted the ridges and valleys, and down-dropped the bays, and lifted the mountains which draw us to these western U.S. cities. So, we enjoy the fruits of the faults every day. That means we must learn to live with their occasional spoils: large but infrequent earthquakes. Becoming quake resilient is a small price to pay for living in such a great part of the world, and it is achievable at modest cost.

    A personal solution to a global problem

    Half of the world’s population lives near active faults, but most of us are unaware of this. You can learn if you are at risk and protect your home, land, and family.

    Temblor enables everyone in the continental United States, and many parts of the world, to learn their seismic, landslide, tsunami, and flood hazard. We help you determine the best way to reduce the risk to your home with proactive solutions.

    Earthquake maps, soil liquefaction, landslide zones, cost of earthquake damage

    In our iPhone and Android and web app, Temblor estimates the likelihood of seismic shaking and home damage. We show how the damage and its costs can be decreased by buying or renting a seismically safe home or retrofitting an older home.

    Please share Temblor with your friends and family to help them, and everyone, live well in earthquake country.

    Temblor is free and ad-free, and is a 2017 recipient of a highly competitive Small Business Innovation Research (‘SBIR’) grant from the U.S. National Science Foundation.

    ShakeAlert: Earthquake Early Warning

    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 by 2018.

    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, depending on the distance to the epicenter of the earthquake. For very large events like those expected on the San Andreas fault zone or the Cascadia subduction zone the warning time could be much longer because the affected area is much larger. ShakeAlert can give enough time to slow and stop 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 by 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” test 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. This “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

     
  • richardmitnick 11:38 pm on November 12, 2017 Permalink | Reply
    Tags: , , , , , , temblor   

    From temblor: “Damaging Magnitude 7.3 earthquake along the Iran-Iraq border was preceded by Magnitude 4.3 foreshock” 

    1

    temblor

    November 12, 2017
    Ross S. Stein, Ph.D., Temblor

    A powerful, shallow earthquake struck along the Iraq-Iran border today. Damage is currently largely unknown, but is likely heavy because of the poor capacity of rural housing in this region to resist seismic shaking. This was tragically demonstrated when the 2003 M=6.3 Bam, Iran, earthquake took 26,000 lives due to the almost complete collapse of ancient adobe dwellings. Also, a M=5.3 aftershock hit 10 minutes after the mainshock, which is large enough to bring down a building damaged by the first event.

    The quake struck in a region of very low background seismicity

    Although both Iraq and Iran are seismically active, and even though the quake lies only 100 km (60 mi) from the compressional boundary between the Arabian and Eurasian plates, there were no M≥4.5 quakes within about 60 km (35 mi) of today’s epicenter during the past 20 years.

    1
    The completeness magnitude for this region is likely about M=4.5 since 1997, and so we use those to assess the background, or preceding seismicity, and find it to be very sparse.

    M=4.3 foreshock an hour before the mainshock

    Nevertheless, unless the EMSC catalog suffers from timing errors, there was a M=4.3 ‘foreshock’ one hour before the mainshock, located about 60 km (35 mi) to the southwest of the future mainshock. Given how low the background rate is, this occurrence might indicate that the gently-dipping thrust fault on which the mainshock struck was undergoing precursory creep. The occurrence of foreshocks is rare, and as indicators of future mainshocks or even creep, unreliable.

    2
    The foreshock struck rather far from the mainshock, but could indicate deep precursory creep.

    Is this a very rare event?

    According to the ISC-GEM seismic catalog, the closest large events since 1900 were a pair of M=6.7 and M=6.8 events in 1957-1958, some 200 km (120 mi) to the southeast of today’s mainshock.

    Broadly, the Arabia tectonic plate is being shoved against Eurasia plate along the Bitlis Suture and Zagros fold belt at a speed of 26 mm/yr (1 in/yr). This is the same slip rate as the San Andreas Fault. But because the almost no M≥5.8 quakes struck in this region for the past 40 years, and the because local strain rate is not adequately measured by GPS, the Global Earthquake Activity Rate (GEAR) model shown in Temblor expects only a M=5.5-5.8 in a typical lifetime in this area. But the political and military conflicts in the region have prevented adequate GPS monitoring.

    3
    Today’s earthquake sequence struck along two borders: political and tectonic.

    So, either this event is indeed quite rare, or the absence of GPS data has created artificial quake ‘hole’ in the GEAR model.

    References: USGS ANSS catalog, ESMC catalog, ISC-GEM catalog
    Sorry, no links.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    You can help many citizen scientists in detecting earthquakes and getting the data to emergency services people in affected area.
    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).

    BOINCLarge

    BOINC WallPaper

    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

    Earthquake country is beautiful and enticing

    Almost everything we love about areas like the San Francisco bay area, the California Southland, Salt Lake City against the Wasatch range, Seattle on Puget Sound, and Portland, is brought to us by the faults. The faults have sculpted the ridges and valleys, and down-dropped the bays, and lifted the mountains which draw us to these western U.S. cities. So, we enjoy the fruits of the faults every day. That means we must learn to live with their occasional spoils: large but infrequent earthquakes. Becoming quake resilient is a small price to pay for living in such a great part of the world, and it is achievable at modest cost.

    A personal solution to a global problem

    Half of the world’s population lives near active faults, but most of us are unaware of this. You can learn if you are at risk and protect your home, land, and family.

    Temblor enables everyone in the continental United States, and many parts of the world, to learn their seismic, landslide, tsunami, and flood hazard. We help you determine the best way to reduce the risk to your home with proactive solutions.

    Earthquake maps, soil liquefaction, landslide zones, cost of earthquake damage

    In our iPhone and Android and web app, Temblor estimates the likelihood of seismic shaking and home damage. We show how the damage and its costs can be decreased by buying or renting a seismically safe home or retrofitting an older home.

    Please share Temblor with your friends and family to help them, and everyone, live well in earthquake country.

    Temblor is free and ad-free, and is a 2017 recipient of a highly competitive Small Business Innovation Research (‘SBIR’) grant from the U.S. National Science Foundation.

    ShakeAlert: Earthquake Early Warning

    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 by 2018.

    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, depending on the distance to the epicenter of the earthquake. For very large events like those expected on the San Andreas fault zone or the Cascadia subduction zone the warning time could be much longer because the affected area is much larger. ShakeAlert can give enough time to slow and stop 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 by 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” test 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. This “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

     
  • richardmitnick 9:14 am on September 20, 2017 Permalink | Reply
    Tags: , M=7.1 earthquake collapses buildings in Mexico City on the 32nd anniversary of a deadly M=8.0 quake, , , temblor   

    From temblor: “M=7.1 earthquake collapses buildings in Mexico City on the 32nd anniversary of a deadly M=8.0 quake” 

    1

    temblor

    September 19, 2017
    David Jacobson, Temblor
    Professor Shinji Toda,
    IRIDeS, Tohoku University, Japan

    1
    This Temblor map shows the location of today’s M=7.1 earthquake just south of the country’s capital, Mexico City.

    At 1:14 p.m. local time, a M=7.1 earthquake struck just south of Puebla, Mexico, and 120 km from Mexico City, where almost 9 million people reside. From the initial USGS ShakeMap, severe shaking was felt close to the epicenter, while in Mexico City, they would have experienced moderate to strong shaking, enough to cause significant damage. Ironically, this earthquake comes on the 32nd anniversary of a deadly M=8.0 earthquake in Mexico City which killed over 5,000 people and caused billions in damage. Furthermore, as an observance to the anniversary, several buildings held earthquake drills earlier in the day. Unlike today’s quake, which struck southeast of the city, that earthquake was centered over 350 km to the southwest of the capital.

    Based on reports and photos, we know that at least 42 people are confirmed to have died, and buildings have collapsed in Mexico City. The USGS PAGER system estimates that economic losses could reach $1 billion, with up to 1,000 fatalities. This deadly quake comes less than 2 weeks after a M=8.1 earthquake shook the Chiapas region to the southeast. While the magnitude of that quake was significantly larger than today’s, shaking in Mexico City was greater today, given the proximity of the epicenter to the city.

    2
    Today’s M=7.1 earthquake south of Mexico City resulted in significant damage throughout the city. (Photo from: Ronaldo Schemidt/Agence France-Presse — Getty Images)

    Despite the fact that just offshore of Mexico is the Middle America Trench, where the Cocos plate subducts beneath the North American plate at a rate of approximately 76 mm/yr, today’s event, like the earthquake on Sept 7, was extensional in nature. Depending on the subduction model used, today’s earthquake could have either been within the subducting Cocos plate (Franco et al., 2005), or the overriding North American plate (Hayes et al., 2012). This difference is a matter of how much the dip of the subducting slab shallows. Professor Shinji Toda at IRIDeS, Tohoku University, Japan, says that while intraslab earthquakes are typically not as destructive as subduction zone events, their sources are totally invisible and are thus extremely unpredictable. Additionally, he suggests that while inland Mexico is dominated by subduction megathrust events and onshore active faults, a flattened slab layer could be a third source of large earthquakes.

    3
    This figure, which has been modified from Franco et al., 2005 shows the location of the two large recent earthquake in Mexico. Additionally, it shows the rupture areas of other large historic earthquakes in the country. Lastly, this figure highlights how both of the large earthquakes in the last two weeks were likely intraplate events within the subducting Cocos Plate.

    From the focal mechanism and location of today’s event, it may have struck within the Trans-Mexican Volcanic Belt. While this chain of active volcanoes is the product of subduction at the Middle America Trench, there is regional extension. Throughout this volcanic belt, which runs across central Mexico, there are pronounced east-west-oriented extensional faults. Based on historical earthquakes, there is no known subduction zone seismicity below the Trans-Mexican Volcanic Belt (Suter et al., 2001). This means that any earthquake within this zone is likely to be extensional.

    From the Global Earthquake Activity Rate (GEAR) model, which is available in Temblor, today’s M=7.1 earthquake just south of Mexico City can be considered surprising. This model uses global strain rates and the last 40 years of seismicity to forecast the likely earthquake magnitude in your lifetime anywhere on earth. From this model, which is shown below, one can see that in the location of today’s event, the likely magnitude is M=6.5-6.75. Having said that, in 1999, a M=7.0 earthquake struck just roughly 100 km to the east. That too was an extensional earthquake likely associated with the Trans-Mexican Volcanic Belt. As more information comes in on this earthquake, we will either update this blog, or post an entirely new one.

    4
    This Temblor map shows the Global Earthquake Activity Rate (GEAR) model for much of Mexico as well as the locations of today’s M=7.1 earthquake, and the M=8.1 quake less than two weeks ago. What this map shows is that based on their magnitudes, both of these quakes should be considered relatively surprising.

    References [No links]
    USGS
    European-Mediterranean Seismological Centre
    Max Suter, Margarita Lopez Martınez, Odranoel Quintero Legorreta, and Miguel Carrillo Martınez, Quaternary intra-arc extension in the central Trans-Mexican volcanic belt, GSA Bulletin; June 2001; v. 113; no. 6; p. 693–703
    Franco et al., Propagation of the 2001-2002 silent earthquake and interplate coupling in the Oaxaca subduction zone, Mexico, Earth Planets and Space · October 2005

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    You can help many citizen scientists in detecting earthquakes and getting the data to emergency services people in affected area.
    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).

    BOINCLarge

    BOINC WallPaper

    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

    Earthquake country is beautiful and enticing

    Almost everything we love about areas like the San Francisco bay area, the California Southland, Salt Lake City against the Wasatch range, Seattle on Puget Sound, and Portland, is brought to us by the faults. The faults have sculpted the ridges and valleys, and down-dropped the bays, and lifted the mountains which draw us to these western U.S. cities. So, we enjoy the fruits of the faults every day. That means we must learn to live with their occasional spoils: large but infrequent earthquakes. Becoming quake resilient is a small price to pay for living in such a great part of the world, and it is achievable at modest cost.

    A personal solution to a global problem

    Half of the world’s population lives near active faults, but most of us are unaware of this. You can learn if you are at risk and protect your home, land, and family.

    Temblor enables everyone in the continental United States, and many parts of the world, to learn their seismic, landslide, tsunami, and flood hazard. We help you determine the best way to reduce the risk to your home with proactive solutions.

    Earthquake maps, soil liquefaction, landslide zones, cost of earthquake damage

    In our iPhone and Android and web app, Temblor estimates the likelihood of seismic shaking and home damage. We show how the damage and its costs can be decreased by buying or renting a seismically safe home or retrofitting an older home.

    Please share Temblor with your friends and family to help them, and everyone, live well in earthquake country.

    Temblor is free and ad-free, and is a 2017 recipient of a highly competitive Small Business Innovation Research (‘SBIR’) grant from the U.S. National Science Foundation.

    ShakeAlert: Earthquake Early Warning

    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 by 2018.

    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, depending on the distance to the epicenter of the earthquake. For very large events like those expected on the San Andreas fault zone or the Cascadia subduction zone the warning time could be much longer because the affected area is much larger. ShakeAlert can give enough time to slow and stop 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 by 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” test 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. This “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

     
  • richardmitnick 4:21 pm on September 8, 2017 Permalink | Reply
    Tags: , M=8 earthquake strikes offshore Mexico, temblor   

    From temblor: “M=8 earthquake strikes offshore Mexico” 

    1

    temblor

    September 7, 2017
    David Jacobson

    At 11:49 p.m. local time, a M=8.0 earthquake struck offshore Mexico at a depth of 69 km according to the USGS (The European-Mediterranean Seismological Centre assigned it a depth of 61 km). In the six hours following the mainshock, there have been 28 M=4.3+ aftershocks, which have caused further panic in Mexico. This quake occurred approximately 80 km offshore, and triggered a tsunami warning for Mexico, Guatemala, Panama, El Salvador, Costa Rica, Nicaragua, Honduras and Ecuador. As of 6 a.m. Pacific time, the largest waves recorded were 2.3 feet.

    1
    This Temblor map shows the location of tonight’s M=8.0 earthquake off the coast of Mexico. According to the USGS, the quake struck at a depth of 69 km, and registered violent shaking near the epicenter.

    This massive earthquake took place on the Middle America Trench, where the Cocos Plate subducts beneath the North American Plate at a rate of roughly 80 mm/yr. Because of the magnitude of this quake, it was felt as far away as Mexico City and Guatemala City, which combined, are home to over 10 million people. Based on the USGS ShakeMap, and regional populations, over 40 million people would have felt this earthquake at varying degrees of severity. According to the New York Times, panicked residents in Mexico City rushed into the streets as their buildings swayed. Even though USGS PAGER system forecasts that fatalities will be between 1,000 and 10,000, so far, there are only 15 confirmed. However, because this earthquake happened at night, this number is sure to rise. The USGS PAGER system also predicts that economic losses will likely total more than $1 billion. Initial reports suggest that there are several collapsed buildings close to the epicenter.

    Despite the fact that this earthquake occurred near the Middle America Trench, a compressional environment, the initial (as of 11 p.m. Pacific Time) USGS focal mechanism suggests that this quake was due to extensional motion. Based on the depth of the quake (69 km) it struck below the subduction zone, meaning the extensional nature could be due to a changing dip angle in the subducting slab. However, it is also possible that in the coming hours, new data will arrive, and if it does, we will be sure to update this post.

    Based on the Global Earthquake Activity Rate (GEAR) model, which is available in Temblor, this M=8.0 earthquake can be considered relatively surprising. This model uses global strain rates and the last 40 years of seismicity to forecast the likely earthquake magnitude in your lifetime anywhere on earth. From the figure below, one can see that in this area off the coast of Mexico, the likely magnitude in your lifetime is 7.25. This highlights the unpredictability of earthquakes, and that in areas susceptible to large quakes, people need to be aware of the risks and protect themselves in any ways possible.

    2
    his Temblor map shows the Global Earthquake Activity Rate (GEAR) model for the area around tonight’s M=8.0 earthquake. This model uses global strain rates and the last 40 years of seismicity to forecast the likely earthquake magnitude in your lifetime anywhere on earth. Based on this model, tonight’s M=8.0 earthquake can be considered surprising as the expected magnitude to occur in your lifetime in this area is M=7.25.

    References [no links]
    USGS
    EMSC
    New York Times
    CNN

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    You can help many citizen scientists in detecting earthquakes and getting the data to emergency services people in affected area.
    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).

    BOINCLarge

    BOINC WallPaper

    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

    Earthquake country is beautiful and enticing

    Almost everything we love about areas like the San Francisco bay area, the California Southland, Salt Lake City against the Wasatch range, Seattle on Puget Sound, and Portland, is brought to us by the faults. The faults have sculpted the ridges and valleys, and down-dropped the bays, and lifted the mountains which draw us to these western U.S. cities. So, we enjoy the fruits of the faults every day. That means we must learn to live with their occasional spoils: large but infrequent earthquakes. Becoming quake resilient is a small price to pay for living in such a great part of the world, and it is achievable at modest cost.

    A personal solution to a global problem

    Half of the world’s population lives near active faults, but most of us are unaware of this. You can learn if you are at risk and protect your home, land, and family.

    Temblor enables everyone in the continental United States, and many parts of the world, to learn their seismic, landslide, tsunami, and flood hazard. We help you determine the best way to reduce the risk to your home with proactive solutions.

    Earthquake maps, soil liquefaction, landslide zones, cost of earthquake damage

    In our iPhone and Android and web app, Temblor estimates the likelihood of seismic shaking and home damage. We show how the damage and its costs can be decreased by buying or renting a seismically safe home or retrofitting an older home.

    Please share Temblor with your friends and family to help them, and everyone, live well in earthquake country.

    Temblor is free and ad-free, and is a 2017 recipient of a highly competitive Small Business Innovation Research (‘SBIR’) grant from the U.S. National Science Foundation.

    ShakeAlert: Earthquake Early Warning

    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 by 2018.

    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, depending on the distance to the epicenter of the earthquake. For very large events like those expected on the San Andreas fault zone or the Cascadia subduction zone the warning time could be much longer because the affected area is much larger. ShakeAlert can give enough time to slow and stop 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 by 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” test 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. This “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

     
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