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  • richardmitnick 1:14 pm on April 22, 2019 Permalink | Reply
    Tags: "More Than a Million New Earthquakes Spotted in Archival Data", AGU, , Earthquakes in California,   

    From Eos: “More Than a Million New Earthquakes Spotted in Archival Data” 

    From AGU
    Eos news bloc

    From Eos

    19 April 2019
    Katherine Kornei
    hobbies4kk@gmail.com

    By reanalyzing seismic records, researchers found a plethora of tiny earthquakes in Southern California that trace new fault structures and reveal how earthquakes are triggered.

    1
    Little temblors like those detected in the new data are much more numerous than the building-toppling quakes like the one that ripped through San Francisco in 1906. Credit: The U.S. National Archives

    Every 3 minutes. That’s how often an earthquake struck Southern California from 2008 to 2017, new research published in Science shows.

    3
    National Geographic

    Scientists have discovered over 1.6 million previously unknown earthquakes, most of them tiny, by mining seismic records. These results, which constitute the most comprehensive earthquake catalog produced to date, reveal in detail how faults crisscross the Golden State and shed light on how one earthquake triggers others.

    “Having a better earthquake catalog is just like having a better microscope,” said Robert Skoumal, a geophysicist at the U.S. Geological Survey in Menlo Park, Calif., not involved in this study. “We are able to take a closer look at the location of faults, how those faults rupture, and how they interact with each other.”

    Small and Numerous

    A tenet of earthquake science motivated Zachary Ross, a seismologist at the California Institute of Technology in Pasadena, and his collaborators: Earthquake catalogs are always incomplete. That’s because small earthquakes, many of which are too tiny to feel, are always lurking below the limit of detectability. And these little temblors are much more numerous than the building-toppling, highway-churning beasts that make headlines.

    “For every magnitude unit you go down in size, you get about 10 times as many,” said Ross.

    Ross and his colleagues used data from over 500 seismometers in the Southern California Seismic Network to tease out small, previously unrecorded earthquakes.

    They used a technique called template matching, which involves using the seismic waveforms of known earthquakes as templates and then looking for matches in seismic data collected nearby.

    “The shaking that’s recorded…will look almost the same,” said Ross. “They’re seeing all the same rocks as they’re traveling along.”

    Down to the Noise

    “We’re basically at the noise level of the instrumentation.”
    Ross and his team combed through a decade of seismic records using over 280,000 earthquakes as template events. They found over 1.6 million new earthquakes as small as magnitude 0.3. Such low levels of ground shaking can also be caused by construction-related vibrations, ocean waves, and nearby aircraft, said Ross.

    “We’re basically at the noise level of the instrumentation.”

    Using small differences in the arrival times of seismic waves from an earthquake, the scientists calculated the hypocenter of each new event. This information, along with an earthquake’s timing and magnitude, allowed Ross and his colleagues to assemble detailed maps of Southern California’s earthquakes.


    Video by Caltech

    The new earthquake catalog does a far better job of tracing fault lines and revealing how earthquakes trigger others compared with older records, said Ross.

    See the full article here .

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  • richardmitnick 3:50 pm on March 25, 2019 Permalink | Reply
    Tags: AGU, , , , , WOVO-World Organization of Volcano Observatories   

    From Eos: “Data from Past Eruptions Could Reduce Future Volcano Hazards” 

    From AGU
    Eos news bloc

    From Eos

    3.25.19
    Fidel Costa
    Christina Widiwijayanti
    Hanik Humaida

    Optimizing the Use of Volcano Monitoring Database to Anticipate Unrest; Yogyakarta, Indonesia, 26–29 November 2018.

    1
    Java’s Mount Merapi volcano (right), overlooking the city of Yogyakarta, is currently slowly extruding a dome. Mount Merbabu volcano (left) has not erupted for several centuries. Participants at a workshop last November discussed the development and use of a volcano monitoring database to assist in mitigating volcano hazards. Credit: Fidel Costa

    In 2010, Mount Merapi volcano on the Indonesian island of Java erupted explosively—the largest such eruption in 100 years.

    1
    Mount Merapi, viewed from Umbulharjo
    16 April 2014
    Crisco 1492

    Merapi sits only about 30 kilometers from the city of Yogyakarta, home to more than 1 million people. The 2010 eruption forced more than 390,000 people to evacuate the area, and it caused 386 fatalities. In the past few months, the volcano has started rumbling again, and it is currently extruding a dome that is slowly growing.

    Will Merapi’s rumblings continue like this, or will they turn into another large, explosive eruption? Answering this question largely depends on having real-time monitoring data covering multiple parameters, including seismicity, deformation, and gas emissions. But volcanoes can show a wide range of behaviors. A volcanologist’s diagnosis of what the volcano is going to do next relies largely on comparisons to previous cases and thus on the existence of an organized and searchable database of volcanic unrest.

    For over a decade, the World Organization of Volcano Observatories (WOVO) has contributed to the WOVOdat project, which has collected monitoring data from volcanoes worldwide. WOVOdat has grown into an open-source database that should prove very valuable during a volcanic crisis. However, there are many challenges ahead to reaching this goal:

    How do we standardize and capture spatiotemporal data produced in a large variety of formats and instruments?
    How do we go from multivariate (geochemical, geophysical, and geodetic) signals to statistically meaningful indicators for eruption forecasts?
    How do we properly compare periods of unrest between volcanic eruptions?

    Participants at an international workshop last November discussed these and other questions. The workshop was organized by the Earth Observatory of Singapore and the Center for Volcanology and Geological Hazard Mitigation in Yogyakarta. An interdisciplinary group of over 40 participants, including students and experts from more than 10 volcano observatories in Indonesia, the Philippines, Papua New Guinea, Japan, France, Italy, the Caribbean, the United States, Chile, and Singapore, gathered to share their expertise on handling volcano monitoring data, strategize on how to improve on monitoring data management, and analyze past unrest data to better anticipate future unrest and eruptions.

    Participants agreed on the need for a centralized database that hosts multiparameter monitoring data sets and that allows efficient data analysis and comparison between a wide range of volcanoes and eruption styles. They proposed the following actions to optimize the development and use of a monitoring database:

    develop automatic procedures for data processing, standardization, and rapid integration into a centralized database platform
    develop tools for diagnosis of unrest patterns using statistical analytics and current advancement of machine learning techniques
    explore different variables, including eruption styles, morphological features, eruption chronology, and unrest indicators, to define “analogue volcanoes” (classes of volcanoes that behave similarly) and “analogue unrest” for comparative studies
    develop protocols to construct a short-term Bayesian event tree analysis based on real-time data and historical unrest

    Volcano databases such as WOVOdat aim to be a reference for volcanic crisis and hazard mitigation and to serve the community in much the same way that an epidemiological database serves for medicine. But the success of such endeavors requires the willingness of observatories, governments, and researchers to agree on data standardization; efficient data reduction algorithms; and, most important, data sharing to enable findable, accessible, interoperable, and reusable (FAIR) data across the volcano community.

    —Fidel Costa (fcosta@ntu.edu.sg), Earth Observatory of Singapore and Asian School of the Environment, Nanyang Technological University, Singapore; Christina Widiwijayanti, Earth Observatory of Singapore, Nanyang Technological University, Singapore; and Hanik Humaida, Center for Volcanology and Geological Hazard Mitigation, Geological Agency of Indonesia, Bandung

    See the full article here .

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    Please help promote STEM in your local schools.

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

     
  • richardmitnick 1:23 pm on March 22, 2019 Permalink | Reply
    Tags: "New Antenna Design Could Improve Satellite Communications", AGU, Circular polarization of the signal allows for disturbances in the atmosphere that cause the electromagnetic signal to rotate as it travels to and from the ground, Circular polarization of the signal allows the satellite and the ground station to maintain communication even if the satellite rotates relative to the receiver, , The data collected by a satellite are only as good as the signal it sends back to Earth and the signal it sends back is only as good as the antenna that sends it, Turkmen and Secmen design model and fabricate a new type of omnidirectional and circularly polarized slotted antenna that improves on existing designs in a number of ways.   

    From Eos: “New Antenna Design Could Improve Satellite Communications” 

    From AGU
    Eos news bloc

    From Eos

    14 March 2019
    David Shultz

    1
    The new omnidirectional circularly polarized slotted antenna. Credit: Turkmen and Secmen [2018]

    A novel antenna design promises to improve bandwidth and allow for better communication between Earth stations and satellites.

    The data collected by a satellite are only as good as the signal it sends back to Earth, and the signal it sends back is only as good as the antenna that sends it. Modern satellites come equipped with various sorts of antennas, all of which are designed to send and receive data by transmitting and interpreting pulses of electromagnetic radiation. Most satellites operate in a portion of the microwave spectrum known as the Kᵤ band, which spans wavelengths ranging from 1.67 to 2.5 centimeters and frequencies between 12 and 18 gigahertz.

    In a new study, Turkmen and Secmen [Radio Science] design, model, and fabricate a new type of omnidirectional and circularly polarized slotted antenna that improves on existing designs in a number of ways. The word “omnidirectional” is used to describe antennas that transmit their signal isotropically, meaning the pattern of radiation is the same no matter where the receiver is placed relative to the transmitter. Although perfectly isotropic transmission remains impossible, researchers can manipulate the signal in several ways to reduce its directionality. Omnidirectional antennas have several advantages, most notably in their ability to transmit around landforms such as mountains or, in the case of satellites, around the curvature of Earth, allowing researchers to maintain constant contact with the orbiter and detect any faults.

    Similarly, circular polarization of the signal allows the satellite and the ground station to maintain communication even if the satellite rotates relative to the receiver or if disturbances in the atmosphere cause the electromagnetic signal to rotate as it travels to and from the ground.

    Here the authors propose a new antenna designed to create the truest omnidirectional radiation pattern yet. It uses a special waveguide (a hollow structure that controls and aims the electromagnetic radiation) that transitions from a rectangular shape to a cylindrical one (see the image above). Like a sound wave traveling through an organ pipe, the satellite signal propagates through the wave guide, and the unique shape coaxes the signal into a pattern known as the TM01 mode, which also improves the omnidirectionality of the signal.

    To improve the signal’s quality even further, the researchers placed nonidentical antennae array slots in a geometrically symmetric pattern along the waveguide (see the image above). This modification was done to decrease the gain variation in the signal in the azimuthal plane in a wider frequency bandwidth. Gain describes how much a signal is amplified, and low variations in gain are crucial for achieving an omnidirectional radiation pattern. The end result, the researchers say, doubles the bandwidth of the satellite at the 12-gigahertz frequency.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

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

     
  • richardmitnick 2:24 pm on February 18, 2019 Permalink | Reply
    Tags: AGU, , , , Rising Temperatures Reduce Colorado River Flow   

    From Eos: “Rising Temperatures Reduce Colorado River Flow” 

    From AGU
    Eos news bloc

    From Eos

    2.18.19
    Sarah Stanley

    1
    New research teases out the relative roles of hotter temperatures and declining precipitation in reducing the flow volume of the Colorado River, which feeds Lake Mead, pictured here [and much more]. Credit: John Fleck

    The Colorado River flows through seven U.S. states and northern Mexico, before discharging into the Gulf of California. Along the way, it provides drinking water to millions of people and irrigates thousands of square kilometers of cropland. However, although annual precipitation in the region increased by about 1% in the past century, the volume of water flowing down the river has dropped by over 15%.

    New research by Xiao et al. [Water Resources Research]. examines the causes behind this 100-year decline in natural flow, teasing out the relative contributions of rising temperatures and changes in precipitation. This work builds on a 2017 paper [Water Resources Research] showing that rising temperatures played a significant role in reduced flows during the Millennium Drought between 2000 and 2014.

    Rising temperatures can lower flow by increasing the amount of water lost to evaporation from soil and surface water, boosting the amount of water used by plants, lengthening the growing season, and shrinking snowpacks that contribute to flow via meltwater.

    To investigate the impact of rising temperatures on Colorado River flow over the past century, the authors of the new paper employed the Variable Infiltration Capacity (VIC) hydrologic model. The VIC model enabled them to simulate 100 years of flow at different locations throughout the vast network of tributaries and subbasins that make up the Colorado River system and to tease out the effects of long-term changes in precipitation and temperature throughout the entire Colorado River.

    The researchers found that rising temperatures are responsible for 53% of the long-term decline in the river’s flow, with changing precipitation patterns and other factors accounting for the rest. The sizable effects of rising temperatures are largely due to increased evaporation and water uptake by plants, as well as by sublimation of snowpacks.

    Additional simulations with the VIC model showed that warming drove 54% of the decline in flow seen during the Millennium Drought, which began in 2000 (and is ongoing). Flows also declined because precipitation fell on less productive (i.e., more arid) subbasins rather than on highly productive subbasins near the Continental Divide. This contrasts strongly with an earlier (1950s–1960s) drought of similar severity, which was caused almost entirely by below-normal precipitation over most of the basin.

    The authors note that the situation is complex, given different long-term trends and drought response across the basin, as well as seasonal differences in temperature and precipitation. Still, the new findings support an argument from the 2017 research that as global warming progresses, the relative contribution of rising temperatures to decreased Colorado River flow will increase.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

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

     
  • richardmitnick 3:49 pm on January 28, 2019 Permalink | Reply
    Tags: AGU, , NASA Magnetospheric Multiscale Mission,   

    From Eos: “New Plasma Wave Observations from Earth’s Magnetosphere” 

    From AGU
    Eos news bloc

    From Eos

    1.28.19
    Terri Cook

    NASA Magnetospheric Multiscale Mission

    Plasmas are swirling mixtures of gas so hot that many of the constituent atoms have been stripped of their electrons, creating a dynamic field of both negatively and positively charged particles that are strongly influenced by magnetic and electrical fields. Plasmas account for more than 99% of matter in the universe and can disrupt satellite navigation systems and other technologies, but scientists are still working to understand the fundamental processes occurring within them.

    Usanova et al. report new observations of plasma waves in the magnetosphere, the region surrounding our planet where Earth’s magnetic field controls the charged particles. Using data from the FIELDS instruments aboard NASA’s Magnetospheric Multiscale satellites, the team identified a series of electromagnetic ion cyclotron waves—high-frequency oscillations that can be divided into several bands on the basis of their vibrational frequencies—within the plasma sheet boundary layer during a 3-day period in May of 2016.

    In addition to measuring multiple harmonics of these waves in the oxygen frequency band, the satellite instruments also unexpectedly detected other accompanying waves, including higher-frequency broadband and whistler mode chorus waves that modulate at the same frequency. By presenting the first simultaneous observations of these various wave types, this study is likely to open up an entirely new area of inquiry into cross-frequency wave interactions at both electron and ion scales.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

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

     
  • richardmitnick 1:25 pm on January 23, 2019 Permalink | Reply
    Tags: AGU, Ancient Faults Amplify Intraplate Earthquakes, , , , , Seismicity   

    From Eos: “Ancient Faults Amplify Intraplate Earthquakes” 

    From AGU
    Eos news bloc

    From Eos

    1.23.19
    Terri Cook

    A comparison of deformation rates from Canada’s Saint Lawrence Valley offers compelling evidence that strain in the region is concentrated along ancient structures from previous tectonic cycles.

    1
    A scientist sets up GPS equipment in Murray, Quebec. GPS measurements from Canada’s Saint Lawrence Valley may shed new light on the causes of poorly understood earthquakes that occur far from tectonic plate boundaries. Credit: Stephane Mazzotti

    Although earthquakes that strike in the interior of tectonic plates can inflict widespread damage, the processes that drive this type of seismicity are still poorly understood. This is partly due to the lower rates of deformation occurring in these regions compared to those at plate boundaries. Researchers have proposed that intraplate deformation is concentrated along ancient faults inherited from earlier cycles of tectonic activity. But exactly how these inherited structures influence modern seismicity remains a topic of vigorous debate.

    2
    Researchers installed GPS equipment in Havre-Saint-Pierre, Quebec, to help unravel the mechanics behind intraplate earthquakes. Credit: Stephane Mazzotti

    Now Tarayoun et al. [JGR Solid Earth] have quantified the impact of inherited structural features on the deformation occurring within eastern Canada’s Saint Lawrence Valley, a region that has experienced two full cycles of ocean basin inception and closure during the past 1.3 billion years. Using new episodic and continuous GPS data acquired from 143 stations, the team calculated surface deformation rates across the region and compared them to the rates predicted by models of glacial isostatic adjustment (GIA), the main process controlling deformation in the valley today.

    The results indicate that within the Saint Lawrence Platform—the geological province paralleling the Saint Lawrence River that is riddled with inherited, large-scale faults—the rates of deformation average 2 to 11 times higher than those measured in the surrounding provinces. And although the GPS-derived and GIA-predicted deformation rates generally agree in the surrounding provinces, the GPS-calculated rates are, on average, 14 times higher than those predicted by GIA models within the Saint Lawrence province. This result strongly suggests this zone of inherited structures concentrates modern surface deformation.

    This research offers compelling evidence that the Saint Lawrence Valley represents a zone of high intraplate deformation, controlled by forces linked to the region’s postglacial rebound and amplified by inherited structures from earlier tectonism. As the first study to quantify the impact of structural inheritance on surface deformation, this groundbreaking research will help unravel the processes that control deformation, as well as the poorly understood earthquakes that occur in the center of tectonic plates.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

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

     
  • richardmitnick 1:37 pm on August 31, 2018 Permalink | Reply
    Tags: "Earthquake Precursors, AGU, and Predictions, , , , Processes, ,   

    From Eos: “Earthquake Precursors, Processes, and Predictions “ 

    From AGU
    Eos news bloc

    From Eos

    8.31.18
    Dimitar Ouzounov

    A new book presents various studies that may establish a link between earthquakes and different types of precursor signals from the Earth, atmosphere and space.

    1
    The village of Onna was severely damaged in the 2009 earthquake that struck the Abruzzo region of Italy. Our goal is to find robust earthquake precursors that may be able to predict some of the most damaging events, like Onna. The proposed earthquake precursor signals described in our book could contribute to reliable forecasting of future seismic events; however, additional study and testing is needed. Credit: Angelo_Giordano / 170 images (CC0)

    Scientists know much more about what happens after an earthquake (e.g. fault geometry, slip rates, ground deformation) than the various and complex phenomena accompanying the preparatory phases before a seismic event. Pre-Earthquake Processes: A Multi-disciplinary Approach to Earthquake Prediction Studies, a new book just published by the American Geophysical Union, explores different signals that have been recorded prior to some earthquakes and the extent to which they might be used for forecasting or prediction.

    The reporting of physical phenomena observed before large earthquakes has a long history, with fogs, clouds, and animal behavior recorded since the days of Aristotle in Ancient Greece, Pliny in Ancient Rome, and multiple scholars in ancient China [Martinelli, 2018]. Many more recent case studies have suggested geophysical and geochemical “anomalies” occurring before earthquakes [Tributsch, 1978; Cicerone et al., 2009 Nature].

    It should not be surprising that a large accumulation of stress in the Earth’s crust would produce precursory signals. Some of these precursors have been correlated with a range of anomalous phenomena recorded both in the ground and in the atmosphere. These have been measured by variations in radon, the electromagnetic field, thermal infrared radiation, outgoing longwave radiation, and the total electron content of the ionosphere.

    Earth observations from sensors both in space and on the ground present new possibilities for investigating the build-up of stress within the Earth’s crust prior to earthquakes and monitoring a broad range of abnormal phenomena that may be connected. This could enable us to improve our understanding of the lead up to earthquakes at global scales by observing possible lithosphere-atmosphere coupling.

    For example, the French Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions (DEMETER) satellite mission (2004-2010) was the first to systematically study electro-magnetic signals in relation to earthquakes and volcanoes. Earlier in 2018, the China Seismo-Electromagnetic Satellite (CSES-1) was launched, dedicated to monitoring electromagnetic fields and particles. There is also a global initiative to develop and coordinate test sites for observation and validation of pre-earthquake signals located in Japan, Taiwan, Italy, Greece, China, Russia, and the United States of America.

    We have carried out statistical checks of historic data to study the correlations between precursor signals and major earthquake events. For example, a decadal study of statistical data for Japan and Taiwan suggested a significant increase in the probability of electromagnetic, thermal infrared, outgoing longwave radiation, and total electron content measurements before large earthquakes [Hattori and Han, 2018; Liu et al., 2018]. A study of satellite data from DEMETER for more than 9000 earthquakes indicated a decrease of the intensity of electromagnetic radiation prior to earthquakes with a magnitude greater than five [Píša et al. 2013, Parrot and Li, 2018]. These results suggest that the earthquake detection based on measurements of these variables is better than a random guess and could potentially be of use in forecasting.

    Our book also presents testing of the CN earthquake prediction algorithm for seismicity in Italy [Peresan, 2018], the first attempt of combining probabilistic seismicity models with precursory information [Shebalin, 2018], and the testing of short-term alerts based on a multi-parameter approach for major seismic events in Japan, Chile, Nepal and Iran [Ouzounov et al., 2018]. Further testing is needed to better understand false alarm ratios and the overall physics of earthquake preparation.

    2
    Conceptual diagram of an integrated satellite and terrestrial framework for multiparameter observations of pre‐earthquake signals in Japan. The ground component includes seismic, electro-magnetic observations, radon, weather, VLF–VHF radio frequencies, and ocean‐bottom electro-magnetic sensors. Satellite component includes GPS/total electron content, synthetic-aperture radar, Swarm, microwave, and thermal infrared satellites. Credit: Katsumi Hattori, presented in Ouzounov et al, 2018, Chapter 20

    Based on our international collaborative work, we found that reliable detection of pre-earthquake signals associated with major seismicity (magnitude greater than 6) could be done only by integration of space- and ground-based observations. However, a major challenge for using precursor signals for earthquake prediction is gathering data from a regional or global network of monitoring stations to a central location and conducting an analysis to determine if, based on previous measurements, they indicate an impending earthquake.

    We also found that no single existing method for precursor monitoring can provide reliable short-term forecasting on a regional or global scale, probably because of the diversity of geologic regions where seismic activity takes place and the complexity of earthquake processes.

    The pre-earthquake phenomena that we observe are intrinsically dynamic but new Earth observations and analytical information systems could enhance our ability to observe and better understand these phenomena.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

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

    Earthquake Alert

    1

    Earthquake Alert

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

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

    Get the app in the Google Play store.

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

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    The primary project partners include:

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

    The Earthquake Threat

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

    Part of the Solution

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

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

    System Goal

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

    Current Status

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

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

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

    Authorities

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

    For More Information

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

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

     
  • richardmitnick 2:22 pm on August 24, 2018 Permalink | Reply
    Tags: 3-D models of the North American continent on scales varying from urban to continental, AGU, , , , Geology in 3-D and the Evolving Future of Earth Science   

    From Eos: “Geology in 3-D and the Evolving Future of Earth Science” 

    From AGU
    Eos news bloc

    From Eos

    8.24.18
    O. S. Boyd
    L. H. Thorleifson

    1
    A new 3-D stratigraphic model of the subsurface of western Alberta in Canada. The uppermost surface represents the bedrock topography, and formations and groups of interest are shown in different colors. A speaker at a recent meeting on 3-D mapping discussed the modeling methods used to create this image. Credit: Alberta Geological Survey

    Last March, nearly 100 geoscientists from state, federal, academic, and private sector institutions in the United States and Canada gathered on the University of Minnesota campus. They presented current research on and discussed issues related to the latest developments in geologic mapping. They also discussed the synthesis of geological and geophysical information into 3-D models of the North American continent on scales varying from urban to continental.

    The geoscientists were concerned with mapping capabilities, from surficial materials to Precambrian basement, from young tectonic environments to well-established cratons, from water and mineral resources to natural hazards to basic science and education.

    In his opening plenary, Harvey Thorleifson of the University of Minnesota and the Minnesota Geological Survey briefly reviewed the history of 2-D geologic mapping from paper maps to Internet-accessible databases. He summarized scientific literature that highlighted enhanced data collection through digital capture of field data and the application of geoinformatics and 3-D methods to create maps. These advances have enabled the creation of models that contribute greatly to the science and planning of energy, minerals, water, hazards, and infrastructure design. These models are made possible by improved 3-D mapping that is well coordinated with spatial data infrastructure and well supported by global initiatives. Thorleifson suggested that geologic mapping is an essential service, part of a spectrum of activities that benefit society—from research and monitoring to modeling and resource management.

    Other presenters gave examples of the process to develop 3-D geological maps on various scales and the applications and benefits of this mapping:

    Kelsey MacCormack of the Alberta Geological Survey presented work on a 3-D geologic model of Alberta that is part of an effort to create a single source of geological information for the benefit of its diverse stakeholder groups (Figure 1).
    Don Sweetkind of the U.S. Geological Survey presented examples of regional groundwater systems, which require a regionally integrated 3-D geologic framework.
    Dick Berg of the Illinois State Geological Survey presented work on 3-D geologic mapping for urban areas, emphasizing the need to protect our local food and water supplies, as well as to help inform subsurface infrastructure.

    2
    Fig. 1. A spatial breakdown of 12 models that can be used to understand the structures that underly Alberta. The models, developed at a variety of scales, are helping researchers to understand geospatial relationships and interactions between the surface and subsurface. Credit: Alberta Geological Survey

    Attendees recognized the benefits of 3-D geologic mapping and the role that our interconnected electronic world can play to realize and maximize these benefits. They agreed that developing 3-D geologic products that are relevant, accessible, consistent, and readily updatable requires strong coordination among state, federal, academic, and industry partners, as well as a deep appreciation of the needs of potential users.

    Attendees were invigorated by the workshop and felt that the Geologic Mapping Forum should continue every 1–2 years and complement the annual Digital Mapping Techniques workshops held each year in late spring. A full workshop summary is available here.

    This meeting was hosted by the Minnesota Geological Survey.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

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

     
  • richardmitnick 10:07 am on August 17, 2018 Permalink | Reply
    Tags: AGU, Bhutan Earthquake Opens Doors to Geophysical Studies, , , , ,   

    From Eos: “Bhutan Earthquake Opens Doors to Geophysical Studies” 

    From AGU
    Eos news bloc

    From Eos

    13 August 2018
    György Hetényi
    Rodolphe Cattin
    Dowchu Drukpa

    1
    Taktsang, also known as the Tiger’s Nest, is a famous cliffside monastery in western Bhutan. Recent geophysical surveys have uncovered evidence of past earthquakes in this region that were much stronger than more recent events. Credit: iStock.com/KiltedArab

    In 2015, a magnitude 7.8 earthquake shook the Gorkha District of Nepal, killing more than 9,000. The memory of this event is still vivid for the residents of this central Himalayan nation.

    But farther east in the mountains, in Bhutan, many residents doubt the likelihood of a similar event happening to them. Bhutan had experienced several other earthquakes with a magnitude of about 6 during the past century. However, there was no clear evidence that Bhutan had ever seen an earthquake similar to the M7.8 Nepal event.

    Findings from recent geophysical exploration suggest that this confidence may be overly optimistic. These results have shown that the eastern Himalayas region is extremely complex compared with the rest of the mountain belt.

    The kingdom of Bhutan sets great store in its traditions and its principle of Gross National Happiness. Although its rugged terrain and remote location have allowed this kingdom to preserve its unique culture, these factors have also limited the development of international collaborations there, notably in the Earth sciences. This situation changed in 2009 after a damaging M6.1 earthquake that claimed 11 lives persuaded Bhutan to open its doors to exploration of the region’s geophysics.

    Our team studied mountain-building processes in this region after the 2009 earthquake. After 7 years of multipronged field campaigns, we learned that Bhutan’s geodynamics are as unique as its culture. The region’s crustal structure, seismicity, and deformation pattern are all different from what scientists had speculated previously.

    During our campaigns, we found evidence that at least one M8 earthquake had, in fact, occurred in Bhutan. This means that other earthquakes of this magnitude could occur in the region again [Hetényi et al., 2016b; Berthet et al., 2014; Le Roux-Mallouf et al., 2016].

    A Different Plate?

    Although the western and central Himalayan arc curves gently from Pakistan to Sikkim and has a low-lying foreland, the eastern third curves more sharply and has significant topographical relief south of the mountain belt, namely, the Shillong Plateau and neighboring hills (Figure 1). Previous studies proposed that these structures accommodate part of the India-Eurasia tectonic plate convergence. These earlier studies also proposed that the great 1897 Assam earthquake (M8.1) had relieved some of the strain between these converging tectonic plates, thereby lowering earthquake hazard in Bhutan.

    3
    Fig. 1. Topographic map of the 2,500-kilometer-long Himalayan arc and surrounding region, with formerly (yellow) and newly (pink) cataloged seismicity. The dextral fault zone (white arrows) between Sikkim and the Shillong Plateau marks the break of the India plate, east of which a zone of complex 3-D deformation begins. Red dates mark the three largest earthquakes mentioned in the text. Green lines mark the surface trace of the megathrust along which the India plate underthrusts the Himalayan orogen, as well as the thrust faults bounding the Shillong Plateau. Political boundaries are shown for reference. Abbreviations: Pl. = plateau; Pr. = Pradesh; Sik. = Sikkim.

    We collected new gravity, geodetic, and seismology data, and we found that the lithosphere—the rigid top layer of Earth—beneath Bhutan and the Shillong Plateau is most likely not part of the Indian plate or, if it once was, that it is now detached from it. The demarcation between plates stretches in a NW–SE direction, without a surface trace, but it is evident in a middle to lower crustal zone of continuously active seismicity and dextral (right-lateral) motion [Diehl et al., 2017]. This fault zone most likely hosted an M7 earthquake in 1930.

    4
    Research team member Théo Berthet monitors data collection during a campaign to a less visited region in central Bhutan. The Black Mountains, which rise to 4,500–4,600 meters, are visible in the background. Credit: György Hetényi

    Our GPS measurements confirm the relative motion of the newly defined microplate. These measurements also show that this microplate is rotating clockwise with respect to the Indian plate [Vernant et al., 2014]. The different behaviors of the two lithospheres are clearly expressed in their differences in flexural stiffness along the strike direction of the orogen (mountain belt). The flexural stiffness beneath Nepal is homogeneous [Berthet et al., 2013] but is comparatively weaker beneath Bhutan [Hammer et al., 2013].

    A similar, but less well defined, deep seismicity zone, with distinct GPS vectors and flexural signatures, may mark another terrain boundary farther east along the Himalayas in Arunachal Pradesh [Hetényi et al., 2016a].

    Not a Safe Haven

    India’s 1897 Assam earthquake, which occurred farther south, is only a few human generations in the past and has not completely faded from memory. No event since then has reached magnitude 7 in Bhutan, and many of the local population believe that big earthquakes cannot happen there.

    However, the return period of large Himalayan events is longer than oral history: Western Nepal, for example, has not experienced a significant event since 1505. It is true that over the past decades, the seismicity rate in Bhutan has been low, but we have found evidence of several great earthquakes in the past on the local megathrust.

    Geomorphological analysis of uplifted river terraces in central Bhutan revealed two major events over the past millennium [Berthet et al., 2014]. A newly excavated paleoseismological trench has documented surface rupture during a medieval event and a 17th–18th century event [Le Roux-Mallouf et al., 2016]. Calculations based on newly translated historical eyewitness reports, macroseismic information, and reassessed damage reports have constrained a M8 ± 0.5 earthquake on 4 May 1714 [Hetényi et al., 2016b].

    Thus, the seismic gap proved to be an information gap: The entire length of the Himalayas can generate earthquakes with a magnitude greater than 7.5, and it has done so in the past 500 years.

    5
    The landscape in eastern Bhutan, south of Trashigang, typically features incised valleys, steep slopes, and terraces. The hut in the center is shown in the inset for scale. The view here is to the east, and the hut is located at 27.2784°N, 91.4478°E. Credit: György Hetényi

    Differences at Multiple Scales

    The major change along the Himalayas occurs between their central western part (with a single convergence zone) and the eastern third (with distributed deformation including strike-slip motion), and the east–west extent of Bhutan exhibits even greater complexity. The crust appears to be smoothly descending in western Bhutan and is subhorizontal in the eastern part of the country [Singer et al., 2017a]. Our measurements of seismic wave speeds in the upper crust show important changes across the country, and they coincide well with the geological structure mapped at the surface [Singer et al., 2017b].

    The most striking difference between western and eastern Bhutan is the crustal deformation pattern. In the west, the accommodation of present-day crustal shortening is very similar to the rest of the Himalayas: The plates in the megathrust region are fully locked [Vernant et al., 2014], and microseismicity (the occurrence of small events) is scattered across the crust [Diehl et al., 2017]. In the east, the locked segment of the megathrust is shorter, and it focuses most of the microseismic activity within a smaller region. Also, the fault appears to be creeping (sliding without producing significant seismicity) in both shallower and deeper segments [Marechal et al., 2016].

    This variation of loading and background seismicity warrants further research along the entire Himalayan orogen because there is very little existing insight into variations of structures and processes at such short distance scales.

    6
    Gangkhar Puensum, a mountain in north central Bhutan, is clearly visible from the main road between Ura and Sengor, looking north-northwest. Gangkhar Puensum, at an altitude of 7,570 meters, is the highest unclimbed peak on Earth. For religious reasons, mountaineering above 6,000 meters is prohibited in Bhutan, so this record is very likely to remain. Credit: György Hetényi

    Bhutan Is Moving Forward

    Bhutan is an exotic place that has self-imposed isolation for a long time, but the country’s technology is now catching up at a rate that is higher than for the rest of the Himalayan regions. During our 2010 campaign, we used paper traveler’s checks, and we lacked individual cell phones. During our 2017 campaign, we had access to automated teller machines (ATMs) and 3G internet.

    Likewise, our 7 years of field campaigns in this region have advanced our geophysical exploration and geodynamic understanding considerably. Still, there is a strong need to continue and build on the existing knowledge, which includes freely available seismological, gravity, and GPS data from our projects.

    Focusing on three areas would help improve future development in Bhutan:

    Broadening timescales. Acquiring long-term data needed to confirm or to adjust interpretations made on relatively short timescales is possible only with national observatories. We have launched seismology and GPS monitoring initiatives, and we hope for long-term funding and training of local manpower for all levels of operation.
    Broadening investigations. Some fields of study have advanced dramatically, including work on glacial lake outburst floods and on landslides. Others, like seismic microzonation, have been limited so far and could benefit from more extensive efforts. There is also a strong need for up-to-date building codes that reflect the scientific knowledge coming from these investigations.
    Increasing public awareness of natural hazards. The Bhutanese Ministry of Home and Cultural Affairs now has a full department devoted to disaster management that includes well-trained employees and comprehensive administration. However, education is the key to reaching the broadest population possible, which requires regular adaptation of school curricula and concise, practical information that local residents from any generation can understand.

    We hope that recent efforts by our teams have promoted progress in the right direction. We also hope that large portions of the population will be sufficiently aware to deal with the next natural disaster. As our research shows, the next event may come sooner than previously thought.

    6
    The main Himalayan peaks in northwest Bhutan, on the border with southern Tibet, are, from left to right, Chomolhari, Jichu Drake, and Tserim Kang. Exact altitudes are debated, but Chomolhari is higher than 7,000 meters, and Tserim Kang towers above 6,500 meters. Credit: György Hetényi

    Acknowledgments

    The authors gratefully acknowledge all scientific, fieldwork, and logistical help provided by participants of the projects GANSSER and BHUTANEPAL, carried out in collaboration with the Department of Geology and Mines and the National Land Commission, Thimphu, Bhutan, and with support of Helvetas. Research highlighted in this article became possible thanks to the seed funding of the North-South Centre (ETH Zurich), followed by funding from the Swiss National Science Foundation (grants 200021_143467 and PP00P2_157627) and the French Agence Nationale de la Recherche (grant 13-BS06-0006-01).

    References

    Berthet, T., et al. (2013), Lateral uniformity of India plate strength over central and eastern Nepal, Geophys. J. Int., 195, 1,481–1,493, https://doi.org/10.1093/gji/ggt357.

    Berthet, T., et al. (2014), Active tectonics of the eastern Himalaya: New constraints from the first tectonic geomorphology study in southern Bhutan, Geology, 42, 427–430, https://doi.org/10.1130/G35162.1.

    Diehl, T., et al. (2017), Seismotectonics of Bhutan: Evidence for segmentation of the eastern Himalayas and link to foreland deformation, Earth Planet. Sci. Lett., 471, 54–64, https://doi.org/10.1016/j.epsl.2017.04.038.

    Hammer, P., et al. (2013), Flexure of the India plate underneath the Bhutan Himalaya, Geophys. Res. Lett., 40, 4,225–4,230, https://doi.org/10.1002/grl.50793.

    Hetényi, G., et al. (2016a), Segmentation of the Himalayas as revealed by arc-parallel gravity anomalies, Sci. Rep., 6, 33866, https://doi.org/10.1038/srep33866.

    Hetényi, G., et al. (2016b), Joint approach combining damage and paleoseismology observations constrains the 1714 A.D. Bhutan earthquake at magnitude 8±0.5, Geophys. Res. Lett., 43, 10,695–10,702, https://doi.org/10.1002/2016GL071033.

    Le Roux-Mallouf, R., et al. (2016), First paleoseismic evidence for great surface-rupturing earthquakes in the Bhutan Himalayas, J. Geophys. Res. Solid Earth, 121, 7,271–7,283, https://doi.org/10.1002/2015JB012733.

    Marechal, A., et al. (2016), Evidence of interseismic coupling variations along the Bhutan Himalayan arc from new GPS data, Geophys. Res. Lett., 43, 12,399–12,406, https://doi.org/10.1002/2016GL071163.

    Singer, J., et al. (2017a), The underthrusting Indian crust and its role in collision dynamics of the eastern Himalaya in Bhutan: Insights from receiver function imaging, J. Geophys. Res. Solid Earth, 122, 1,152–1,178, https://doi.org/10.1002/2016JB013337.

    Singer, J., et al. (2017b), Along-strike variations in the Himalayan orogenic wedge structure in Bhutan from ambient seismic noise tomography, Geochem. Geophys. Geosyst., 18, 1,483–1,498, https://doi.org/10.1002/2016GC006742.

    Vernant, P., et al. (2014), Clockwise rotation of the Brahmaputra Valley relative to India: Tectonic convergence in the eastern Himalaya, Naga Hills, and Shillong Plateau, J. Geophys. Res. Solid Earth, 119, 6,558–6,571, https://doi.org/10.1002/2014JB011196.

    Author Information

    György Hetényi (email: gyorgy.hetenyi@unil.ch), Faculty of Geosciences and Environment, Institute of Earth Sciences, University of Lausanne, Switzerland; Rodolphe Cattin, Géosciences Montpellier, University of Montpellier, France; and Dowchu Drukpa, Department of Geology and Mines, Ministry of Economic Affairs, Thimphu, Bhutan

    See the full article here .

    Earthquake Alert

    1

    Earthquake Alert

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

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

    Get the app in the Google Play store.

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

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    The primary project partners include:

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

    The Earthquake Threat

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

    Part of the Solution

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

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

    System Goal

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

    Current Status

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

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

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

    Authorities

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

    For More Information

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

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

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

     
  • richardmitnick 11:33 am on August 3, 2018 Permalink | Reply
    Tags: AGU, , Two Active Volcanoes in Japan May Share a Magma Source,   

    From Eos: “Two Active Volcanoes in Japan May Share a Magma Source” 

    From AGU
    Eos news bloc

    From Eos

    31 July 2018
    Kimberly M. S. Cartier

    Evidence collected following the 2011 eruption of Japan’s Shinmoedake volcano suggests that the powerful event affected the behavior of an active caldera nearby.

    1
    Japan’s Shinmoedake volcano on the island of Kyushu, erupting on 27 January 2011. Credit: Kyodo via AP Images

    A single magma reservoir deep beneath Japan’s Kyushu Island may feed two of its most active volcanoes. GPS measurements of Aira caldera show that its once steady inflation stalled while the nearby Shinmoedake volcano erupted in early 2011 and then resumed when the eruption stopped. This suggests that the two volcanic areas draw from a common magma source deep under Kyushu and that the two areas may interact before, during, and after eruptions.

    “We observed a radical change in the behavior of Aira before and after the eruption of its neighbor,” Elodie Brothelande, lead scientist on the study and a postdoctoral researcher at the Rosenstiel School of Marine and Atmospheric Science at the University of Miami in Florida, said in a press release. “The only way to explain this interaction is the existence of a connection between the two plumbing systems of the volcanoes at depth,” she said.

    Observations of interconnected volcanic systems like this one are rare, so finding and studying them may help forecasters improve their eruption prediction and hazard models, Brothelande told Eos. Her team published its results in late June in the journal Scientific Reports.

    An Underground Connection

    Shinmoedake, which is part of the Kirishima volcanic group in southwestern Japan, began erupting in January 2011 and released more than 20 million tons of magma, ash, and pyroclastic rock. Watch a snippet of this eruption in the video below.

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    https://www.sciencedirect.com/science/article/pii/S037702731300111X

    To probe the possible connection between Shinmoedake and Aira, the researchers measured the vertical and horizontal displacements of the land in and around Aira caldera. They gathered daily GPS data from 32 stations in Kyushu spanning 2009–2013, 2 years before and after the Shinmoedake eruption. With these data, they calculated how Aira swelled and deflated in the time surrounding the eruption.

    The researchers compared the caldera’s behavior to models of how it would have reacted had it been responding only to geologic stress caused by Shinmoedake erupting. They found that Aira’s behavior was inconsistent with having geologic stress as the primary cause: Its pattern of inflation and deflation was wrong, and the amount it deflated didn’t match predictions.

    However, the models showed that an underground magma reservoir in the mantle feeding both volcanoes could explain the caldera’s behavior during the nearby eruption. Brothelande said that Aira and Shinmoedake are “good candidates” for this type of connection because they share the same active fault block and are relatively close to each other.

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    Lava forms ropey pāhoehoe textures. How molten must the subsurface rock that fueled this lava be to get classified as “magma”? Credit: iStock.com/Justin Reznick
    By Allen F. Glazner, John M. Bartley, and Drew S. Coleman 22 September 2016.

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    Satellite image of southern Kyushu on 3 February 2011 during an eruption of Shinmoedake. The two areas compared in this study, the Kirishima volcanic group and Aira caldera, are circled. The volcanoes at the foci of the research, Shinmoedake and Sakurajima, are marked by triangles. Credit: NASA

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    Basaltic lava erupting from an active parasitic cone (about 5 meters tall) on the side of Puʻu ʻŌʻō, Hawaii, 1997. The flowing material is unquestionably erupted magma, but whether its partially molten source region should be called magma is debatable. Credit: Allen Glazner

    Here’s how that scenario would have worked: In the period before Shinmoedake’s eruption, the magma reservoir inflated both volcanoes. The eruption then rapidly drew magma up from the reservoir and caused a sudden drop in pressure underground. The reservoir, in turn, drew magma from Aira in response to the pressure drop, causing the observed caldera deflation. Once Shinmoedake finished erupting, the magma reservoir resumed filling both volcanoes.

    A Promising Step

    “When a volcano enters a period of unrest or eruption, a common concern from communities and media is the chance of a neighboring volcano being ‘triggered,’” said Janine Krippner, a volcanologist and postdoctoral researcher at Concord University in Athens, W.Va., who was not involved with the project.

    “Research into the relationships between neighboring volcanic systems is important, but it is rare that evidence is found for systems affecting one another,” she said. “This study is a step in the direction of understanding any links between neighboring volcanic systems.”

    Although the research is very promising, more evidence is needed to solidify the ties between the two volcanoes, Krippner added. For example, repeat observations of the volcanoes during the time before and after an eruption, as well as geochemical analysis of the pair’s eruption products, could help. “I would expect to see similarities in geochemistry trends—the magma ‘genetics’—in eruption products like lavas, volcanic ash, and pyroclastic deposits if they have a common source,” she said.

    Past geochemical [Journal of Volcanology and Geothermal Research] studies have shown that eruption products from the two volcanic systems have similar isotope ratios for strontium and neodymium, the paper notes. However, Brothelande told Eos, a “real comparative study is still required” to geochemically link Shinmoedake and Aira to a common source.

    Shinmoedake and Aira’s associated volcanic peak, Sakurajima, erupted in 2017, and each has seen ongoing intermittent activity throughout 2018. The research team is planning to study the activity at Shinmoedake and Aira from the past 2 years to better understand their underground connection.

    Brothelande pointed out that there are other volcanic systems in which similar hidden connections may cause a volcano to interact with its neighbor, for example, in Hawaii, Alaska, and Italy. This occurs even in smaller systems of lava domes and maars like those in France and Colorado. Models that calculate eruption probabilities, she said, likely need to include these interactions.

    “External factors that have an impact on volcanic eruptions—triggering or delaying—have been neglected for a long time,” Brothelande said. But the findings at Shinmoedake and Aira open a new door, she added. “Nearby eruptions have to be included as well.”

    See the full article here .

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