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  • richardmitnick 11:45 pm on May 5, 2018 Permalink | Reply
    Tags: , , , , , Volcanology   

    From temblor: “Pele, the Hawai’i Goddess of Fire, Lightening, Wind, and Volcanoes” 

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    From temblor

    May 5, 2018
    Jason R. Patton, Ph.D.
    Ross Stein, Ph.D.
    Volkan Sevilgen, M.Sc.

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    At 12:46 p.m. HST, a column of robust, reddish-brown ash plume occurred after a magnitude 6.9 South Flank of Kïlauea earthquake shook the Big Island of Hawai‘i. (USGS HVO)

    Hawai’i Earthquakes and Eruptions

    Over the past week there has been a flurry of earthquake activity on the Big Island of Hawai’i. These earthquakes are related to the volcanic activity associated with Kïlauea magmatism. As magma rises and moves within the magma chamber, we can infer the motion direction and velocity as earthquakes respond to these changes in magma pressure. At the time we write this, there have been over 900 shallow depth earthquakes reported on the U.S. Geological Survey earthquake website.

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    Hawai’i as seen in Google Earth, 3X vertical exaggeration. One week of earthquakes from USGS (orange dots)

    Below is a map that shows seismicity from the past week. Blue circles are located relative to the Pu’u ‘Ō’ō-Kupaianaha Volcano April 30 activity and the May 3 and May 4 fissure eruptions near the Leilani Estates (a residential subdivision near Pāhoa, Hawai’i). This area was evacuated and nobody was harmed. Several buildings were destroyed by fire. The seismicity also initially followed this eastward trend in motion. Initially, earthquakes were located to the west, but migrated to the east prior to the fissure eruptions. In addition, the lava lake formed in late April dropped in elevation prior to the fissure eruption (possibly due to the migration of magma from west to east). However, later seismicity migrated back to the west. This may be due to the changes in pressure associated with magma movement.

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    Temblor map showing earthquakes, faults, and shaded topography.

    Hawai’ian Hotspot Volcanism

    The Hawai’ian Islands are part of a chain of volcanoes and seamounts that are formed as the oceanic Pacific plate moves over a magmatic hotspot. This hotspot is a region where there exists a plume of upwelling magma that erupts through the Pacific plate to form volcanic eruptions. Over time, as the plate moves, the older volcanoes get further away from the hotspot. The most recent and currently volcanically active part of the Hawai’ian Islands is located on the Big Island of Hawai’i, where the Kïlauea volcano is located. Below is a visualization of how the magma chamber below Kïlauea may be oriented. Note how the magma plume rises to the Kïlauea Caldera, then spreads laterally to feed additional volcanic centers along the rift zones.

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    Cut away view looking beneath Kïlauea Volcano (USGS, 2010).

    Hawai’ian Tectonics, Seismicity, and Eruptions

    There are three main sources of earthquakes in Hawai’i: magmatic, volcanic edifice, and deep tectonic (IRIS). Magmatic earthquakes occur when magma rises or moves within the crust. As the magma rises beneath the volcanoes it can break up the crust. Changes in pressure and volume in the magma and volcano can increase the stress on faults in the region causing earthquakes.

    There are faults within the volcanic edifice (the cone shaped structure that forms the shape of the volcano), as well as faults that exist beneath the volcano, between the volcano and the underlying Pacific plate. These faults can be sources of earthquakes independent of volcanism. Earthquakes in the volcanic edifice are extensional and caused by gravitational collapse of the volcanic rocks that form the edifice. These earthquakes tend to be small, with maximum magnitudes in the M 5 range. These extensional earthquakes may trigger earthquakes on the fault formed beneath the volcano. Earthquakes along this fault system can be much larger, including a M 7.9 Ka’u earthquake in 1868. A more recent example is the November 29, 1975 M 7.1 earthquake that happened near the current seismic and volcanic activity.

    Earthquakes can occur within both the upper brittle mantle and oceanic crust as changes in pressure and temperature are exerted by the overlying volcano. The October 15, 2006 Kiholo Bay earthquake is an example of this type of earthquake. These are deeper than the other earthquakes, are further away from people and cause lesser shaking, for the same magnitude, than for shallower magmatic and volcanic edifice earthquakes.

    The major fault systems on the southern part of the Big Island include rift zones and normal faults formed by extension either from gravitational collapse or extension related to the rift zones. The East Rift Zone and the Hilina fault appear to be the likely fault systems associated with this ongoing seismic activity. The 1975 earthquake may be a good analog to the current seismicity because it was also associated with magma injection.

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    Map showing the major volcanic centers, rift zones, and fault systems in Hawai’I (USGS, 2010).

    The current sequence of earthquakes began near the Pu’u ‘Ō’ō-Kupaianaha Volcano, where there is a crater formed from prior eruptions. This crater was filled with lava and the lava level reached the rim of the crater and overflowed the crater on 4/30/2018.

    Tsunami

    The 1975 M 7.1 earthquake generated a tsunami observed by tide gages located in Maui, Kauai, Hawai’i, and Oahu. Wave heights were up to several feet in Hilo and several inches high in Oahu. This tsunami was too small to have an impact elsewhere. The M 6.9 earthquake also generated a tsunami, but it was smaller than the 1975 tsunami. The Hilo tide gage shows a wave height of less than a foot (amplitude = 0.399 meter).

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    Water surface elevation data from Hilo, Hawai’i from IOC.

    What is Next?

    Using the 1975 earthquake as an analogy, the M 6.9 earthquake is possibly the main shock in this sequence. However, our historic record is only about 200 years long and we may not have enough knowledge to fully understand the entire range of possible outcomes. In terms of volcanism, this part of Hawai’i has eruptions on an almost ongoing basis. Below is a figure that shows the volcanic activity since 1780. Note that the USGS considers that we are currently in a period of continuous activity.

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    Graph summarizing the eruptions of Mauna Loa and Kïlauea Volcanoes during the past 200 years (USGS, 2010).

    Here is another great map showing the relative volcanic hazard for the areas around the Big Island of Hawai’i. Severity of volcanic hazard is represented by color. The gray areas show regions where lava flows have happened in the past ~200 years. Note that the rift zones of Kïlauea are considered a region of increased volcanic hazard. So, if one resides or visits to regions of increasing severity of hazard, be prepared to respond to volcanic and seismic activity. Be prepared and know your hazard!

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    Map of Island of Hawai‘i showing the volcanic hazards from lava flows (USGS, 2010).

    References

    IRIS, Hawai’ian Islands: Origins of Earthquakes https://www.iris.edu/hq/inclass/animation/Hawai’ian_islands_origin_of_earthquakes
    USGS, 2010. Eruptions of Hawaiian Volcanoes—Past, Present, and Future, U.S. Geological Survey, General Information Product 117, 72 pp.
    Ando, M., 1979. The Hawaii Earthquake of November 29, 1975: Low Dip Angle Faulting Due to Forceful Injection of Magma in JGR, v. 84, no. B13
    IOC Sea Level Station Monitoring Facility http://www.ioc-sealevelmonitoring.org/index.php
    USGS HVO, Hawaiian Volcano Observatory https://volcanoes.usgs.gov/volcanoes/kilauea/
    Additional background material can be found here: http://earthjay.com/?p=7350

    See the full article here .

    Please help promote STEM in your local schools.

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    Stem Education Coalition

    Earthquake Alert

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    Earthquake Alert

    Earthquake Network project

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

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

    Get the app in the Google Play store.

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    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

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    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 9:18 am on April 5, 2018 Permalink | Reply
    Tags: Eruption of Stromboli (animated), , Mauna Ulu eruption – a spectacular outpour of lava that lasted for a total of 1774 days, , The Halemaumau crater is at the peak of Kilauea, This Volcano Erupted For 5 Years Straight and The Photos Are Mesmerising, Volcanology, You're looking at a very rare type of lava fountain   

    From Science Alert: “This Volcano Erupted For 5 Years Straight, And The Photos Are Mesmerising” 

    ScienceAlert

    Science Alert

    5 APR 2018
    SIGNE DEAN

    You’re looking at a very rare type of lava fountain.

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    (USGS)

    On 24 May 1969, a deep rumbling started within Kīlauea, the largest of the volcanoes comprising the island of Hawai’i.

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    Looking up the slope of Kilauea, a shield volcano on the island of Hawaii. In the foreground, the Puu Oo vent has erupted fluid lava to the left. The Halemaumau crater is at the peak of Kilauea, visible here as a rising vapor column in the background. The peak behind the vapor column is Mauna Loa, a volcano that is separate from Kilauea.
    Date 17 October 2011, 00:57 (UTC)
    Source Puu_Oo_looking_up_Kilauea.jpg

    Those were the first moments of the historical Mauna Ulu eruption – a spectacular outpour of lava that lasted for a total of 1,774 days, at the time becoming the longest Kīlauea eruption in at least two millennia. Staff at the Hawaiian Volcano Observatory had noted that the magma reservoir underneath the tip of the volcano had started to swell, but they still didn’t expect the magnificent activity that lasted well into the summer of 1974.

    So huge was this eruption that the cooling lava created a whole new landscape on the side of Kīlauea, earning the name of “growing mountain”, or Mauna Ulu. In 1969 alone, twelve huge lava fountains erupted at the site, and much of this activity has been captured for posterity in glorious photographs. The United States Geological Survey (USGS) recently reminded the world of the Mauna Ulu eruption with a throwback photo to one of the rarest types of a lava fountain you can possibly get.

    Usually, lava just explodes all over the place without any rhyme or reason, making this beautiful, perfectly rounded dome fountain all the more special. (By the way, the foreground is not the ocean, as it might seem at first glance – it’s a landscape of cooled lava.)

    Lava fountains, in all their blazing glory of raw exploding geology, can reach the dizzying heights of 500 metres, according to USGS. They typically happen when lava shoots out of an isolated vent or a fissure in the volcano, or when water in a confined space gets inside a lava tube.

    On June 25 of the same year, a massive 220-metre (722-foot) fountain of lava shot up from the volcano:

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    (USGS)

    On August 15, there was this little splatter of boiling hot rock, just 8 metres (26 feet) high but shaped rather like a searing mushroom cloud. At that point in the eruption, activity like this was almost constantly happening at Mauna Ulu:

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    (USGS)

    One of the most spectacular events during the eruption were these 100-metre high ‘lava falls’ overflowing the ‘Alae Crater on Kīlauea, on August 5. “For the two seasoned observers who witnessed this awe-inspiring event, nothing else matched it during the entire Mauna Ulu eruption,” USGS writes on their website.

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    (USGS)

    Even after that stunning event, Kīlauea was far from done inspiring awe in its observers. Another massive lava fountain shot up in the air on October 20, and in this photo you can even see a geologist standing on a viewing platform about 800 metres (2,625 feet) away. Despite the considerable distance, observers still had to hide behind a stone wall as the heat was so intense – sometimes dry grass right next to the platform would even catch fire.

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    (USGS)

    Of course, Kīlauea is far from done. Only nine years later, the Pu’u ‘Ō’ō eruption began – and it is still active today, producing regular spectacles of lava explosions. What’s particularly crazy is that’s not even the longest continually active volcano on our planet. According to Guinness World Records, this honour belongs to Mt Stromboli in Italy.

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    Eruption of Stromboli (animated)
    Date 15 May 2012
    Author Jens Bludau

    You can see the full gallery of the Mauna Ulu eruption on the USGS website.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

     
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