Floods and Quakes: Could there be a connection? Some geophysicists think so

Salton Sea

Important Takeaways:

  • Floods linked to San Andreas quakes
  • Historical record underscores connections between reservoirs and seismic activity.
  • Geophysicists have linked historical earthquakes on the southern section of California’s famed San Andreas fault to ancient floods from the nearby Colorado River.
  • The work has broad implications for understanding how floods or reservoirs relate to quakes — a topic that gained new relevance in 2008, after a massive earthquake in China’s Sichuan province killed more than 80,000 people. Some geologists have proposed that impounding water behind a newly built dam there helped hasten the quake.
  • Now, new work in southern California suggests that at least three times in the past 2,000 years, the weight of river water spreading across floodplains seems to have helped trigger earthquakes in the region.
  • The team subsequently analyzed data from 20-metre-deep cores pulled from the lake bed in 2003 during earlier work for the US Bureau of Reclamation. The cores showed layers of coarse sandy material laid down during floods — at the same time that seismic activity was known to have occurred.
  • “We found quakes happened about every 100 to 200 years and were correlated with floods,” says Brothers. “The Colorado River spills, loads the crust and then there is a rupture.” He says the team is “very confident” in its evidence for the existence of three flood-derived quakes, of roughly magnitude 6, which happened about 600 years ago, 1,100 years ago and 1,200–1,900 years ago. “Sediments don’t lie,” he says.
  • A quake of about magnitude 7 struck the southern San Andreas fault about 300 years ago; the next is a century overdue. One possible reason is the Hoover Dam: since its completion in 1936, the lower Colorado no longer floods.

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Congress requests new map showing where damaging earthquakes are most likely to occur

new-usgs-map

Important Takeaways:

  • Nearly 75% of the U.S. could experience damaging earthquake shaking, according to a recent U.S. Geological Survey-led team of more than 50 scientists and engineers.
  • This was one of several key findings from the latest USGS National Seismic Hazard Model (NSHM). The model was used to create a color-coded map that pinpoints where damaging earthquakes are most likely to occur based on insights from seismic studies, historical geologic data, and the latest data-collection technologies.
  • The congressionally requested NSHM update was created as an essential tool to help engineers and others mitigate how earthquakes affect the most vulnerable communities by showing likely earthquake locations and how much shaking they might produce. New tools and technology identified nearly 500 additional faults that could produce a damaging quake, showcasing the evolving landscape of earthquake research.
  • Key findings from the updated seismic hazard model include:
    • Risk to people: Nearly 75% of the U.S. could experience potentially damaging earthquakes and intense ground shaking, putting hundreds of millions of people at risk.
    • Widespread hazard: 37 U.S. states have experienced earthquakes exceeding magnitude 5 during the last 200 years, highlighting a long history of seismic activity across this country.
    • Structural implications: The updated model will inform the future of building and structural design, offering critical insights for architects, engineers, and policymakers on how structures are planned and constructed across the U.S.
    • Unified approach: This marks the first National Seismic Hazard Model to encompass all 50 states simultaneously, reflecting a massive collaborative effort with federal, state, and local partners.
    • Not a prediction: No one can predict earthquakes. However, by investigating faults and past quakes, scientists can better assess the likelihood of future earthquakes and how intense their shaking might be

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In Iceland as earthquakes dwindle into the hundreds experts are wary to say it’s over

Iceland-Earthquakes

Important Takeaways:

  • Iceland Volcano Update: Eruption Map, Experts’ Views ‘Completely Changed’
  • In an update on Tuesday, the Icelandic Meteorological Office said that the Reykjanes Peninsula—where an eruption was thought likely after a burst of seismic activity from November 10—would be subject to increased monitoring and more experts drafted in to help.
  • On Wednesday, the Icelandic Met Office said the ground around Svartsengi “continues to inflate,” meaning “further dikes or an eruption remain possible.” While the area the previous dike formed is anticipated to be the most likely area of eruption, experts have not been able to discount the possibility that magma propagates elsewhere in the region.
  • Between 1,500 and 1,800 earthquakes a day were being recorded from November 10 for nearly two weeks, before dropping to the low hundreds. Between 200-300 earthquakes have been registered a day in the past two days, while the Icelandic Met Office said as of 6:15 a.m. ET on Wednesday there had so far been a hundred.
  • While the intense seismic activity around the vertical dike appears to have subsided for the time being, the continued flow of lava into the horizontal intrusion means another could form, or more magma flow into the dike, without warning.

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Iceland Volcano: Number of earthquakes drops to a couple hundred a day from a thousand, but experts think it may not be over

Many-earthquakes-Iceland

Important Takeaways:

  • Iceland Volcano Update: Eruption-Making Magma Shift May Be ‘Days’ Away
  • Another upward shift of magma through the Earth’s crust under Iceland that has the potential to cause an eruption “could happen in the next few days or possibly after several months,” as officials have expressed “considerable” uncertainty as to when the next volcanic episode might occur.
  • Last week, a decline in the number and severity of earthquakes around the magma intrusion led it to conclude that an eruption from the episode was less likely but still possible. However, experts have warned that volcanic activity in the region could pick up again.
  • Between 1,500 and 1,800 earthquakes a day were being recorded from November 10 for nearly two weeks, before dropping to the low hundreds.
  • The earthquakes have mostly occurred over and around the site of the magma dike—which is estimated to be around 9.3 miles long and runs alongside the coastal fishing town of Grindavik, on a southwesterly peninsula on Iceland’s main island.
  • A sudden shift in the North American tectonic plate away from the Eurasian plate is thought to have allowed magma to suddenly push upwards through a rift that runs between the two of them under Iceland.
  • One Icelandic volcanologist previously told Newsweek that while the volcanic episode may have ended, it may mark the start of an “intense” period of tectonic activity based on historic trends.
  • “We know that this is not the end of activity on the Reykjanes peninsula”

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Likelihood of Iceland Volcano eruption remains high with 1,700 earthquakes in 24 hours

Iceland-Volcano

Important Takeaways:

    • The heightened seismic activity, which started more than a week ago within the Reykjanes Peninsula, continued into Saturday with approximately 1,700 earthquakes recorded in 24 hours, according to the Icelandic Meteorological Office.
    • The office noted a high likelihood of volcanic eruption continues in the southwest along a 9-mile magma tunnel, with the highest likelihood of an eruption starting north of the small fishing town of Grindavík, which has a population of 3,400 and is located near Hagafell mountain
    • Grindavík’s residents evacuated from the town last week before the chance to briefly re-enter on Thursday and Friday to collect important belongings, according to NBC…
    • A volcanic eruption could disrupt air travel in other countries if it’s large enough. The 2010 eruption of Iceland’s Eyjafjallajökull volcano created massive plumes of ash that were swept into Europe by northerly winds, canceling more than 100,000 flights and creating $1.7 billion in lost revenue to airlines.

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Latest Iceland Rumbling: 23,000 Earthquakes since October in an area with an estimated 130 volcanos

Important Takeaways:

  • 23,000 Earthquakes in Just Weeks Raise Fears of Volcanic Eruption
  • Iceland has recorded thousands of earthquakes, localized in the Reykjanes Peninsula, in recent days, with the Nordic country evacuating its famous Blue Lagoon geothermal spa amid fears of a possible volcanic eruption.
  • The effects of the recent earthquakes were felt as far as Borgarnes town, 51 kilometers (~32 miles) away from the peninsula. The Icelandic Meteorological Office (IMO) has documented more than 23,000 tremors since October, including an earthquake of magnitude 5.0 on November 2nd, the largest spike in activity since tremors began.
  • The Reykjanes Peninsula laid dormant for an estimated 800 years before an eruption in 2021. There are around 130 volcanoes across the island nation, most of which are active.

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Cluster of earthquakes under Mount St. Helens has some concerned that it’s recharging

StHelens-quakes

Important Takeaways:

  • 400 earthquakes recorded under Mount St. Helens since mid-July
  • Scientist says small quakes signal volcano is ‘recharging’
  • About 400 earthquakes have rumbled under Mount St. Helens since mid-July, the largest chain of shakes since the volcano finished erupting in 2008, the U.S. Geological Survey reported last week.
  • Small magnitude earthquakes, detected only by sensitive equipment, signal a volcano’s “recharging” as magma flows through chambers and cracks deep under the ground, said Wes Thelen, U.S. Geological Survey Cascades Volcano Observatory geophysicist and seismologist.
  • Between late August and early September, scientists observed 40 to 50 earthquakes per week located between 2.5 to 5 miles below the crater floor, before recently dwindling to 30. To compare, Mount St. Helens averaged roughly 11 quakes per month since 2008.

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Recent earthquakes near volcanoes Global report

Volcano-Report-10.10.23

Important Takeaways:

  • Clear Lake volcano (California): 12 earthquakes up to magnitude 1.7
  • Fagradalsfjall volcano (Reykjanes Peninsula, Iceland): 11 earthquakes up to magnitude 1.0
  • Katla volcano (Iceland): 8 earthquakes up to magnitude 2.4
  • Kilauea volcano (Hawai’i (Big Island)): 13 earthquakes up to magnitude 2.4
  • Mauna Kea volcano (Hawai’i (Big Island)): magnitude 2.3 earthquake
  • Tenerife volcano (Canary Islands): 2 earthquakes up to magnitude 3.0
  • Rincón de la Vieja volcano (Costa Rica): magnitude 3.7 earthquake
  • Tenorio volcano (Costa Rica): 2 earthquakes up to magnitude 3.4
  • Tambora volcano (Sumbawa): magnitude 3.3 earthquake
  • Barva volcano (Costa Rica): magnitude 3.0 earthquake
  • Ontake-san volcano (Honshu): magnitude 2.9 earthquake
  • Hulubelu volcano (Sumatra): magnitude 2.5 earthquake
  • Herdubreid volcano (Iceland): 2 earthquakes up to magnitude 2.3
  • Chinameca volcano (El Salvador): magnitude 2.1 earthquake

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Even with years of earthquake research there’re still many questions of when, where and how strong the next major quake will occur

Earthquake-Nightmare

Important Takeaways:

  • Earthquakes Are a Special Kind of Nightmare
  • There is something uniquely nightmarish about major earthquakes that strike under or close to villages, towns, and cities
  • Tragedies born of geologic forces can be simultaneously extreme and swift. Volcanic eruptions can produce rivers of scorching gas, ash, and debris that move at breathtaking speed, igniting and scouring anything in their path. Tsunamis—caused by the dramatic twitching of tectonic plates and their faults, or by immense landslides, or by volcanic explosions—can, and have, effortlessly swept entire towns and villages aside in a matter of minutes.
  • The essentially immediate, invisible arrival of an earthquake is almost supernatural. Science tells us that earthquakes arise from the sudden release of energy accumulated over years, decades, or centuries.
  • A tsunami voyaging quickly across the ocean will set off alarms in distant countries, giving those who receive the warning some time to flee or brace themselves.
  • Volcanoes usually give off warning signs hours, days, sometimes even months or years in advance that an eruption is likely on its way.
  • But we currently do not have any way to know when the next significant earthquake will strike, precisely where it will strike, how powerful it will be, how much shaking it will cause, or what kind of damage it will do.

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South East of the Philippines Mayon Volcano increased in volcanic earthquakes; Officials maintain Alert level 3

Mayon Volcano

Luke 21:11 There will be great earthquakes, and in various places famines and pestilences. And there will be terrors and great signs from heaven.

Important Takeaways:

  • PHIVOLCS: Mayon volcanic earthquakes up, lava flows ‘bulked up’
  • Slow effusion of lava from Mayon Volcano’s crater continued to feed and bulk up established lava flows amid an increase in volcanic earthquakes, the Philippine Institute of Volcanology and Seismology (PHIVOLCS) said Wednesday.
  • “Respectively, these lava flows have maintained distal lengths of approximately 2.8 kilometers, 2.4 kilometers and 600 meters from the crater,” it said.
  • PHIVOLCS also recorded 304 volcanic earthquakes and 137 rockfall events over the past 24 hours. The number of volcanic earthquakes was higher compared to the 267 recorded the previous day.
  • Three pyroclastic density currents (PDCs) and 30 ashing events that lasted 20 to 40 seconds were also recorded.
  • “The combined seismic energy release of these, however, has not increased beyond the trend of effusive activity,” PHIVOLCS said.
  • “Alert Level 3 is maintained over Mayon Volcano, which means that it is currently in a relatively high level of unrest as magma is at the crater and hazardous eruption within weeks or even days is possible,” PHIVOLCS said.

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