Category: Seismic Activity


Fracking-linked earthquakes likely to worsen – seismologists

Published time: May 02, 2014 03:40

David McNew / Getty Images / AFP

David McNew / Getty Images / AFP

Ongoing hydraulic fracking operations will only exacerbate seismic activity, leading to heightened earthquakes in areas where wastewater is injected deep underground, according to new research.

To unleash natural gas, hydraulic fracturing – or fracking – requires large volumes of water, sand, and chemicals to be pumped underground. Scientists attending the Seismological Society of America (SSA) annual meeting said Thursday that this storage of wastewater in wells deep below the earth’s surface, in addition to fracking’s other processes, is changing the stress on existing faults, which could mean more frequent and larger quakes in the future.

Researchers previously believed quakes that resulted from fracking could not exceed a magnitude of 5.0, though stronger seismic events were recorded in 2011 around two heavily drilled areas in Colorado and Oklahoma.

“This demonstrates there is a significant hazard,” said Justin Rubinstein, a research geophysicist at the US Geological Survey (USGS), according to TIME magazine. “We need to address ongoing seismicity.”

Not all of the more than 30,000 fracking disposal wells are linked to quakes, but an accumulating body of evidence associates an uptick in seismic activity to fracking developments amid the current domestic energy boom.

The amount of toxic wastewater injected into the ground seems to provide some clarity as to what causes the earthquakes. A single fracking operation uses two to five million gallons of water, according to reports, but much more wastewater ends up in a disposal well.

 

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By Reuters

Earthquakes rattled residents in Oklahoma on Saturday, the latest in a series that have put the state on track for record quake activity this year, which some seismologists say may be tied to oil and gas exploration.

One earthquake recorded at 3.8 magnitude by the U.S. Geological Survey rocked houses in several communities around central Oklahoma at 7:42 a.m. local time.

Another about two hours earlier in the same part of the state, north of Oklahoma City, was recorded at 2.9 magnitude, USGS said.

Root issue: Seismologists believe the quakes may be tied to oil and gas exploration

Root issue: Seismologists believe the quakes may be tied to oil and gas exploration

 

Those two were preceded by two more, at 2.6 magnitude, and 2.5 magnitude, that also rolled the landscape in central Oklahoma early Saturday morning.

A 3.0 magnitude tremor struck late Friday night in that area as well, following a 3.4 magnitude hit Friday afternoon.

The quakes have set record levels of seismic activity through the state

The quakes have set record levels of seismic activity through the state

 

Austin Holland, a seismologist with the Oklahoma Geological Survey who tracks earthquake activity for the USGS, said the earthquake activity in the state is soaring.

‘We have had almost as many magnitude 3 and greater already in 2014 than we did for all of 2013,’ Holland said.

 

Last year’s number of ‘felt’ earthquakes – those strong enough to rattle items on a shelf – hit a record 222 in the state. This year, less than four months into the year, the state has recorded 253 such tremors, according to state seismic data.

 

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Yellowstone: M 4.7 Earthquake , 37km ENE of West Yellowstone, Montana – 13 EQ ranging in Magnitude from 2.5 to 4.7 in the last 5 days 3/31/2014

 photo MontanaYellowstone-48MagEQ3302014_zps98c00d38.png

13 earthquakes in map area

  1. M 3.1 – 35km NNE of Old Faithful Geyser, Wyoming

     2014-03-31 23:32:45 UTC-05:00 3.6 km

  2. M 2.7 – 33km ENE of West Yellowstone, Montana

     2014-03-30 12:37:31 UTC-05:00 5.1 km

  3. M 3.3 – 32km ENE of West Yellowstone, Montana

     2014-03-30 10:12:24 UTC-05:00 6.0 km

  4. M 3.1 – 32km ENE of West Yellowstone, Montana

     2014-03-30 10:07:49 UTC-05:00 6.6 km

  5. M 2.9 – 33km ENE of West Yellowstone, Montana

     2014-03-30 08:56:41 UTC-05:00 3.9 km

  6. M 3.6 – 34km ENE of West Yellowstone, Montana

     2014-03-30 08:30:52 UTC-05:00 4.4 km

  7. M 4.7 – 37km ENE of West Yellowstone, Montana

     2014-03-30 07:34:39 UTC-05:00 5.6 km

  8. M 2.5 – 35km ENE of West Yellowstone, Montana

     2014-03-30 07:18:58 UTC-05:00 3.6 km

  9. M 3.4 – 35km ENE of West Yellowstone, Montana

     2014-03-30 05:36:25 UTC-05:00 3.9 km

  10. M 2.8 – 36km ENE of West Yellowstone, Montana

     2014-03-30 01:23:48 UTC-05:00 1.5 km

  11. M 2.5 – 30km ENE of West Yellowstone, Montana

     2014-03-26 20:24:06 UTC-05:00 6.2 km

  12. M 3.5 – 30km ENE of West Yellowstone, Montana

     2014-03-26 18:59:00 UTC-05:00 4.5 km

  13. M 3.0 – 30km ENE of West Yellowstone, Montana

     2014-03-26 14:14:36 UTC-05:00 6.4 km

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 Huffington Post Green

Yellowstone National Park Hit By Magnitude 4.8 Earthquake

Posted: 03/31/2014 8:51 am EDT Updated: 03/31/2014 8:59 am EDT
YELLOWSTONE


By Laura Zuckerman

March 30 (Reuters) – Yellowstone National Park, which sits atop one of the world’s largest super-volcanoes, was struck on Sunday by a magnitude 4.8 earthquake, the biggest recorded there since February 1980, but no damage or injuries were immediately reported.

The tremor, a relatively light event by seismic standards, struck the northwest corner of the park and capped a flurry of smaller quakes at Yellowstone since Thursday, geologists at the University of Utah Seismograph Stations said in a statement.

The latest earthquake struck at 6:34 a.m. near the Norris Geyser Basin and was felt about 23 miles (37 km) away in two small Montana towns adjacent to year-around entrances to the park – Gardiner and West Yellowstone.

The national park spans 3,472 square miles (8,992 square km) of Wyoming, Montana and Idaho, and draws about 3 million visitors each year to its iconic geysers and wildlife attractions, including bison.

A U.S. Geological Survey team planned to tour the Norris Geyser Basin on Sunday to determine if the quake altered any of Yellowstone’s geothermal features, such as geysers, mud pots and hot springs.

 

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Instrumental Intensity

ShakeMap Intensity Image

 

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Recent Earthquakes in the Intermountain West

Yellowstone National Park Special Map

Special Map

get updated list here

 

Update time = Sun Mar 30 18:00:04 MDT 2014
Here are the earthquakes appearing on this map, most recent at top …

 MAG    DATE    LOCAL-TIME  LAT     LON    DEPTH    LOCATION
        y/m/d     h:m:s     deg     deg     km
 3.3  2014/03/30 09:12:24 44.777N 110.723W  6.0   29 km (18 mi) S   of  Gardiner, MT
 3.1  2014/03/30 09:07:49 44.770N 110.720W  6.6   30 km (18 mi) S   of  Gardiner, MT
 2.5  2014/03/30 07:56:40 44.770N 110.714W  7.7   30 km (18 mi) S   of  Gardiner, MT
 3.1  2014/03/30 07:30:52 44.772N 110.698W  4.5   29 km (18 mi) S   of  Gardiner, MT
 4.8  2014/03/30 06:34:39 44.778N 110.683W  6.8   29 km (18 mi) S   of  Gardiner, MT
 3.0  2014/03/30 04:36:25 44.786N 110.690W  1.6   28 km (17 mi) S   of  Gardiner, MT
 2.8  2014/03/30 00:23:48 44.785N 110.681W  1.5   28 km (17 mi) S   of  Gardiner, MT
 0.5  2014/03/28 09:41:43 44.825N 110.781W  3.1   24 km (15 mi) SSW of  Gardiner, MT
 2.0  2014/03/28 05:37:16 44.839N 110.513W  7.1   27 km (17 mi) SE  of  Gardiner, MT
 1.9  2014/03/26 18:58:40 44.808N 110.773W  4.3   26 km (16 mi) S   of  Gardiner, MT
 2.2  2014/03/26 18:20:59 44.800N 110.772W  4.1   27 km (17 mi) S   of  Gardiner, MT
 1.5  2014/03/26 18:11:57 44.821N 110.774W  2.0   24 km (15 mi) S   of  Gardiner, MT
 2.0  2014/03/26 18:00:10 44.799N 110.774W  3.9   27 km (17 mi) S   of  Gardiner, MT
 3.5  2014/03/26 17:59:00 44.801N 110.778W  4.5   27 km (17 mi) S   of  Gardiner, MT
 3.0  2014/03/26 13:14:36 44.804N 110.772W  6.4   26 km (16 mi) S   of  Gardiner, MT
 1.4  2014/03/24 12:06:51 44.246N 110.444W  3.6   70 km (43 mi) SE  of  West Yellowstone, MT
 1.7  2014/03/24 05:21:37 44.778N 110.774W  7.5   29 km (18 mi) S   of  Gardiner, MT
 1.1  2014/03/23 22:55:22 44.574N 110.410W  2.7   56 km (35 mi) E   of  West Yellowstone, MT

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UPI

Ancient helium rising to the surface in Yellowstone National Park

Feb. 20, 2014 at 4:46 PM

Steam plumes rise above thermal features at Yellowstone National Park. The U.S. Geological Survey determined the famed national park was releasing hundreds — if not thousands — of times more helium than anticipated. Credit: Ken McGee/U.S. Geological Survey

MENLO PARK, Calif., Feb. 20 (UPI) — Helium, trapped underground for 2 billion years, is bubbling to the surface from steam vents and hot springs of Yellowstone National Park, U.S. researchers say.Researchers with the U.S. Geological Survey say the park, located mostly in Wyoming, was releasing hundreds, even possible thousands, of times more of the ancient helium than previously thought, the Los Angeles Times reported Thursday.

About 60 tons are being release each year, enough helium to fill one Goodyear blimp every week, researchers said in a report published in the journal Nature.

Volcanic activity beginning about 2 million years ago initiated the release, they said.

That counts as a “sudden” release compared with how long the helium has been trapped within the Earth’s surface, study coauthor Bill Evans, a research chemist at the USGS office in Menlo Park, Calif., said.

 

 

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Earth Watch Report   –  Volcanic Actuivity

Copahue volcano, quiet at the surface, today (SERNAGEOMIN webcam)

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Volcano Activity MultiCountries Argentina and Chile (Andes), [Copahue Volcano] Damage level Details

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RSOE EDIS

Volcano Activity in MultiCountries on Saturday, 22 March, 2014 at 05:22 (05:22 AM) UTC.

Description
SERNAGEOMIN raised the alert level of the volcano to orange yesterday after an increase in seismic activity. A pulse of volcanic tremor was detected that could indicate magma moving into the volcano’s plumbing system. On the surface, no unusual activity has been seen at the volcano so far, except that an increase in SO2 emissions (approx 2,300 tons / day) was measured. This supports the idea that magma has risen under the edifice. Whether this activity is followed by new eruptive activity remains to be seen. In most cases, intrusions of magma under volcanoes do never reach the surface, i.e. produce eruptions. ONEMI (Civil Defense) published a bulletin stating that civil alert remains at yellow for the highest risk areas, in particular the most proximal areas around the volcano itself, but also include the city of Alto Biobío located 40 km west of the volcano, because it is at the mouth of a valley that drains Copahue on the north side and therefore, a potential pathway for mud flows that could occur during an eruption.

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Volcano Discovery

Copahue volcano

stratovolcano 2997 m / 9,833 ft
Chile/Argentina, -37.85°S / -71.17°W

Copahue webcams / live data
Copahue volcano videos
Copahue volcano eruptions:
2013, 2012, 2001(?), 2000, 1992, 1961, 1937, 1867(?), 1759(?), 1750
Typical eruption style:
explosive
Last earthquakes nearby

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Wednesday, Mar 12, 2014
The volcano continues to show signs of unrest. A swarm of volcanic-tectonic earthquakes occurred the day before yesterday. SERNAGEOMIN keeps the alert level of the volcano at Yellow. [more]

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Earth Watch Report  –  Earthquakes

Instrumental Intensity

ShakeMap Intensity Image

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M 4.1 – 12km WNW of Edgefield, South Carolina

 2014-02-15 03:23:38 UTC

Earthquake location 33.812°N, 82.063°W

Event Time

  1. 2014-02-15 03:23:38 UTC
  2. 2014-02-14 22:23:38 UTC-05:00 at epicenter
  3. 2014-02-14 21:23:38 UTC-06:00 system time

Location

33.812°N 82.063°W depth=4.8km (3.0mi)

Nearby Cities

  1. 12km (7mi) WNW of Edgefield, South Carolina
  2. 31km (19mi) NNE of Evans, Georgia
  3. 32km (20mi) N of Martinez, Georgia
  4. 35km (22mi) NNW of North Augusta, South Carolina
  5. 97km (60mi) WSW of Columbia, South Carolina

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Tectonic Summary

Earthquakes in the Inland Carolinas Region

Since at least 1776, people living inland in North and South Carolina, and in adjacent parts of Georgia and Tennessee, have felt small earthquakes and suffered damage from infrequent larger ones. The largest earthquake in the area (magnitude 5.1) occurred in 1916. Moderately damaging earthquakes strike the inland Carolinas every few decades, and smaller earthquakes are felt about once each year or two.

Earthquakes in the central and eastern U.S., although less frequent than in the western U.S., are typically felt over a much broader region. East of the Rockies, an earthquake can be felt over an area as much as ten times larger than a similar magnitude earthquake on the west coast. A magnitude 4.0 eastern U.S. earthquake typically can be felt at many places as far as 100 km (60 mi) from where it occurred, and it infrequently causes damage near its source. A magnitude 5.5 eastern U.S. earthquake usually can be felt as far as 500 km (300 mi) from where it occurred, and sometimes causes damage as far away as 40 km (25 mi).

Faults

Earthquakes everywhere occur on faults within bedrock, usually miles deep. Most bedrock beneath the inland Carolinas was assembled as continents collided to form a supercontinent about 500-300 million years ago, raising the Appalachian Mountains. Most of the rest of the bedrock formed when the supercontinent rifted apart about 200 million years ago to form what are now the northeastern U.S., the Atlantic Ocean, and Europe.

At well-studied plate boundaries like the San Andreas fault system in California, often scientists can determine the name of the specific fault that is responsible for an earthquake. In contrast, east of the Rocky Mountains this is rarely the case. The inland Carolinas region is far from the nearest plate boundaries, which are in the center of the Atlantic Ocean and in the Caribbean Sea. The region is laced with known faults but numerous smaller or deeply buried faults remain undetected. Even the known faults are poorly located at earthquake depths. Accordingly, few, if any, earthquakes in the inland Carolinas can be linked to named faults. It is difficult to determine if a known fault is still active and could slip and cause an earthquake. As in most other areas east of the Rockies, the best guide to earthquake hazards in the seismic zone is the earthquakes themselves.

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4.3 Quake In South Carolina.

BPEarthWatch BPEarthWatch

Published on Feb 14, 2014

This Quake shook from Alabama to Virginia.

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Jan. 24, 2014 at 6:44 PM ET

U.S. Geological Survey, file
Undated photo provided by the U.S. Geological Survey shows a landslide trench and ridge east of Reelfoot Lake in Obion County, Tenn., made by the New Madrid earthquakes in the early 1800s.

LOS ANGELES — The New Madrid fault zone in the nation’s midsection is active and could spawn future large earthquakes, scientists reported.

It’s “not dead yet,” said U.S. Geological Survey seismologist Susan Hough, who was part of the study published online Thursday by the journal Science.

Researchers have long debated just how much of a hazard New Madrid (MAD’-rihd) poses. The zone stretches 150 miles, crossing parts of Arkansas, Illinois, Indiana, Kentucky, Mississippi, Missouri and Tennessee.

In 1811 and 1812, it unleashed a trio of powerful jolts — measuring magnitudes 7.5 to 7.7 — that rattled the central Mississippi River valley. Chimneys fell and boats capsized. Farmland sank and turned into swamps. The death toll is unknown, but experts don’t believe there were mass casualties because the region was sparsely populated then.

Unlike California’s San Andreas and other faults that occur along boundaries of shifting tectonic plates, New Madrid is less understood since it’s in the middle of the continent, far from plate boundaries.

Previous studies have suggested that it may be shutting down, based on GPS readings that showed little strain accumulation at the surface. Other research came to the same conclusion by blaming ongoing quake activity on aftershocks from the 1800s, which would essentially relieve strain on the fault.

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DAHBOO77

Published on Nov 20, 2013

Following the Scotia Sea Activity, we will see these quakes in new locations!

http://quakes.globalincidentmap.com/

http://www.wcpo.com/news/state/state-…

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Examiner.com

Earthquake Ohio: 3.5 magnitude earthquake strikes southeastern Ohio

November 20, 2013

 Ohio earthquake news came from the southeastern part of the state on Wednesday (Nov. 20). The Ohio earthquake was near Athens, where students at the university there immediately reacted on Twitter. Many OU students were trying to figure out what had happened and it spurred quite a few online discussions. According to a report from The Columbus Dispatch, the U.S. Geological Survey reported it measured in at a 3.5-magnitude.

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M 3.5 – 4km ESE of Nelsonville, Ohio

2013-11-20 17:59:40 UTC

Earthquake location 39.439°N, 82.190°W

Event Time

  1. 2013-11-20 17:59:40 UTC
  2. 2013-11-20 12:59:40 UTC-05:00 at epicenter
  3. 2013-11-20 11:59:40 UTC-06:00 system time

Location

39.439°N 82.190°W depth=7.9km (4.9mi)

Nearby Cities

  1. 4km (2mi) ESE of Nelsonville, Ohio
  2. 14km (9mi) NNW of Athens, Ohio
  3. 46km (29mi) SE of Lancaster, Ohio
  4. 56km (35mi) WNW of Vienna, West Virginia
  5. 90km (56mi) SE of Columbus, Ohio

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Tectonic Summary

Earthquakes in the Stable Continental Region

Most of North America east of the Rocky Mountains has infrequent earthquakes. Here and there earthquakes are more numerous, for example in the New Madrid seismic zone centered on southeastern Missouri, in the Charlevoix-Kamouraska seismic zone of eastern Quebec, in New England, in the New York – Philadelphia – Wilmington urban corridor, and elsewhere. However, most of the enormous region from the Rockies to the Atlantic can go years without an earthquake large enough to be felt, and several U.S. states have never reported a damaging earthquake. The earthquakes that do occur can strike anywhere at irregular intervals.

Earthquakes east of the Rocky Mountains, although less frequent than in the West, are typically felt over a much broader region. East of the Rockies, an earthquake can be felt over an area as much as ten times larger than a similar magnitude earthquake on the west coast. A magnitude 4.0 eastern U.S. earthquake typically can be felt at many places as far as 100 km (60 mi) from where it occurred, and it infrequently causes damage near its source. A magnitude 5.5 eastern U.S. earthquake usually can be felt as far as 500 km (300 mi) from where it occurred, and sometimes causes damage as far away as 40 km (25 mi).

Faults

Earthquakes everywhere occur on faults within bedrock, usually miles deep. Most of the region’s bedrock was formed as several generations of mountains rose and were eroded down again over the last billion or so years.

At well-studied plate boundaries like the San Andreas fault system in California, often scientists can determine the specific fault that is responsible for an earthquake. In contrast, east of the Rocky Mountains this is rarely the case. All parts of this vast region are far from the nearest plate boundaries, which, for the U.S., are to the east in the center of the Atlantic Ocean, to the south in the Caribbean Sea, and to the west in California and offshore from Washington and Oregon. The region is laced with known faults but numerous smaller or deeply buried faults remain undetected. Even most of the known faults are poorly located at earthquake depths. Accordingly, few earthquakes east of the Rockies can be linked to named faults. It is difficult to determine if a known fault is still active and could slip and cause an earthquake. In most areas east of the Rockies, the best guide to earthquake hazards is the earthquakes themselves.

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Instrumental Intensity

ShakeMap Intensity Image

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Ohio- 3.5mag EQ  November 20th  2013 photo Ohio-35magEQNovember20th2013_zps1a40b323.jpg
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Active Volcano Discovered Under Ice Sheet in West Antarctica

Nov 18, 2013 by Sci-News.com

 

 

 

This map shows the location (red circle) of the newly discovered volcano in Marie Byrd Land, Antarctica.

This map shows the location (red circle) of the newly discovered volcano in Marie Byrd Land, Antarctica.

 

In 2010, the seismologists had set up two crossing lines of seismographs across Marie Byrd Land in West Antarctica. It was the first time scientists had deployed many instruments in the interior of the continent that could operate year-round even in the coldest parts of Antarctica.

 

The goal was essentially to weigh the ice sheet to help reconstruct Antarctica’s climate history. But to do this accurately the scientists had to know how the Earth’s mantle would respond to an ice burden, and that depended on whether it was hot and fluid or cool and viscous.

 

In the meantime, automated-event-detection software was put to work to comb the data for anything unusual.

 

In January 2010 and March 2011, the seismic network recorded two unusual bursts of seismic activity beneath Antarctica’s ice sheet.

 

“I started seeing events that kept occurring at the same location, which was odd. Then I realized they were close to some mountains, but not right on top of them,” explained PhD student Amanda Lough from Washington University in St. Louis, who is the lead author of the paper appearing in the journal Nature Geoscience.

 

“My first thought was, ‘OK, maybe it’s just coincidence.’ But then I looked more closely and realized that the mountains were actually volcanoes and there was an age progression to the range. The volcanoes closest to the seismic events were the youngest ones.”

 

The seismic events were weak and very low frequency, which strongly suggested they weren’t tectonic in origin.

 

While low-magnitude seismic events of tectonic origin typically have frequencies of 10 to 20 cycles per second, this shaking was dominated by frequencies of 2 to 4 cycles per second.

 

Ms Lough with colleagues used a global computer model of seismic velocities to relocate the hypocenters of the events to account for the known seismic velocities along different paths through the Earth. This procedure collapsed the swarm clusters to a third their original size. It also showed that almost all of the events had occurred at depths of 25 to 40 km.

 

Read More Here

 

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Antarctica, a land of ice and FIRE: Active volcano is discovered under continent  – and it could speed up melting

 

  • The volcano is buried 1km beneath the ice sheets of West Antarctica
  • Swarms of tremors were detected in January 2010 and February 2011
  • It was found near the extinct volcanoes of the Executive Committee Range
  • Ash found trapped in the ice came from an eruption 8,000 years ago
  • The volcano could cause the ice sheet to melt faster than first thought

By Victoria Woollaston

 

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Forget global warming, the ice sheets of Antarctica face a different and a potentially more imminent threat in the form an active volcano buried deep beneath. 

Researchers from Washington University discovered the volcano – which is yet to be named – by accident in the Marie Byrd Land region of West Antarctica. 

Swarms of tremors were detected in January 2010 and February 2011 and ash found trapped in the ice suggest it has been active for around 8,000 years.

The new volcano was found buried around a kilometre beneath an ice sheet in West Antarctica, close to the Executive Committee Range of mountains, pictured.

The new volcano was found buried beneath an ice sheet in West Antarctica, close to the Executive Committee Range of mountains, pictured. While trying to establish the weight of the ice sheet in the region, seismometers measured two swarms of tremors suggesting the volcano is active

MOUNTAINS DEEP BENEATH THE ICE

The as yet unnamed volcano buried beneath the ice sheet in Marie Byrd Land, West Antarctica is believed to be located close to the Executive Committee Range of extinct volcanoes.

The Range is made up consisting of five major volcanoes which were found by the United States Antarctic Service expedition in 1940.

It is named after the Antarctic Service Executive Committee.

The mountains are called Mount Sidley, Mount Waesche, Mount Hampton, Mount Cumming and Mount Hartington and are named after members of the committee.

Further mountains, thought to be extinct volcanoes, were discovered in East Antarctica in 1958.

This range is called the Gamburtsev Mountain Range and is covered by around 6 kilometres of snow and ice.

It is thought to be similar in size to the Alps.

Like with the new volcano, and the Executive Committee range, it is unclear exactly what caused these mountains to form.

 

Scientists now believe that a large eruption could cause the ice sheet to melt faster than first thought and cause sea levels to rise.

In January 2010, a team of scientists from the St. Louis-based university set up two crossing lines of seismographs across Marie Byrd Land in West Antarctica.

Doug Wiens, professor of earth and planetary science at Washington University, and his team wanted to weigh the ice sheet to help create a picture of Antarctica’s climate history.

Like a giant CT machine, the seismograph array used disturbances created by distant earthquakes to make images of the ice and rock deep within the region.

The technology found two bursts of seismic events between January 2010 and March 2011, which Wiens’ PhD student Amanda Lough believed were caused by a previously unseen volcano buried over half a mile (1 kilometre) beneath the ice sheet.  

‘I started seeing events that kept occurring at the same location, which was odd,’ Lough said.

‘Then I realised they were close to some mountains – but not right on top of them.

‘My first thought was, “Okay, maybe it’s just coincidence.” But then I looked more closely and realised that the mountains were actually volcanoes and there was an age progression to the range.

‘The volcanoes closest to the seismic events were the youngest ones.’

The tremors were weak and very low frequency, which Lough said suggested they weren’t caused by movements in tectonic plates, associated with earthquakes. 

The tremors beneath Marie Byrd Land, pictured, were weak and very low frequency, which Lough said suggested they weren't caused by movements in tectonic plates

The tremors beneath Marie Byrd Land, pictured, were low frequency suggesting they weren’t caused tectonic plates moving. Low-magnitude tectonic tremors typically have frequencies of 10 to 20 cycles per second. The shaking discovered by Lough was 2 to 4 cycles per second making it more like volcanic activity

For example, low-magnitude seismic tremors caused by tectonic movement typically have frequencies of 10 to 20 cycles per second, continued Lough.

The shaking she discovered was in frequencies of 2 to 4 cycles per second.

Lough then used a global computer model of seismic speeds to find exactly where the seismic events were taking place. 

Read More Here

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Earth Watch Report  –  Earthquakes

Scotia Sea  -  6.8 Mag EQ  November 15th  2013 a photo ScotiaSea-68MagEQNovember15th2013a_zps4c8b89e0.jpg

Scotia Sea  -  6.8 Mag EQ  November 15th  2013 b photo ScotiaSea-68MagEQNovember15th2013b_zps7fece93f.jpg

5 earthquakes in map area

  1. M 5.3 – Scotia Sea   2013-11-15 22:45:33 UTC-06:00 10.0 km

  2. M 4.8 – Scotia Sea  2013-11-15 22:16:04 UTC-06:00 10.2 km

  3. M 4.9 – Scotia Sea  2013-11-15 22:01:18 UTC-06:00 10.3 km

  4. M 6.8 – Scotia Sea  2013-11-15 21:34:31 UTC-06:00 10.0 km

  5. M 4.4 – Scotia Sea  2013-11-15 02:10:17 UTC-06:00 10.0 km

Scotia Sea  -  6 EQ mag 4.4 to 6.8  last 7 days  November 15th  2013 photo ScotiaSea-6EQmag44to68last7daysNovember15th2013_zps3664aa2d.jpg
Scotia Sea  –  6 EQ mag 4.4 to 6.8  last 3 days  November 15th  2013

6 earthquakes in map area

  1. 5.3 Scotia Sea 2013-11-15 22:45:33 UTC-06:00 10.0 km
  2. 4.8 Scotia Sea 2013-11-15 22:16:04 UTC-06:00 10.2 km
  3. 4.9 Scotia Sea 2013-11-15 22:01:18 UTC-06:00 10.3 km
  4. 6.8 Scotia Sea 2013-11-15 21:34:31 UTC-06:00 10.0 km
  5. 4.4 Scotia Sea 2013-11-15 02:10:17 UTC-06:00 10.0 km
  6. 6.1 Scotia Sea 2013-11-13 17:45:48 UTC-06:00 10.0 km

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M 6.8 – Scotia Sea

 2013-11-16 03:34:31 UTC

Earthquake location 60.213°S, 47.108°W

Event Time

  1. 2013-11-16 03:34:31 UTC
  2. 2013-11-16 00:34:31 UTC-03:00 at epicenter
  3. 2013-11-15 21:34:31 UTC-06:00 system time

Location

60.213°S 47.108°W depth=10.0km (6.2mi)

Nearby Cities

  1. 917km (570mi) SW of Grytviken, South Georgia and the South Sandwich Islands
  2. 1397km (868mi) SE of Ushuaia, Argentina
  3. 1644km (1022mi) SE of Punta Arenas, Chile
  4. 1668km (1036mi) SE of Rio Gallegos, Argentina
  5. 1158km (720mi) SSE of Stanley, Falkland Islands

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Instrumental Intensity

ShakeMap Intensity Image

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Scotia Sea  -  6.8 Mag EQ  November 15th  2013 photo ScotiaSea-68MagEQNovember15th2013_zpsf139f398.jpg
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First Posted: Apr 18, 2013 04:07 PM EDT

 

Yellowstone

When volcanoes erupt, silica-rich magma can burst through the Earth’s crust, burning the surrounding area in a massive explosion. Now, it turns out that this magma can lurk in Earth’s upper crust for hundreds of thousands of years without triggering an eruption. (Photo : Flickr/Don Graham)

 

Yellowstone has the world’s largest collection of geysers, and it has the underground plumbing to prove it. Scientists have announced that the volcanic activity beneath the National Park’s surface may be far bigger and better connected than once thought.

 

The National Park is home to hot springs, mudpots, fumaroles and geysers, so it’s not surprising that it has quite a bit of volcanic activity under the ground. Known as a hotspot, a massive volume of molten magma is located beneath Yellowstone. This plume of superheated rock rises from Earth’s mantle, punching through the continent’s crust as North America has slowly drifted over it. The phenomenon has left a trail of calderas created by massive volcanic eruptions in its wake; the most recent occurred about 640,000 years ago.

 

Yellowstone is infamous for its potential for a “super eruption.” When the Huckleberry Ridge eruption in Yellowstone occurred about 2 million years ago, it darkened the skies with ash from southern California to the Mississippi River. It was one of the largest eruptions to have occurred on our planet. Understanding the volcanic activity of this location is therefore crucial for predicting future eruptions.

 

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nature.com

 

Large magma reservoir gets bigger

 

But earthquakes, not eruptions, are Yellowstone’s most serious geological risk.

 

 

28 October 2013

 

 

 

The reservoir of molten rock underneath Yellowstone National Park in the United States is at least two and a half times larger than previously thought. Despite this, the scientists who came up with this latest estimate say that the highest risk in the iconic park is not a volcanic eruption but a huge earthquake.

 

Yellowstone is famous for having a ‘hot spot’ of molten rock that rises from deep within the planet, fuelling the park’s geysers and hot springs1. Most of the magma resides in a partially molten blob a few kilometres beneath Earth’s surface.

 

New pictures of this plumbing system show that the reservoir is about 80 kilometres long and 20 kilometres wide, says Robert Smith, a geophysicist at the University of Utah in Salt Lake City. “I don’t know of any other magma body that’s been imaged that’s that big,” he says.

 

Smith reported the finding on 27 October at the annual meeting of the Geological Society of America in Denver, Colorado.

 

Yellowstone lies in the western United States, where the mountain states of Wyoming, Montana and Idaho converge. The heart of the park is a caldera — a giant collapsed pit left behind by the last of three huge volcanic eruptions in the past 2.1 million years.

 

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