Yellowstone Recent Status Report, Updates, and Information Releases
Friday, January 9, 2009 19:44 MST (Saturday, January 10, 2009 02:44 UTC)
YELLOWSTONE VOLCANO (CAVW#1205-01-)
44.43°N 110.67°W, Summit Elevation 9203 ft (2805 m)
Volcano Alert Level: NORMAL
Aviation Color Code: GREEN
Small Earthquake Swarm on 9 January 2009 near northeast corner of Yellowstone Caldera
A currently modest swarm of earthquakes began in the northeast corner of the Yellowstone Caldera, about 10 miles (16 km) NNE of the north end of the Yellowstone Lake swarm that was active in late December and early January. As of 1930 MST, 10 earthquakes had been located by the University of Utah Seismograph Stations, the largest with M= 3.3 and two other events with M >2.0. Located depths are between 2 and 4 km.
Yellowstone Volcano Observatory staff and collaborators are analyzing the data from this and from the earlier Yellowstone Lake swarm and are checking for any changes to the thermal areas located near the epicenters. We will provide further information as it becomes available.
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The Yellowstone Volcano Observatory (YVO) is a partnership of the U.S. Geological Survey (USGS), Yellowstone National Park, and University of Utah to strengthen the long-term monitoring of volcanic and earthquake unrest in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.
Tuesday, January 6, 2009 00:39 MST (Tuesday, January 6, 2009 07:39 UTC)
YELLOWSTONE VOLCANO (CAVW#1205-01-)
44.43°N 110.67°W, Summit Elevation 9203 ft (2805 m)
Volcano Alert Level: NORMAL
Aviation Color Code: GREEN
Yellowstone Lake Earthquake Swarm Summary as of 6 January 2009
Through 5 January 2009, seismic activity has markedly decreased. It is possible that the swarm has ended, though a return of activity may occur as Yellowstone swarms of the size usually last for tens of days to many weeks.
About 500 earthquakes occurred between Dec. 26 through Jan. 1. Three hundred of the earthquakes (including all >M2.0) have been reviewed by seismologists. There have been 86 earthquakes with M > 2.0 and 16 earthquakes > M3.0. About 200 smaller earthquakes have yet to be reviewed. Depths are difficult to determine accurately. The best located earthquakes have depths on the order of 3 to 10 km (1.8 to 6.0 miles). From Dec. 26 through Jan 2, the earthquake hypocenters appear to have migrated northwards, starting southeast of near Stevenson Island, with many of the latest events occurring near Fishing Bridge.
The recent swarm is well above typical activity at Yellowstone. Nevertheless it is not unprecedented during the last 40 years of monitoring. Swarms are the typical mode of occurrence of earthquakes within the Yellowstone caldera, with magnitudes ranging to > 4.0. The 1985 swarm on the northwest rim of the caldera lasted for three months, with earthquakes up to M4.9 and over 3000 total events recorded.
Magnitudes of earthquakes in this swarm range from zero to 3.9. Seismologists categorize those of magnitude less than 3.5 as generally not felt by persons. For perspective, earthquakes of magnitude 3.4 to 4.5 are often felt, as several of the events in this swarm have. A magnitude 5 or greater is generally required to produce damage to buildings or other structures.
Improved volcano and seismic monitoring at Yellowstone gives us a greater ability to locate earthquakes, understand their source process and identify anomalous sources of seismic activity. New equipment including precise measurements of ground motion by GPS receivers and borehole strainmeters provided by the National Science Foundation's EarthScope and Continental Dynamics Program have been used extensively during the last week of intense earthquake activity. Ground motions accompanying the swarm, from the GPS instruments will take two or more weeks to fully process. It is worth noting that in 2004 the Yellowstone caldera began a period of accelerated uplift measured by GPS instruments that was as large as 7 cm/yr (2.7 inches/yr), three times as fast as recorded in the recorded history but has now reduced to about a maximum rate of 4 cm/yr. Scientists have modeled this deformation as due to magmatic recharge of the Yellowstone magma chamber at a depth of ~10 km (6 miles). The area of the swarm is on the eastern side of the uplift area.
Earthquakes at Yellowstone are caused by a combination of geological factors including: 1) regional stress associated with normal faults (those where the valleys go down relative to the mountains) such as the nearby Teton and Hebgen Lake faults, 2) magmatic movements at depth (>7 kms or 4 miles), and 3) hydrothermal fluid activity caused as the groundwater system is heated to boiling by magmatic heat.
At this time, no one has noted any anomalous changes in surface discharges (hot springs, gas output, etc.).
YVO staff from the USGS, University of Utah and Yellowstone National Park continue to carefully review all data streams that are recorded in real-time. At this time, there is no reason to believe that magma has risen to a shallow level within the crust or that a volcanic eruption is likely. The USGS Volcano alert level for Yellowstone Volcano remains at Normal/Green.
Yellowstone National Park is evaluating infrastructure near the north end of Yellowstone Lake to assess if any damage has occurred to facilities.
Winter visitor activities and staff operations have not been impacted and continue as normal.
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The Yellowstone Volcano Observatory (YVO) is a partnership of the U.S. Geological Survey (USGS), Yellowstone National Park, and University of Utah to strengthen the long-term monitoring of volcanic and earthquake unrest in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.
Friday, January 2, 2009 19:30 MST (Saturday, January 3, 2009 02:30 UTC)
YELLOWSTONE VOLCANO (CAVW#1205-01-)
44.43°N 110.67°W, Summit Elevation 9203 ft (2805 m)
Volcano Alert Level: NORMAL
Aviation Color Code: GREEN
Yellowstone Lake Earthquake Swarm Update: 2 January 2008
The University of Utah Seismograph Stations reports that as of 1800 MST on 2 January 2009, seismicity of the ongoing Yellowstone earthquake swarm continues. Over 500 earthquakes, as large as M 3.9, have been recorded by an automated earthquake system since the inception of this unusual earthquake sequence that began Dec. 27, 2008. More than 300 of these events have been reviewed and evaluated by seismic analysts. Depths of the earthquakes range from ~ 1km to around 10 km. We note that the earthquakes extend northward from central Yellowstone Lake for ~10 km toward the Fishing Bridge area, with a migration of recent earthquakes toward the north. Some of the dozen M3+ earthquakes were felt in the Lake, Grant Village and Old Faithful areas. Personnel of the Yellowstone Volcano Observatory continue to evaluate this earthquake sequence and will provide information to the NPS, USGS and the public as it evolves.
This earthquake sequence is the most intense in this area for some years. No damage has been reported within Yellowstone National Park, nor would any be expected from earthquakes of this size. The swarm is in a region of historical earthquake activity and is close to areas of Yellowstone famous hydrothermal activity. Similar earthquake swarms have occurred in the past in Yellowstone without triggering steam explosions or volcanic activity. Nevertheless, there is some potential for hydrothermal explosions and earthquakes may continue or increase in magnitude. There is a much lower potential for related volcanic activity.
The University of Utah operates a seismic network in Yellowstone National Park in conjunction with the National Park Service and the U.S. Geological Survey. These three institutions are partners in the Yellowstone Volcano Observatory. Seismic data from Yellowstone are transmitted to the University in real-time by radio and satellite links from a network of 28 seismographs in the Yellowstone area and are available on the web.
Seismologists continue to monitor and analyze data from this swarm of earthquakes and provide updates to the NPS and USGS and to the public via the following web pages.
Information on U.S. earthquake activity including Yellowstone can be viewed at the U.S. Geological Survey web site: http://earthquake.usgs.gov/eqcenter/recenteqsus/.
Information on earthquakes can also be viewed at the University of Utah
Seismograph Stations web site: http://www.seis.utah.edu/.
Seismographic recordings from Yellowstone seismograph stations can be
viewed online at: http://www.quake.utah.edu/helicorder/heli/yellowstone/index.html.
An article on earthquake swarms at Yellowstone is available at the following: http://volcanoes.usgs.gov/yvo/publications/2004/apr04swarm.php
Persons who felt any of the earthquakes are encouraged to fill out a survey form on the USGS 'Did You Feel It?' web site: http://earthquake.usgs.gov/eqcenter/dyfi/.
Geologic information, maps, and monitoring information for Yellowstone can be found on the Yellowstone Volcano Observatory web site at:
http://volcanoes.usgs.gov/yvo/.
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The Yellowstone Volcano Observatory (YVO) is a partnership of the U.S. Geological Survey (USGS), Yellowstone National Park, and University of Utah to strengthen the long-term monitoring of volcanic and earthquake unrest in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.
Thursday, January 1, 2009 07:57 MST (Thursday, January 1, 2009 14:57 UTC)
YELLOWSTONE VOLCANO (CAVW#1205-01-)
44.43°N 110.67°W, Summit Elevation 9203 ft (2805 m)
Volcano Alert Level: NORMAL
Aviation Color Code: GREEN
December 2008 Yellowstone Earthquake And Ground Deformation Summary
Earthquake Summary:
Yellowstone seismicity increased significantly in December 2008 due to an energetic earthquake swarm that commenced on December 26. This swarm, a sequence of earthquakes clustered in space and time, is occurring beneath the northern part of Yellowstone Lake in Yellowstone National Park. As of this writing, the largest of these earthquakes was a magnitude 3.9 at 10:15 pm MST on Dec. 27. Through 5:00 pm MST on Dec. 31, the sequence had included 12 events of magnitude 3.0 to 3.9 and approximately 20 of magnitude 2.5 to 2.9, with a total of at least 400 events large enough to be located (magnitude ~1 or larger). National Park Service (NPS) employees and visitors have reported feeling the largest of these earthquakes in the area around Yellowstone Lake and at Old Faithful and Grant Village.
The hypocenters of the swarm events cluster along a north-south-trending zone that is about 7 km long. The vast majority of the focal depths are shallower than 5 km. It is not possible to identify a causative fault of other feature without further analysis.
Analysts are currently processing the backlog of seismic data from these events. The current analyst-processed catalog is believed to include all events of magnitude 2.5 and greater through Dec 31 at 5 pm MST, but hundreds of earthquakes remain to be processed. The total of more than 400 locatable events is based on automatically-determined locations and magnitudes for the swarm events.
The December 2008 earthquake sequence is the most intense in this area for some years. No damage has been reported within Yellowstone National Park, nor would any be expected from earthquakes of this size. The swarm is in a region of historical earthquake activity and is close to areas of Yellowstone famous hydrothermal activity. Similar earthquake swarms have occurred in the past in Yellowstone without triggering steam explosions or volcanic activity. Nevertheless, there is some potential for hydrothermal explosions and earthquakes may continue or increase in magnitude. There is a much lower potential for related volcanic activity.
The National Park Service in Yellowstone has been kept fully informed of the ongoing seismic activity via electronic means and by phone contacts with the University of Utah and the U.S. Geological Survey USGS). The Wyoming Office of Homeland Security is reviewing Earthquake Response Plans and monitoring seismic activity.
Earthquakes are a common occurrence in the Yellowstone National Park area, an active volcanic-tectonic area averaging 1,000 to 2,000 earthquakes a year. Yellowstone's 10,000 geysers and hot springs are the result of this geologic activity. A summary of Yellowstone's volcanic history is available on the Yellowstone Volcano Observatory web site (listed below).
The University of Utah operates a seismic network in Yellowstone National Park in conjunction with the National Park Service and the U.S. Geological Survey. These three institutions are partners in the Yellowstone Volcano Observatory. Seismic data from Yellowstone are transmitted to the University in real-time by radio and satellite links from a network of 28 seismographs in the Yellowstone area and are available on the web.
Seismologists continue to monitor and analyze data from this swarm of earthquakes and provide updates to the NPS and USGS and to the public via the following web pages.
Information on U.S. earthquake activity including Yellowstone can be viewed at the U.S. Geological Survey web site: http://earthquake.usgs.gov/eqcenter/recenteqsus/.
Information on earthquakes can also be viewed at the University of Utah
Seismograph Stations web site: http://www.seis.utah.edu/.
Seismographic recordings from Yellowstone seismograph stations can be
viewed online at: http://www.quake.utah.edu/helicorder/heli/yellowstone/index.html.
An article on earthquake swarms at Yellowstone is available at the following: http://volcanoes.usgs.gov/yvo/publications/2004/apr04swarm.php
Persons who felt any of the earthquakes are encouraged to fill out a survey form on the USGS 'Did You Feel It?' web site: http://earthquake.usgs.gov/eqcenter/dyfi/.
Geologic information, maps, and monitoring information for Yellowstone can be found on the Yellowstone Volcano Observatory web site at:
http://volcanoes.usgs.gov/yvo/.
Ground Deformation Summary:
Through December 2008, continuous GPS data show that much of the Yellowstone caldera continued moving upward, though at a lower rate than the past few years. The maximum measured ground uplift over the past 53 months is ~23 cm at the White Lake GPS station, north of Fishing Bridge. An example can be found at:
http://pboweb.unavco.org/shared/scripts/stations/?checkkey=WLWY&sec=timeseries_plots×eries=raw.
The general uplift of the Yellowstone caldera is scientifically important and will continue to be monitored and studied closely by YVO staff.
A discussion of the current uplift episode at Yellowstone and long-term ground deformation at Yellowstone and elsewhere can be found at: http://volcanoes.usgs.gov/yvo/publications/2007/upsanddowns.php.
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The Yellowstone Volcano Observatory (YVO) is a partnership of the U.S. Geological Survey (USGS), Yellowstone National Park, and University of Utah to strengthen the long-term monitoring of volcanic and earthquake unrest in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.
Monday, December 29, 2008 19:07 MST (Tuesday, December 30, 2008 02:07 UTC)
YELLOWSTONE VOLCANO (CAVW#1205-01-)
44.43°N 110.67°W, Summit Elevation 9203 ft (2805 m)
Volcano Alert Level: NORMAL
Aviation Color Code: GREEN
Earthquake swarm beneath Yellowstone Lake continues.
PRESS RELEASE FROM YVO PARTNER UNIVERSITY OF UTAH SEISMOGRAPH STATIONS
Released: December 29, 2008 05:00 PM MST
The University of Utah Seismograph Stations reports that a notable swarm of earthquakes has been underway since December 26 beneath Yellowstone Lake in Yellowstone National Park, three to six miles south-southeast of Fishing Bridge, Wyoming. This energetic sequence of events was most intense on December 27, when the largest number of events of magnitude 3 and larger occurred.
The largest of the earthquakes was a magnitude 3.9 (revised from magnitude 3.8) at 10:15 pm MST on Dec. 27. The sequence has included nine events of magnitude 3 to 3.9 and approximately 24 of magnitude 2 to 3 at the time of this release. A total of more than 250 events large enough to be located have occurred in this swarm. Reliable depths of the larger events are up to a few miles. Visitors and National Park Service (NPS) employees in the Yellowstone Lake area reported feeling the largest of these earthquakes.
Earthquakes are a common occurrence in the Yellowstone National Park area, an active volcanic-tectonic area averaging 1,000 to 2,000 earthquakes a year. Yellowstone's 10,000 geysers and hot springs are the result of this geologic activity. A summary of Yellowstone's volcanic history is available on the Yellowstone Volcano Observatory web site (listed below). This December 2008 earthquake sequence is the most intense in this area for some years and is centered on the east side of the Yellowstone caldera. Scientists cannot identify any causative fault or other feature without further analysis. Seismologists continue to monitor and analyze the data and will issue new information if the situation warrants it.
The University of Utah operates a seismic network in Yellowstone National Park in conjunction with the National Park Service and the U.S. Geological Survey (USGS). These three institutions are partners in the Yellowstone Volcano Observatory.
Data are transmitted to the University in real-time by radio and satellite links from a network of 28 seismographs in the Yellowstone area and are available on the web. Seismologists continue to analyze data from this swarm of earthquakes and provide updates to the NPS and USGS and to the public via the following web pages.
Information on U.S. earthquake activity including Yellowstone can be viewed at the U.S. Geological Survey web site: http://earthquake.usgs.gov/eqcenter/recenteqsus/
Information on earthquakes can also be viewed at the University of Utah Seismograph Stations web site:
http://www.seis.utah.edu/.
Seismographic recordings from Yellowstone seismograph stations can be viewed online at:
http://www.quake.utah.edu/helicorder/heli/yellowstone/index.html.
Persons who felt any of the earthquakes are encouraged to fill out a survey form on the USGS 'Did You Feel It?' web site: http://earthquake.usgs.gov/eqcenter/dyfi/.
Geologic information, maps, and monitoring information for Yellowstone can be found on the Yellowstone Volcano Observatory web site at: http://volcanoes.usgs.gov/yvo/.
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The Yellowstone Volcano Observatory (YVO) is a partnership of the U.S. Geological Survey (USGS), Yellowstone National Park, and University of Utah to strengthen the long-term monitoring of volcanic and earthquake unrest in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.
Saturday, December 27, 2008 20:29 MST (Sunday, December 28, 2008 03:29 UTC)
YELLOWSTONE VOLCANO (CAVW#1205-01-)
44.43°N 110.67°W, Summit Elevation 9203 ft (2805 m)
Volcano Alert Level: NORMAL
Aviation Color Code: GREEN
PRESS RELEASE FROM YVO PARTNER UNIVERSITY OF UTAH SEISMOGRAPH STATIONS
Released: December 27, 2008 04:40 PM MST
The University of Utah Seismograph Stations reports that a swarm of small earthquakes of magnitude 3.5 and smaller is occurring beneath Yellowstone Lake in Yellowstone National Park, five to nine miles south-southeast of Fishing Bridge, Wyoming. The swarm began yesterday afternoon, Dec. 26, and has continued and intensified today. The two largest earthquakes in this swarm have been shocks of magnitude 3.5 and 3.4 which occurred at 1:17 and 1:26 pm MST, respectively, today. Many smaller earthquakes have also occurred, including three events this morning of magnitude 2.5 to 2.8 and a magnitude 3.2 event at 3:30 pm MST. Some of the earthquakes in the swarm have been reported felt by people in the Yellowstone Lake area. Swarms of this nature are relatively common in this part of Yellowstone Park.
Summary for Largest Earthquake:
Date (UTC): December 27, 2008 Time (UTC): 20:17
Date (local): December 27, 2008 Time (local): 01:17 PM MST
Latitude: 44 28.85' N
Longitude: 110 21.74' W
Magnitude: average Ml: 3.50
average Mc: 3.6
Reported magnitude: 3.50
For the next ten days, an image of today's recordings from the nearby LKWY seismograph station can be viewed at:
http://www.seis.utah.edu/helicorder/heli/yellowstone/Uuss.LKWY_SHZ_US.2008122700.gif
After ten days, the image will be replaced by more recent data.
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The Yellowstone Volcano Observatory (YVO) is a partnership of the U.S. Geological Survey (USGS), Yellowstone National Park, and University of Utah to strengthen the long-term monitoring of volcanic and earthquake unrest in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.
Monday, December 1, 2008 12:06 MST (Monday, December 1, 2008 19:06 UTC)
YELLOWSTONE VOLCANO (CAVW#1205-01-)
44.43°N 110.67°W, Summit Elevation 9203 ft (2805 m)
Volcano Alert Level: NORMAL
Aviation Color Code: GREEN
NOVEMBER 2008 Yellowstone Seismicity Summary
During the month of November 2008, 166 earthquakes were located in the Yellowstone region. The largest event was a magnitude 2.7 on November 23 at 11:41 PM MST, located about 21 miles south southeast of West Thumb, YNP, and near the southern caldera boundary. This event was part of a swarm of 77 events, Nov. 23 -29, with magnitudes -0.3 - 2.7. Two smaller swarms were also recored in November. One located about 9 miles northeast of West Yellowstone, MT. The swarm included 17 events, Nov. 7 - 12, with magnitudes 0.0 - 1.4. The second was located about 17 miles east northeast of West Yellowstone, MT. The swarm included 21 events, Nov. 24 - 25, with magnitudes -0.1 - 1.6.
Earthquake activity in the Yellowstone region is at relatively normal background levels.
Ground Deformation Summary: Through November 2008, continuous GPS data show that much of the Yellowstone caldera continued moving upward, though at a lower rate than the past several years. The maximum measured ground uplift over the past 53 months is ~22 cm at the White Lake GPS station. An example can be found at: http://pboweb.unavco.org/shared/scripts/stations/checkkey=WLWY&sec=timeseries_plots×eries=raw
The general uplift of the Yellowstone caldera is scientifically interesting and will continue to be monitored closely by YVO staff.
An article on the current uplift episode at Yellowstone and discussion of long-term ground deformation at Yellowstone and elsewhere can be found at: http://volcanoes.usgs.gov/yvo/publications/2007/upsanddowns.php
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The Yellowstone Volcano Observatory (YVO) is a partnership of the U.S. Geological Survey (USGS), Yellowstone National Park, and University of Utah to strengthen the long-term monitoring of volcanic and earthquake unrest in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.
Saturday, November 1, 2008 16:50 MDT (Saturday, November 1, 2008 22:50 UTC)
YELLOWSTONE VOLCANO (CAVW#1205-01-)
44.43°N 110.67°W, Summit Elevation 9203 ft (2805 m)
Volcano Alert Level: NORMAL
Aviation Color Code: GREEN
OCTOBER 2008 Yellowstone Seismicity Summary
During the month of October 2008, 46 earthquakes were located in the Yellowstone region. The largest event was a magnitude 2.4 on October 5 at 3:12 PM MDT, located about 13 miles northeast of West Yellowstone, MT. No swarms were recorded during October.
Earthquake activity in the Yellowstone region is at relatively low background levels.
Ground Deformation Summary: Through October 2008, continuous GPS data show that much of the Yellowstone caldera continued moving upward, though at a lower rate than the past several years. The maximum measured ground uplift over the past 50 months is ~21 cm at the White Lake GPS station. An example can be found at: http://pboweb.unavco.org/shared/scripts/stations/?checkkey=WLWY&sec=timeseries_plots×eries=raw
The general uplift of the Yellowstone caldera is scientifically interesting and will continue to be monitored closely by YVO staff.
An article on the current uplift episode at Yellowstone and discussion of long-term ground deformation at Yellowstone and elsewhere can be found at: http://volcanoes.usgs.gov/yvo/2007/upsanddowns.html
-----
The Yellowstone Volcano Observatory (YVO) is a partnership of the U.S. Geological Survey (USGS), Yellowstone National Park, and University of Utah to strengthen the long-term monitoring of volcanic and earthquake unrest in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.
Wednesday, October 1, 2008 11:42 MDT (Wednesday, October 1, 2008 17:42 UTC)
YELLOWSTONE VOLCANO (CAVW#1205-01-)
44.43°N 110.67°W, Summit Elevation 9203 ft (2805 m)
Volcano Alert Level: NORMAL
Aviation Color Code: GREEN
SEPTEMBER 2008 Yellowstone Seismicity Summary
During the month of September 2008, 62 earthquakes were located in the Yellowstone region. The largest event was a magnitude 2.9 on September 25 at 12:07 PM MDT, located about 16 miles southeast of West Thumb, YNP, and near the southern caldera boundary. This event was part of a swarm of 19 events with magnitudes 0.9 - 2.9.
Earthquake activity in the Yellowstone region is at normal background levels.
Ground Deformation Summary: Through September 2008, continuous GPS data show that much of the Yellowstone caldera continued moving upward, though at a lower rate than the past several years. The maximum measured ground uplift over the past 50 months is ~21 cm at the White Lake GPS station. An example can be found at: http://pboweb.unavco.org/shared/scripts/stations/?checkkey=WLWY&sec=timeseries_plots×eries=raw
The general uplift of the Yellowstone caldera is scientifically interesting and will continue to be monitored closely by YVO staff.
An article on the current uplift episode at Yellowstone and discussion of long-term ground deformation at Yellowstone and elsewhere can be found at: http://volcanoes.usgs.gov/yvo/2007/upsanddowns.html
-----
The Yellowstone Volcano Observatory (YVO) is a partnership of the U.S. Geological Survey (USGS), Yellowstone National Park, and University of Utah to strengthen the long-term monitoring of volcanic and earthquake unrest in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.
Tuesday, September 2, 2008 13:31 MDT (Tuesday, September 2, 2008 19:31 UTC)
YELLOWSTONE VOLCANO (CAVW#1205-01-)
44.43°N 110.67°W, Summit Elevation 9203 ft (2805 m)
Volcano Alert Level: NORMAL
Aviation Color Code: GREEN
AUGUST 2008 Yellowstone Seismicity Summary
During the month of August 2008, 146 earthquakes were located in the Yellowstone region. The largest event was a magnitude 2.3 on August 31 at 7:31 AM MDT, located about 17 miles west northwest of West Yellowstone, MT. Three swarms occurred during the month of August. The first was a continuation of of a swarm that started July 28th on the Madison Plateau. The swarm continued until August 5th with an additional 52 events with magnitudes from -0.4 to 2.1, bringing the total for the swarm to 184 earthquakes. The second swarm, between Aug 3 and 7, included 28 events and was located 16 miles east northeast of West Yellowstone, MT with magnitudes 0.0 to 1.4. The third swarm on August 7 and 8 included 32 events, and was located 6 miles southeast of West Thumb. Magnitudes ranged from 0.0 to 2.1.
Earthquake activity in the Yellowstone region is at relatively low background levels.
Ground Deformation Summary: Through August 2008, continuous GPS data show that much of the Yellowstone caldera continued moving upward, though at a lower rate than the past several years. The maximum measured ground uplift over the past 48 months is ~20 cm at the White Lake GPS station. An example can be found at: http://pboweb.unavco.org/shared/scripts/stations/?checkkey=WLWY&sec=timeseries_plots×eries=raw
The general uplift of the Yellowstone caldera is scientifically interesting and will continue to be monitored closely by YVO staff.
An article on the current uplift episode at Yellowstone and discussion of long-term ground deformation at Yellowstone and elsewhere can be found at: http://volcanoes.usgs.gov/yvo/2007/upsanddowns.html
-----
The Yellowstone Volcano Observatory (YVO) is a partnership of the U.S. Geological Survey (USGS), Yellowstone National Park, and University of Utah to strengthen the long-term monitoring of volcanic and earthquake unrest in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.
Real-time Monitoring Information is available on the YVO Monitoring pages
For more information about the Volcano Alert Level and Aviation Color Code, please see the USGS Volcanic Activity Alert-Notification System web page.
