Volcanic Activity ReportEarth Changes News |
The alert-level system for all volcanoes monitored by the USGS was changed on 1 October from a numerical system to a descriptive system. In the new system, alert-level Normal indicates background conditions and is equivalent to aviation color-code Green. The previous alert levels of Volcanic Unrest (Alert Level 1), Volcano Advisory (Alert Level 2) and Volcano Alert (Alert Level 3) have changed to "Advisory," "Watch," and "Warning," respectively. There is a subtle change to the aviation color-code definitions in that there is no longer an ash-plume threshold given for either Orange or Red. Watch; Aviation color code ORANGE." The alert-level "Watch" is used for two different situations: (1) heightened or escalating unrest indicating a higher potential that an eruption is likely, but still not certain; or (2) an eruption that poses only limited hazard.
ABBREVIATED COLOR CODE KEY :
GREEN volcano is dormant; normal seismicity and fumarolic activity occurring = Normal
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected at any time
ICELAND - Eyjafjallajökull volcano
June 19th, 2010
Update 17th of June from IMO - There is a wall of ice at the eastern, southern and western sides of the crater lake. On the northern side a tephra wall rises 20 meters above the water. The ice walls at the southwestern corner of the crater are melting, i.e. at the site of the vent that was active 4 - 6 June. The rate of melting is assumed to be about one cubic meter per second. Update 11th of June - Scientists flew over Eyjafjallajökull on the morning and saw that a lake has formed in the crater. Possibly, some degassing of magma still occurs in a small path located at the western or soutwestern rim of the crater, see brownish veils at the right hand side of the photograph below. Steam rises from the surface of the water, mostly at the northern edge.
RUSSIA - Bezymianny volcano (Kamtchatka)
June 19th, 2010
As of the 18th of June, the Kamchatkan Volcanic Eruption Response Team (KVERT) reported that of the volcano continues and aerosol plumes could affect low-flying aircraft.
RUSSIA - Sheveluch volcano ( Kamchatka)
June 19th, 2010
As of the 18th of June, the Kamchatkan Volcanic Eruption Response Team (KVERT) reported that explosive-extrusive eruption of the volcano continues. Seismicity was above background levels. According to seismic data, possibly ash plumes rose up to 4.9 km (16,100 ft) ASL all week.
RUSSIA - Karymsky volcano (Kamchatka)
June 19th, 2010
As of the 18th of June, the Kamchatkan Volcanic Eruption Response Team (KVERT) reported that explosive activity of the volcano continues. Ash explosions >6.0 km (>19,700 ft) ASL could occur at any time. Aactivity of the volcano could affect low-flying aircraft. Seismic activity of the volcano was above background levels all week.
RUSSIA - Kliuchevskoy volcano (Kamchatka)
June 19th, 2010
As of the 18th of June, the Kamchatkan Volcanic Eruption Response Team (KVERT) reported that explosive-effusive eruption of the volcano continues. Ash explosions >7.0 km (>23,000 ft) ASL could occur at any time. The activity of the volcano could affect international and low-flying aircraft. Seismicity of the volcano was above background levels all week
Scientists are using infrared images to track potentially deadly patterns of heat in the Earth in and around active volcanoes. One aim: to save lives by predicting eruptions.
Giant Undersea Volcano Found Off Iceland
National Geographic News - April 22, 2008: A giant and unusual underwater volcano lies just offshore of Iceland on the Reykjanes Ridge, volcanologists have announced. The Reykjanes formation is a section of the Mid-Atlantic Ridge, which bisects the Atlantic Ocean where the North American and Eurasian tectonic plates are pulling apart.
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ScienceDaily (Dec. 3, 2009) - Hawaii may be paradise for vacationers, but for geologists it has long been a puzzle. Plate tectonic theory readily explains the existence of volcanoes at boundaries where plates split apart or collide, but mid-plate volcanoes such as those that built the Hawaiian island chain have been harder to fit into the theory. A classic explanation, proposed nearly 40 years ago, has been that magma is supplied to the volcanoes from upwellings of hot rock, called mantle "plumes," that originate deep in the Earth's mantle. Evidence for these deep structures has been sketchy, however. Now, a sophisticated array of seismometers deployed on the sea floor around Hawaii has provided the first high-resolution seismic images of a mantle plume extending to depths of at least 1,500 kilometers (932 miles).
January 2010 Proclaimed Volcano Awareness Month - January 3, 2010, marks the 27th anniversary of K?lauea's ongoing east rift zone eruption. In 2010, it will also be 20 years since Kalapana was buried beneath lava and 50 years since Kapoho was inundated by fast-moving lava flows. The destruction of these two communities is a sobering reminder of why it's important to understand how Hawai'i's volcanoes work.
Volcanoes are integral to life on Hawai'i Island. Volcanoes provide the soils in which we grow coffee, macadamia nuts, and other agricultural products, and supply energy for our electricity. When they erupt, they can be spectacularly beautiful, mesmerizing both residents and visitors who are lucky enough to witness the drama.
Volcanoes were so significant to early Hawaiian settlers that an entire theology-the goddess Pele and her family-was founded on them. Today, as in the past, awareness is essential for us to live in harmony with the volcanoes that make our island home.
HAWAIIAN VOLCANO OBSERVATORY UPDATE
KILAUEA VOLCANO (CAVW #1302-01-)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Aviation Color Code: ORANGE
Current Volcano Alert Level: WATCH
June 19th, 2010 - As of the 18th of June, the Hawaiian Volcano Observatory (HVO) reported that Kilauea volcanic activity continued with lava ponds at two locations. The summit eruptive vent within Halema`uma`u Crater hosted a crusted and circulating lava pond that produced red glow visible from the Jaggar Museum overnight. Pu`u `O`o Crater, in the east rift zone, hosted an active perched lava pond; in addition, lava flowed from the TEB vent through tubes to supply a rootless shield field above the pali. Sulfur dioxide emission rates from the summit and east rift zone vents remained elevated.
Summary - The Pu`u `O `o-Kupaianaha eruption of Kilauea, now in its twenty-fourth year and 55th eruptive episode, ranks as the most voluminous outpouring of lava on the volcano's east rift zone in the past five centuries. By January 2007, 3.1 cubic km of lava had covered 117 km2 and added 201 hectares to K?lauea's southern shore. In the process, lava flows destroyed 189 structures and resurfaced 14 km of highway with as much as 35 m of lava.
Beginning in 1983, a series of short-lived lava fountains built the massive cinder-and-spatter cone of Pu`u `? `?. In 1986, the eruption migrated 3 km down the east rift zone to build a broad shield, Kupaianaha, which fed lava to the coast for the next 5.5 years.
When the eruption shifted back to Pu`u `O `o in 1992, flank-vent eruptions formed a shield banked against the west side of the cone. From 1992 to 2007, nearly continuous effusion from these vents has sent lava flows to the ocean, mainly inside the national park. Flank vent activity undermined the west and south sides of the cone, resulting in the collapse of the west flank in January 1997.
Since 1997, the eruption has continued from a series of flank vents on
the west and south sides of the Pu`u `O `o cone. During this time the composite
flow field has expanded westward, and tube-fed pahoehoe forms a plain that
spans 15.6 km at the coast.
HAZARD ALERT: The lava delta and adjacent areas both inland and out to sea are some of the most hazardous areas on the flow field. Frequent delta/bench collapses give little warning, can produce hot rock falls inland and in the adjacent ocean, and can produce large but local waves. The steam plume produced by lava entering the ocean contains fine lava fragments and an assortment of acid droplets that can be harmful to your health. The rapidly changing conditions near the ocean entry have been responsible for many injuries and a few deaths.
Maps, photos, webcam views, and other information about Kilauea Volcano are available at http://volcanoes.usgs.gov/hvo/activity/kilaueastatus.php. A daily update summary is available by phone at (808) 967-8862.
A map with details of earthquakes located within the past two weeks can be found at http://tux.wr.usgs.gov/
A definition of alert levels can be found at http://volcanoes.usgs.gov/activity/alertsystem/index.php
The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawai`i.
Definitions of terms used in the update:
HAVO: Hawai`i Volcanoes National Park
UHH: University of Hawai`i at Hilo
glow: light from an unseen source; indirect light.
FLIR: Forward Looking InfraRed, a camera which directly images heat rather than visible light. If volcanic fume is not too rich in water vapor, a FLIR can see through it to image hot surfaces.
pali: Hawaiian word for cliff or steep incline. In the context of the TEB flow field, 'pali' usually refers to Pulama pali that bisects the abandoned Royal Gardens subdivision.
CD: Hawai`i County Civil Defense
DOH air quality monitoring: see Hawai`i State Department of Health Air Quality website http://hawaii.gov/doh/air-quality/index.html .
bomb: lava fragment ejected into the air while molten acquiring aerodynamic shapes in flight; the term is restricted to pieces larger than 6.4 cm (2.5 in.). See http://volcanoes.usgs.gov/Products/Pglossary/bomb.html
hybrid, or explosion, seismic signals: complex earthquakes that are a hybrid of different signals. They start as a high frequency earthquake, similar to typical rock-breaking or rock fall events, that transitions to very long, 20-30 second, period (VLP) oscillations that continue for several minutes. At HVO, we observed these signals with the four small Halema`uma`u explosive eruptions in March, April, and August 2008. Several more similar signals, some as strong as the explosion signals associated with the four explosive eruptions, have been recorded without obvious evidenceof surface eruption such as rock fragments or other debris.
MODIS satellite: a NASA satellite pair, Aqua and Terra, which passes over Hawai`i twice a day. During daylight hours, the images are taken at about 11 am and 2 pm H.s.t. This imagery can be viewed about 3-5 hours after acquisition at http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=AERONET_Mauna_Loa.
GOES-WEST satellite: a geostationary NOAA satellite used most often for weather tracking. Images are typically acquired every 15 minutes. The loop http://www.ssd.noaa.gov/VAAC/kilauea/sloop-vis.html is posted by the Washington DC Volcanic Ash Advisory Center for the purpose of tracking emissions from Hawai`i volcanoes. The imagery automatically switches from infrared at night to visual during the day. Recently, it has been useful for tracking volcanic gas emissions from Halema`uma`u, Pu`u `O`o, and the Waikupanaha ocean entry during the day and hot lava flows at night.
Volcano Watch: weekly newspaper-like article written by HVO scientists on a volcano topic of interest. These articles are usually printed in the Sunday editions of the Hawai`i Island newspapers Hawaii Tribune Herald and West Hawaii Today. More than 800 of these articles have been written and are archived on the HVO website (menu at the bottom of the homepage hvo.wr.usgs.gov).
VLP seismic tremor: seismic tremor is continuous ground vibrations simultaneously at many different frequencies. VLP is a very long period or very low frequency component which, at the Halema`uma`u vent, has a period of 20-30 seconds or a frequency of 0.03-0.05 cycles per second (Hertz or Hz).
RB2S2BL earthquakes: earthquakes that were recorded but were too small to be located. These quakes have magnitudes less than 1.7 and may only be recorded by one or two seismometers. Recording at a minimum of 4 seismometer sites is required to locate an earthquake.
wink: an abrupt shutting off of incandescence at a vent lasting for several minutes. At the Halema`uma`u vent, winks usually start with or immediately follow a small, local earthquake. The diminishment of incandescence is due to the plume changing from translucent to opaque with rock dust.
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
microradian: a measure of angle equivalent to 0.000057 degrees.
ppm: parts-per-million; 10,000 ppm = 1 %.
littoral cone: usually small cones built near active ocean entries; the cones are constructed of tephra from steam explosions that are sometimes produced when 1,150 degree C lava enters the 25 degree C ocean.
incandescence: the production of visible light from a hot surface. The term also refers to the light emitted from a hot surface. The color of the light is related to surface temperature. Some surfaces can display dull red incandescence at temperatures as low as 430 degrees Centigrade (806 degrees Fahrenheit). By contrast, molten lava displays bright orange to orange-yellow light from surfaces that are hotter than 900 degrees C (1,650 degrees F).
tephra: all material deposited by fallout from an eruption-related plume, regardless of size.
ash: tephra less than 2 mm (5/64 inches) in size.
TEB: Thanksgiving Eve Breakout, the designation used for lava flows that started with a breakout on November 21, 2007.
DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a volcanic event of uncertain significance. DI events are recorded by tiltmeters at Kilauea summit as an abrupt deflation of up to a few microradians in magnitude lasting several hours to 2-3 days followed by an abrupt inflation of approximately equal magnitude. The tilt events are usually accompanied by an increase in summit tremor during the deflation phase. A careful analysis of these events suggests that they may be related to changes in magma supply to a storage reservoir at less than 1 km depth, just east of Halema`uma`u crater. Usually, though not always, these changes propagate through the magma conduit from the summit to the eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by 1-2 hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
Maps, photos, webcam views, and other information about Kilauea Volcano are available at http://volcano.wr.usgs.gov/kilaueastatus.php. A daily update summary is available by phone at (808) 967-8862.
A map with details of earthquakes located within the past two weeks can be found at http://tux.wr.usgs.gov
Listen to a podcast interview with Dr. Eichelberger describing the activity at Kilauea in episode 35 of CoreCast at http://www.usgs.gov/corecast/.
21-Nov-2006: Volcanic eruptions in high latitudes can greatly alter climate and distant river flows, including the Nile, according to a recent study funded in part by NASA. Researchers found that Iceland's Laki volcanic event, a series of about ten eruptions from June 1783 through February 1784, significantly changed atmospheric circulations across much of the Northern Hemisphere. This created unusual temperature and precipitation patterns that peaked in the summer of 1783, including far below normal rainfall over much of the Nile River watershed and record low river levels. Full Article Here
ScienceDaily (Dec. 14, 2009) - The most detailed seismic images yet published of the plumbing that feeds the Yellowstone supervolcano shows a plume of hot and molten rock rising at an angle from the northwest at a depth of at least 410 miles, contradicting claims that there is no deep plume, only shallow hot rock moving like slowly boiling soup.
The Journal of Volcanology and Geothermal Research recently (20 November 2009) published a special volume on the track of the Yellowstone Hot Spot.
Listing of articles for preview and purchase
By Andrea Thompson, LiveScience Staff Writer: 08 November 2007 02:00 pm ET
Yellowstone's ancient volcanic floor has been rising since mid-2004 because a blob of molten rock the size of Los Angeles infiltrated the system 6 miles beneath the surface, scientists say, but there is no risk of an eruption.
Yellowstone National Park is the site of North America's largest volcanic field, which is produced by a hotspot, or gigantic plume of hot, molten rock, that begins at least 400 miles (643 kilometers) beneath Earth's surface and rises to 30 miles (48 kilometers) underground, where it widens to about 300 miles across.
Updates are compiled for the previous month and posted in the first week of the new month.
44°25'48" N 110°40'12" W, Summit Elevation 9203 ft (2805 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN
During the month of May 2010, 118 earthquakes were located in the Yellowstone region. The largest event was a magnitude 2.5 on May 11th at 9:31 AM MDT, located about 11 miles west of Fishing Bridge, YNP. No earthquake swarms were recorded during May and seismicity continues at background levels.
Ground Deformation Summary: Continuous GPS data show that uplift of the Yellowstone Caldera has slowed significantly and have have stopped in some areas. The WLWY station, located in the northeastern part of the caldera, underwent a total of ~23 cm of uplift between mid-2004 and mid-2009. Its record can be found at:
http://pboweb.unavco.org/shared/scripts/stations/?checkkey=WLWY&sec=timeseries_plots×eries=raw
The general uplift and subsidence of the Yellowstone caldera is of scientific importance and will continue to be monitored closely by YVO staff.
An article on the recent 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
Monday, March 1, 2010
February 2010 Yellowstone Seismicity Summary: During the first half of February 2010, Yellowstone continued to experience a large swarm of earthquakes on the Madison Plateau, near the northwest margin of the Yellowstone Caldera. Retrospective analysis shows that the swarm began on January 15, 2010 and picked up in intensity on the 17th of January. As of February 25, a total of 1,809 earthquakes had been automatically located for the entire swarm, including 14 with a magnitude greater than 3.0; 136 with M2.0-2.9; 1,119 with M1.0-1.9; and 540 with M0.0-0.9. By the end of February 2010, earthquake activity at Yellowstone had returned to near-background levels.
Within the entire Yellowstone National Park region, 244 earthquakes received review by a seismologist during February. The largest event was a magnitude 3.1 on Feb. 2 at 7:31 PM MST. This earthquake was part of the Madison Plateau swarm and was located 7 miles SSE of Madison Junction, WY. In addition a small earthquake swarm of 17 earthquakes occurred on February 13, and was located about 12 miles NE of West Yellowstone, MT, with magnitudes ranging from -0.2 to 1.6. Some of the smallest events from the Madison Plateau swarm remain to be reviewed by a seismologist, and so the 244 earthquake tally is provisional.
Ground Deformation Summary: Continuous GPS data show that uplift of the Yellowstone Caldera has slowed significantly. Uplift rates for YVO GPS stations are less than 2.5 cm per year. The WLWY station, located in the northeastern part of the caldera, underwent a total of ~23 cm of uplift between mid-2004 and mid-2009. Its record can be found at:
http://pboweb.unavco.org/shared/scripts/stations/?checkkey=WLWY&sec=timeseries_plots×eries=raw
The general uplift and subsidence of the Yellowstone caldera is of scientific importance and will continue to be monitored closely by YVO staff.
An article on the recent 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
Summary of January - February 2010 Yellowstone Earthquake Swarm- The rate of earthquake occurrence in the Madison Plateau area is now at background levels. The swarm began on January 17, 2010 around 1:00 PM MST about 10 miles (16 km) northwest of the Old Faithful area on the northwestern edge of Yellowstone Caldera. Swarms have occurred in this area several times over the past two decades.
As of February 8, 2010 14:00 MST, there have been 1799 events recorded by the automatic earthquake system of the University of Utah. Of those, 827 have been verified by seismic analysts and forwarded to the National Earthquake Information Center (NEIC) for incorporation in the permanent listing of earthquakes. Seismologists of the University of Utah will continue to analyze data from the past several weeks to finalize the earthquake information.
The largest events were a pair of earthquakes of magnitude 3.7 and 3.8 that occurred after 11 PM MST on January 20, 2010. Both events were felt throughout the park and in surrounding communities in Wyoming, Montana, and Idaho. Other smaller events were also reported as felt.
The earthquakes were on the Madison Plateau along the northwest side of the Yellowstone caldera, in an area where previous swarms had occurred over the past 30 years. Visual observation of landforms and geothermal features by Yellowstone National Park personnel did not show any changes that could be attributed to the earthquakes.
Yellowstone National Park is in a region of active seismicity associated with regional Basin and Range extension of the Western U.S., as well as youthful volcanism of the Yellowstone volcanic field. Pressurization due to crustal magma bodies of the Yellowstone hotspot and associated shallow geothermal reservoirs can also contribute to earthquakes. Scientists will continue to research the origin of these and other Yellowstone earthquakes.
Any new information will be posted to: http://volcanoes.usgs.gov/yvo/activity/index.php
A summary of the swarm and links to additional information can be found at: http://volcanoes.usgs.gov/yvo/publications/2010/10swarm.php
Seismic information on the earthquake can be viewed at the University of Utah Seismograph Stations: http://www.seis.utah.edu/
Seismograph recordings from stations of the Yellowstone seismograph network can be viewed online at: http://quake.utah.edu/helicorder/yell_webi.htm
Ground Deformation Summary: Continuous GPS data show that uplift of the Yellowstone Caldera has slowed significantly and may have stopped. The WLWY station, located in the northeastern part of the caldera, underwent a total of ~23 cm of uplift between mid-2004 and mid-2009. Its record can be found at:
http://pboweb.unavco.org/shared/scripts/stations/?checkkey=WLWY&sec=timeseries_plots×eries=raw
The general uplift and subsidence of the Yellowstone caldera is of scientific importance and will continue to be monitored closely by YVO staff.
An article on the recent 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 currently observed reduction in uplift rate may be related to seasonal changes related to snowmelt and groundwater recharge. In several of the past 5 years, such changes have caused decreased uplift or slight subsidence, but were followed later in the year by continued uplift. The general uplift of the Yellowstone caldera is of scientific importance 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
An article on the recent earthquake swarm during December 2008 and January 2009 can be found at:
http://volcanoes.usgs.gov/yvo/publications/2009/09swarm.php
Scientists continue to look at data collected during the swarm and will publish their results over the coming months and years. However, if any findings have direct implications for public safety, they will be released to the public immediately.
The Journal of Volcanology and Geothermal Research recently (20 November 2009) published a special volume on the track of the Yellowstone Hot Spot
Monday, February 2, 2009 10:52 MST (Monday, February 2, 2009 17:52 UTC)
Seismicity Summary: As of January 8, 2009, the seismic activity has markedly decreased. Beginning Dec 26, 2008, the second largest earthquake swarm of Yellowstone's recorded seismic history occurred beneath the north end of Yellowstone Lake. The swarm continued into Jan. 2009, but subsided rather quickly in activity on January 5. The Lake swarm consisted of 813 well-located earthquakes with magnitudes ranging from -0.8 to 3.9. This sequence contained 19 earthquakes of M>3.0 as well as 141 events of 2<M<2.9. Several of the M>3 swarm events were felt throughout Yellowstone National Park and surrounding area. For the entire month of January, 2009 315 earthquakes were located with 205 of these events associated with the Yellowstone Lake swarm, the largest being M 3.5 on January 2 at 11:32 AM MST. There have not been any reports of damage from the Yellowstone Lake swarm. Note that the largest earthquake swarm recorded in Yellowstone began in the autumn of 1985 on the west side of the caldera and east of West Yellowstone MT. It lasted for ~4 months and contained earthquakes of M>4.
In Jan. 9 to Jan 12, a secondary swarm of 35 earthquakes occurred near the northeast edge of the Yellowstone caldera, about 10 miles (16 km) NNE of the north end of the Yellowstone Lake swarm. This sequence included events with magnitudes of 0.4 to 3.3.
For comparison, Yellowstone commonly experiences 1,000 to 3,000 earthquakes per year and there have been more than 32,000 well-recorded earthquakes in Yellowstone from 1973 to 2009. Earthquakes that are closely spaced in time and area are termed swarms and are a common mode of seismic energy release in the Yellowstone caldera. From 1984 to 2008 there were 80 swarms documented in Yellowstone. The last notable swarm occurred in 2004.
Earthquake activity in the Yellowstone was elevated during the Yellowstone Lake swarm but has returned to relatively normal background levels.
Yellowstone Volcano Observatory partners continue to analyze the seismic and ground deformation data from the Yellowstone Lake swarm and are evaluating any changes to the thermal areas located near the epicenters. If any changes are to be verified, they are quite small.
Ground Deformation Summary: Through January 2009, continuous GPS data show that much of the Yellowstone caldera continued moving upward, though at a lower rate than the past several years. The nearest GPS station to the swarm, at Lake Jct., about 2 km from the swarm has experienced ground uplift over the past 55 months of about ~18 cm (A plot of the vertical and horizontal ground motions at the Lake GPS station can be found at: http://pboweb.unavco.org/shared/scripts/stations/?checkkey=LKWY&sec=timeseries_plots×eries=raw). The WLWY station has undergone ~21 cm of uplift over the same time period. These and all other Yellowstone GPS data are being analyzed for unusual properties that may be associated with the Yellowstone Lake swarm. The general uplift of the Yellowstone caldera is of scientific importance 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.
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.
Yellowstone Lake Earthquake Swarm Summary as of 8 January 2009
Image 1. Yellowstone Lake showing location and times of the recent earthquakes from Dec. 27, 2008 (blue) to Jan. 8, 2009 (red). The M 3.0 and greater earthquakes are shown as stars, the smaller earthquakes are shown as circles. During the swarm, the earthquake locations appear to have moved north. |
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
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.
Earthquake Magnitude ranging from barely felt into the 3.6 mag. range have been swarming since Dec. 26, 2008. On Jan. 1, 2009 there have been 241 earthquakes registering in this swarm at 44 degress North, 110 degrees West. For an updated list of this activity, click here.
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN
Activity Update: All volcanoes in the Cascade Range are at normal levels of background seismicity. These include Mount Baker, Glacier Peak, Mount Rainier, Mount St. Helens, and Mount Adams in Washington State; Mount Hood, Mount Jefferson, Three Sisters, Newberry Volcano, and Crater Lake, in Oregon; and Medicine Lake volcano, Mount Shasta, and Lassen Peak in northern California.
Mount St. Helens has been at Volcano Alert Level NORMAL (Aviation Color Code GREEN) since July 10, 2008.
Recent Observations: Cascade Range volcano seismicity and deformation remained at background levels during the past week. Field crews were at Mount St. Helens this week conducting routine maintenance at telecommunication and instrument sites. On Wednesday, 10 February, there were two short-duration earthquake swarms at Lassen Peak, CA. The largest event in the swarms was a M1.9 earthquake located west of Lassen Peak. Earthquake swarms are fairly common in the Lassen Peak area occurring several times per year.
For a webcam view of the volcano: http://www.fs.fed.us/gpnf/volcanocams/msh/
A
Volcano Rekindled: The Renewed Eruption of Mount St. Helens, 2004-2006 November 22, 2006
The current eruption of Washington State's Mount St. Helens, which began about two years ago, has been marked by a series of weak, shallow earthquakes, or "drumbeats," that occur every couple of minutes, a new study says. The "slip/stick" motion of the rocky "plug" being pushed out of the volcano is causing those rhythmic quakes, according to scientists from the Cascades Volcano Observatory in Vancouver, Washington
Oct. 3 , 2006: In June 1912, Novarupta-one of a chain of volcanoes on the Alaska Peninsula-erupted in what turned out to be the largest blast of the twentieth century.Almost a hundred years later, researchers are paying attention. Novarupta is near the Arctic Circle and its impact on climate appears to be quite different from that of "ordinary" tropical volcanoes, according to recent research by climatologists using a NASA computer model.
When a volcano anywhere erupts, it does more than spew clouds of ash, which can shadow a region from sunlight and cool it for a few days. It also spews sulfur dioxide. If the eruption is strongly vertical, it shoots that sulfur dioxide high into the stratosphere more than 10 miles above Earth.
Up in the stratosphere, sulfur dioxide reacts with water vapor to form sulfate aerosols. Because these aerosols float above the altitude of rain, they don't get washed out. They linger, reflecting sunlight and cooling Earth's surface.
This can create a kind of nuclear winter (a.k.a. "volcanic winter") for a year or more after an eruption. In April 1815, for instance, the Tambora volcano in Indonesia erupted. The following year, 1816, was called "the year without a summer," with snow falling across the United States in July. Even the smaller June 1991 eruption of Pinatubo in the Philippines cooled the average temperature of the northern hemisphere summer of 1992 to well below average.
But both those volcanoes as well as Krakatau were in the tropics.
Novarupta is just south of the Arctic Circle.
For Complete Story - http://science.nasa.gov/headlines/y2006/03oct_novarupta.htm
37°42' N 118°52'12" W, Summit Elevation 7231 ft (2204 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN
Friday, June 11, 2010
Twenty eight earthquakes with magnitudes ranging between M=1 and M=2.8 occurred in the Long Valley area since last week's update on June 4, 2010. Twelve of these earthquakes occurred in a cluster about 3 km (2 miles) east of the Town of Mammoth Lakes, including the largest event of the week, a M=2.8 at 3:40 PM (PDT) on June 7, 2010. The earthquake swarm near the southern end of the Mono Craters chain, which began two weeks ago, continued its slow decline in activity. Only four earthquakes occurred in this region, the largest being a M=1.7 late in the afternoon of June 4, 2010. Four earthquakes, including a M=1.9 at 7:07 AM (PDT) on 2010/06/09, occurred on the southeast flank of Mammoth Mountain, and two small (M<1.5) earthquakes occurred beneath the southern section of the resurgent dome. Five M>1 earthquakes occurred in the Sierra Nevada south of the caldera, the largest of which was a M=1.8 at 6:17 PM (PDT) on June 5, 2010.
Long Term Trends
Seismic Trend: Earthquake activity within and adjacent to the caldera has remained low since mid-1999 averaging just five to ten earthquake per day with magnitudes less than M=2 and an occasional event as large as M=3. see details.
Deformation trend: Renewed uplift of the resurgent dome that began in early 2002 ended in early 2003 largely offsetting the 2 cm of subsidence that accumulated from early 1999 through the end of 2001. The resurent dome has since shown minor fluctuations in uplift and subsidence but remains roughly 80 cm higher than in the late 1970's. see details.
CO2 trend: The diffuse carbon dioxide gas flux in the Horseshoe
Lake tree-kill area has shown little change from the relatively high levels
of 50 to 150 tons per day sustained for the past several years; see details.
