Posted on 11/29/2005 8:37:52 PM PST by Strategerist
AUGUSTINE VOLCANO (CAVW#1103-01-) 59.3633°N 153.4333°W, Summit Elevation 4134 ft (1260 m) Current Level of Concern Color Code: YELLOW Previous Level of Concern Color Code: GREEN
AVO has detected important changes in earthquake activity and ground deformation at Augustine Volcano in southern Cook Inlet. These data are consistent with renewed volcanic unrest. AVO is therefore raising the level-of-concern color code from green to YELLOW and will continue to monitor activity closely. There is no indication that an eruption is imminent or certain.
Beginning in May 2005, there has been a slow increase in the number of earthquakes located under Augustine Volcano. The earthquakes are generally small (less than magnitude 1.0) and concentrate roughly 1 km below the volcano's summit. These earthquakes have slowly increased from 4-8 earthquakes/day to 20-35 earthquakes/day. Additionally, data from a 6-station Global Positioning System (GPS) network on Augustine Volcano indicate that a slow, steady inflation of the volcano started in mid-summer 2005 and continues at present. The GPS benchmark located nearest the summit has moved a total of 2.5 cm (1 inch). This motion is consistent with a source of inflation or pressure change centered under the volcano. This is the first such deformation detected at Augustine Volcano since measurements began just prior to the 1986 eruption.
No reports of increased steaming have been received by AVO, nor have satellite data shown increased thermal activity.
Historic eruptions of Augustine typically begin with explosive bursts that may send plumes of ash to 30,000-40,000 feet above sea level. The primary hazards to communities, aviation, and mariners in Cook Inlet and parts of south-central Alaska from an Augustine eruption are ash fall and drifting ash clouds. In 1986, 6 mm (0.25 inch) of ash fell in Homer, 120 km (75 mi) east of Augustine and light ashfall was recorded in Anchorage, 290 km (180 mi) away. Hot, ground-hugging flows of volcanic rock debris called pyroclastic flows may form during an eruption and could be hazardous to people, aircraft, or boats on or in the immediate vicinity of the island.
Island volcanoes can generate tsunamis by collapse into the sea. There is no evidence that conditions are developing that would lead to a major volcanic landslide or similar event at Augustine that, upon entering Cook Inlet, could generate a tsunami. No tsunami waves were generated during any of the last five eruptions of Augustine Volcano.
The full hazard assessment for Augustine Volcano can be obtained at http://www.avo.alaska.edu/pdfs/augustine_ofr.pdf
Augustine Volcano is a 1260 m high (4134 ft) conical-shaped stratovolcano located on Augustine Island in southern Cook Inlet, about 290 km (180 mi) southwest of Anchorage, Alaska. Augustine is the most historically active volcano in the Cook Inlet region. Historical eruptions occurred in 1812, 1883, 1908, 1935, 1963-64, 1976, and 1986. These eruptions were primarily explosive events that produced volcanic ash clouds and pyroclasic flows. During the 1883 eruption, a volcanic rock avalanche occurred on the north flank of the volcano; it flowed into Cook Inlet and initiated a tsunami observed at Nanwalek, about 90 km to the east.
ABBREVIATED COLOR CODE KEY (contact AVO for complete description): GREEN volcano is dormant; normal seismicity and fumarolic activity occurring 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
VOLCANO INFORMATION ON THE INTERNET: http://www.avo.alaska.edu RECORDING ON THE STATUS OF ALASKA'S VOLCANOES (907) 786-7478
CONTACT INFORMATION: Tom Murray, Scientist-in-Charge, USGS tlmurray@usgs.gov (907) 786-7497
John Eichelberger, Coordinating Scientist, UAF-GI eich@gi.alaska.edu (907) 474-5530
The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.
Both volcanoes erupt often and there's really no massive horrible deadly disaster potential, the worst case scenario is really a long-term disruption of flights into Anchorage due to ash (which would be a severe economic impact there) and possible need to re-route trans-Pacific air traffic.
A lot of greenhouse gases - the EPA should ban volcanoes.
Wow, three whole minutes till the first tired, dumb volcano-greenhouse gas emission joke....I thought it would be faster.
A lot of volcano activity right now, if I'm not mistaken.
all I want to know is - can they use this as an excuse to raise gas prices?
Bush's Fault!
Now that Hurricane season is officially over in a few hours, I guess we can start the Volcano watch live thread.
Put me on the ping list. LOL!
This histogram shows the number of earthquakes located within 8 km of the summit of Augustine Volcano between January 1, 1995 and November 27, 2005. Note that the current increase began in early May 2005. The current rate of earthquake activity observed at Augustine is well below that seen prior to the last eruption in 1986.
A closer view from a plane of the northern part of Mt. St. Augustine located in the Cook Inlet of Alaska. The view is to the east-southeast from the plane. In the photo the large debris flow fan deposit on the northern flank of the volcano is visible along with some lava flows on the upper flanks of the edifice. Picture Date: July 31, 2003 15:00:50
vigorous eruption column rising over the summit of 1,282-m (4,206 ft)-high Augustine Volcano. Steam can be seen rising from the margins of the summit crater. U.S. Geological Survey photograph, March 27, 1986.
Quick, somebody tell Ted Stevens so he can use our money to build a bridge to study this volcano.
Count on it.
Your attitude sucks, sir.
If you are that worried about, "tired, dumb volcano-greenhouse gas emission" jokes - why the hell did you post the article?
What, you think the audience is a bunch of geologists?
Thanks for the post but if, in the future, you think you will get comments that YOU do not like........
don't post it.
Now go find an attitude adjustment somewhere.
LVM
St Augustine Seismograph, Looks like something is happening 12/06/05.
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