AVO Logo
Site Map | FAQ |
Alaska Volcano Observatory
Summary | Color Code Definitions | Webcams | Webicorders | RSAM | Activity Notifications | Notification Search | Cleveland | Semisopochnoi | Shishaldin | Veniaminof 
You are here: Home > Current Volcanic Activity

AVO VOLCANO ACTIVITY NOTIFICATION

ALASKA VOLCANO OBSERVATORY WEEKLY UPDATE
U.S. Geological Survey
Friday, March 6, 2009, 1:40 PM AKST (Friday, March 6, 2009, 22:40 UTC)


REDOUBT VOLCANO (VNUM #313030)
60°29'7" N 152°44'38" W, Summit Elevation 10197 ft (3108 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Redoubt Volcano remains in a restless state. The level of seismic activity has declined somewhat this week but is still above background levels. Seismic activity consists of small discrete earthquakes, and little to no volcanic tremor. There have been no significant earthquake swarms over the past week, and no new hydrologic or glaciologic events related to ice melt have occurred. Clouds have obscured views of the volcano by web camera and satellite most of the week.

AVO continues to monitor Redoubt closely and the observatory will be staffed 24 hours per day while the volcano is at an elevated level of unrest.


Heavily ice-mantled Redoubt volcano is located on the western side of Cook Inlet, 170 km (106 mi) southwest of Anchorage and 82 km (51 mi) west of Kenai, within Lake Clark National Park. Redoubt is a stratovolcano which rises to 10,197 feet above sea level. Recent eruptions occurred in 1902, 1966-68, and 1989-90. The 1989-90 eruption produced mudflows, or lahars, that traveled down the Drift River and partially flooded the Drift River Oil Terminal facility. The ash plumes produced by the 1989-90 eruption affected international air traffic and resulted in minor or trace amounts of ash in the city of Anchorage and other nearby communities.

OKMOK VOLCANO (VNUM #311290)
53°23'49" N 168°9'58" W, Summit Elevation 3520 ft (1073 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

AVO increased the Aviation Color Code to YELLOW and the Volcanic Alert Level to ADVISORY for Okmok volcano last Monday, March 2, 2009. Over the past week there have been short bursts of volcanic tremor at Okmok, but these have gradually declined in frequency and amplitude. The increase in seismicity over the past week was the first significant seismic activity at the volcano since the eruption in August 2008 ended and represents an increase above typical background activity. The increase in seismic activity observed this week does not necessarily indicate that an eruption will occur, or that an eruption is likely.

Clouds have obscured the volcano most of the week. Observations made during an aerial overflight on Tuesday, March 3, indicated nothing unusual.


Okmok volcano is a 6-mile-wide caldera that occupies most of the eastern end of Umnak Island, located 75 miles southwest of Dutch Harbor in the eastern Aleutian Islands. Okmok has had several eruptions in historic time typically consisting of ash emissions occasionally to over 30,000 feet ASL but generally much lower; lava flows crossed the caldera floor in 1945, 1958, and 1997.

The nearest settlement is Nikolski, population about 35, roughly 45 miles west of the volcano. A ranch caretaker family lives at Fort Glenn on the flank of the volcano about 6 miles east of the caldera rim.


CLEVELAND VOLCANO (VNUM #311240)
52°49'20" N 169°56'42" W, Summit Elevation 5676 ft (1730 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

AVO has received no reports of activity at Cleveland over the past week. Clouds have obscured views of the volcano by satellite all week. Past eruptions of Cleveland have developed quickly, and low-level ash emissions may occur with little or no warning.

Cleveland volcano forms the western half of Chuginadak Island, a remote and uninhabited island in the east central Aleutians. It is located about 75 km (45 mi.) west of the community of Nikolski, and 1500 km (940 mi.) southwest of Anchorage. The volcano's most recent significant eruption began in February, 2001 and had 3 explosive events that produced ash clouds as high as 12 km (39,000 ft) above sea level. This eruption also produced a rubbly lava flow and hot avalanche that reached the sea. The most recent minor ash emissions were observed in January 2009.

OTHER ALASKA VOLCANOES

Seismic activity is monitored in real time at 31 volcanoes in Alaska. Satellite images of all Alaskan volcanoes are analyzed daily for evidence of ash plumes and elevated surface temperatures. Some volcanoes may currently display anomalous behavior but are not considered to be at a dangerous level of unrest. Akutan, Aniakchak, Augustine, Dutton, Fisher, Fourpeaked, Gareloi, Great Sitkin, Griggs, Iliamna, Isanotski, Kanaga, Katmai, Korovin, Mageik, Makushin, Martin, Novarupta, Okmok, Pavlof, Shishaldin, Snowy, Spurr, Tanaga, Trident, Ugashik-Peulik, Ukinrek Maars, Veniaminof, Westdahl, and Wrangell volcanoes are in color code GREEN and volcano alert level Normal. All are at or near normal levels of background seismicity. AVO did not detect ash plumes or significant elevated surface temperatures in the vicinity of any volcano.

Please see http://www.avo.alaska.edu/color_codes.php for complete definitions of Aviation color codes and Volcano alert levels.

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

Steve McNutt, Coordinating Scientist, UAF
steve@giseis.alaska.edu (907) 474-7131

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.
Contact AVO Privacy Accessibility Information Quality FOIA
URL: avo.alaska.edu/activity/report.php
Page modified: December 2, 2016 10:12
Contact Information: AVO Web Team

twitter @alaska_avo
facebook alaska.avo
email Receive volcano updates by email: USGS VNS

This website is supported by the U.S. Geological Survey under Cooperative Agreement Grant G19AC00060 and G19AC00171.

Mention of trade names or commercial products does not constitute their endorsement by the U.S. Geological Survey.