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


U.S. Geological Survey
Friday, March 16, 2012, 12:44 PM AKDT (Friday, March 16, 2012, 20:44 UTC)

60°1'55" N 153°5'30" W, Summit Elevation 10016 ft (3053 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

Seismic activity at Iliamna Volcano remains above background. During the past week, small earthquakes continued to occur below the general vicinity of the volcano at depths mostly less than 4 km (2.5 miles) below sea level. Additional small and shallow earthquakes that may reflect movement of ice and other surface processes are also being recorded.

On several satellite images this week, a plume extended up to 35 miles downwind from the summit area of the volcano; the composition of this plume is uncertain but likely dominated by water vapor. Long-lived fumaroles at the summit of Iliamna frequently produce visible plumes; this week's plumes appear to be more robust than normal. A flight to measure levels of gas emission and make visual observations of the summit area is awaiting a favorable weather window.

The current activity at Iliamna does not indicate an imminent or certain eruption. A similar seismic swarm at Iliamna in 1996-1997 was not followed by eruptive activity. Prior to an eruption, AVO would expect to see a further increase in earthquake activity.

During the past week, AVO field engineers conducted maintenance on seismic station communication systems on the Kenai Peninsula to improve signal strength. The AVO web camera on Platform Anna was repositioned to show Iliamna Volcano and planning is underway to install an additional web camera.

Iliamna volcano is located on the western side of lower Cook Inlet in the Lake Clark National Park. The volcano has a summit altitude of 3053 m (10,016 feet) above sea level and the volcano supports an extensive cover of snow and glacier ice. An active fumarole field is present on the upper eastern face of the volcano and on calm days, vapor emissions are often visible. There have been no known historical eruptions of Iliamna Volcano, but volcanic deposits on the flanks of the volcano indicate that there have been multiple explosive eruptions in the past 2500 years. The most recent explosive eruption occurred about 300 years ago. Occasional large ice and rock avalanches, and changes in glacial ice are common at this steep and rugged volcano. The volcano is located 210 km (130 miles) southwest of Anchorage and 100 km (60 miles) northwest of Homer.

Additional information:

Iliamna Web Page


Iliamna Web Camera


Preliminary volcano-hazard assessment for Iliamna Volcano, Alaska


VOLCANO INFORMATION ON THE INTERNET: http://www.avo.alaska.edu



Seismic activity is monitored in real time at 29 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, Isanotski, Kanaga, Katmai, Mageik, Makushin, Martin, Novarupta, Okmok, Pavlof, Redoubt, Shishaldin, Snowy, Spurr, Tanaga, Trident, Ugashik-Peulik, Ukinrek Maars, Veniaminof, and Westdahl 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 of these volcanoes.

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

52°49'20" N 169°56'42" W, Summit Elevation 5676 ft (1730 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Cleveland Volcano continues to erupt at a low level. Three small explosions have occurred at Cleveland during the past nine days (March 8, 10, and 13). These events were detected on distant infrasound and seismic networks, but none produced a detectable ash cloud suggesting very minor ash production. It is likely that these small explosions expelled any lava that occupied the summit crater at Cleveland.

Prior to this March activity, several small explosions were also detected in December 2011. An event on December 29 produced a small ash cloud that rose about 15,000 feet above sea level and drifted out over the North Pacific. The onset of explosive activity in December followed about a four-month period of slow, intermittent effusion of lava into the summit crater.

While the volcano remains in this active state, more sudden explosions of blocks and ash are likely. It is possible for associated ash clouds to exceed 20,000 feet above sea level. If a larger ash-producing event occurs, seismic, infrasound, or volcanic lightning networks should detect the event and alert AVO staff. There is no real-time seismic monitoring network on Mount Cleveland so AVO is unable to track activity in real time.

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. In February 2001, three explosive events produced ash clouds as high as 12 km (39,000 ft) above sea level. The 2001 eruption also produced a rubbly lava flow and hot avalanche that reached the sea. Since 2001, the volcano has intermittently produced relatively small short-lived ash clouds. The current pattern of lava effusion into the summit crater and intermittent explosive destruction of the resulting lava dome began in July of 2011.

Additional information:

Cleveland Web Page

VOLCANO INFORMATION ON THE INTERNET: http://www.avo.alaska.edu


John Power, Scientist-in-Charge, USGS
jpower@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: www.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 G22AC00137

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