Volcano Update from Archive



ALASKA VOLCANO OBSERVATORY INFORMATION STATEMENT
Tuesday, June 26, 2012 12:56 PM AKDT (Tuesday, June 26, 2012 2056 UTC)


Spurr Volcano
61°17'56" N 152°15'14" W, Summit Elevation 11070 ft (3374 m)
Current Volcano Alert Level: Normal
Current Aviation Color Code: GREEN

On June 25, at approximately 5:00 AM AKDT (13:00 UTC), a minor increase in seismicity occurred at Mount Spurr and was observed during a routine check of seismic data at 11:00 AM AKDT (19:00 UTC). The character of the seismicity recorded at station CKN is consistent with the seismic energy generated by an energetic flow of water, possibly a glacier outburst flood on the lower south flank of Mount Spurr. The flow was a single event lasting about 45 minutes and was associated with several discrete shallow earthquakes up to magnitude 1 in size. As of this morning, seismic levels have declined to near background and no additional flowage signals have been observed; however, visitors to the area are advised to use caution if in or around the drainages on the south flank of Mount Spurr, especially those draining Kidazgeni glacier, and the Chakachatna River east of Kidazgeni Creek. A similar event occurred on June 29, 1993.



Mount Spurr volcano is an ice- and snow-covered stratovolcano located on the west side of Cook Inlet approximately 120 km (75 mi) west of Anchorage. The only known historical eruptions occurred in 1953 and 1992 from the Crater Peak flank vent located 3.5 km (2 mi) south of the summit of Mount Spurr. These eruptions were brief, explosive, and produced columns of ash that rose up to 20 km (65,000 ft) above sea level and deposited several mm of ash in south-central Alaska, including approximately 6 mm of ash on Anchorage in 1953. The last known eruption from the summit of Mount Spurr was more than 5,000 years ago. Primary hazards during future eruptions include far-traveled ash clouds, ash fall, pyroclastic flows, and lahars or mudflows that could inundate drainages all sides of the volcano, but primarily on the south and east flanks.

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

RECORDING ON THE STATUS OF ALASKA'S VOLCANOES (907) 786-7478

CONTACT INFORMATION:
John Power, Scientist-in-Charge, USGS

jpower@usgs.gov (907) 786-7497

or

Steve McNutt, Coordinating Scientist, UAF-GI

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.