Alaska Volcano Observatory

RESTLESS VOLCANOES

Great Sitkin
Color Code YELLOW / Alert Level ADVISORY

Full details ...

Semisopochnoi
Color Code YELLOW / Alert Level ADVISORY

Full details ...

NEWS

Alaska Volcano Observatory Expands Eruption Detection Capability in Cook Inlet
Posted: October 15, 2020

Alaska Volcano Observatory staff completed the installation of a new monitoring station on the Kenai Peninsula in early October 2020 that improves our ability to detect, quantify, and study future explosive eruptions from volcanoes along the west side of Cook Inlet and on the Alaska Peninsula. The station is equipped with six sensors spaced 200-300' apart that work together to remotely detect low-frequency sound, or infrasound, from volcanic activity. Infrasound is sound at frequencies below what humans are capable of hearing and is produced when volcanoes erupt gas and ash into the atmosphere (https://avo.alaska.edu/about/infrasound.php). Infrasound from energetic volcanic eruptions can travel hundreds of miles from the source and still be recorded on sensitive infrasound microphones like the ones installed in the new AVO station. The design and location of this new station will allow AVO to use it to monitor multiple volcanoes because it can determine the direction from which infrasound signals originated. Infrasound is also not affected by darkness, cloud cover or precipitation, making this new station a 24/7 sentinel of volcanic unrest.

Station KENI - a 6 element infrasound array on the Kenai peninsula. The pyramid on the left of the hut is one of the infrasound sensors at the site. Photo by C. Read, USGS/AVO, Oct 1, 2020.

LAST ACTIVITY REPORT

Get these reports emailed to you: USGS VNS

ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Wednesday, October 21, 2020, 12:01 PM AKDT (Wednesday, October 21, 2020, 20:01 UTC)

GREAT SITKIN VOLCANO (VNUM #311120)
52°4'35" N 176°6'39" W, Summit Elevation 5709 ft (1740 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

No significant activity was noted on seismic networks, regional infrasound sensors, or in cloudy web camera and satellite images.

Great Sitkin volcano is monitored by local seismic and infrasound sensors, satellite data, web cameras, and remote infrasound and lightning networks.

SEMISOPOCHNOI VOLCANO (VNUM #311060)
51°55'44" N 179°35'52" E, Summit Elevation 2625 ft (800 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

No significant activity was noted on seismic networks, regional infrasound sensors, or in partly cloudy satellite data.

Semisopochnoi is monitored by local seismic sensors, satellite data, and regional infrasound and lightning detection instruments. An infrasound array on Adak Island may detect explosive emissions from Semisopochnoi with a slight delay (approximately 13 minutes) if atmospheric conditions permit.

OTHER ALASKA VOLCANOES

Information on all Alaska volcanoes is available at : http://www.avo.alaska.edu.

For definitions of Aviation Color Codes and Volcano Alert Levels, see: http://www.avo.alaska.edu/color_codes.php

SUBSCRIBE TO VOLCANO ALERT MESSAGES by email: http://volcanoes.usgs.gov/vns/

FOLLOW AVO ON FACEBOOK: https://facebook.com/alaska.avo

FOLLOW AVO ON TWITTER: https://twitter.com/alaska_avo

CONTACT INFORMATION:

Michelle Coombs, Scientist-in-Charge, USGS
mcoombs@usgs.gov (907) 786-7497

David Fee, Coordinating Scientist, UAFGI
dfee1@alaska.edu (907) 322-4085

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.