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The Alaska Volcano Observatory (AVO) is a joint program of the U.S. Geological Survey (USGS), the Geophysical Institute of the University of Alaska Fairbanks (UAFGI), and the State of Alaska Division of Geological and Geophysical Surveys (ADGGS).
Great Sitkin
Color Code YELLOW / Alert Level ADVISORYvolcano image
Full details ...
Color Code YELLOW / Alert Level ADVISORYvolcano image
Full details ...

The Alaska Volcano Observatory’s summer 2020 field work plans
Posted: June 25, 2020
Starting the summer of 2019, the Alaska Volcano Observatory (AVO) began a three-year initiative to upgrade our volcano-monitoring network, by converting remaining analog seismic stations and telemetry to digital technology. Because of the remote locations of many of the stations, AVO, through our cooperative agreement with the Alaska Division of Geological and Geophysical Surveys (ADGGS), contracted a 108-ft-long research vessels R/V Steadfast, which has a helipad, and plentiful storage, lab, and berthing space for AVO crews to perform the necessary work. A contracted helicopter works from this moving platform to transport crews and equipment from the vessel to each site that is to be upgraded.

In 2019, upgrades were completed successfully at 45 stations and focused on networks around Adak (Gareloi, Tanaga, Kanaga, and Great Sitkin) and on Atka Island. In 2020, we planned for another ambitious season, including upgrades to our most remote networks in the western Aleutians, as well as a major upgrade to our satellite receive facility on Amchikta Island. In addition to upgrades, routine maintenance of equipment must proceed so that the entire monitoring network remains operational. 2020 field work was planned to start in late April at data-receive facilities, with vessel-based work slated to start in late May.

In light of COVID-19, we had to make changes to the scheduled work, due to timing, logistical constraints, and our desire to protect crews and the remote communities in the Aleutian island chain. We have postponed the far western Aleutians work, hoping to accomplish it in 2021. Our new vessel-based field schedule has work starting in mid-July and will focus on maintenance and upgrades in Cook Inlet, on the Alaska Peninsula, Unimak Island, and as far west as Dutch Harbor and possibly Umnak Island (home to frequently active Okmok volcano). The schedule has been reconfigured to minimize community interactions, and we developed a risk mitigation plan for the work following guidance from USGS, State of Alaska, and other organizations performing similar work (e.g., the University-National Oceanographic Laboratory System, or UNOLS, consortium). This change to our schedule drops the total number of vessel days from 88 to 54, and the planned number of analog-to-digital upgrades from 24 to 13. We also have helicopter-based geologic field investigations that are tentatively scheduled to proceed in August or September in the Cook Inlet and Wrangell areas.

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U.S. Geological Survey
Sunday, September 20, 2020, 11:38 AM AKDT (Sunday, September 20, 2020, 19:38 UTC)

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 earthquake activity was detected over the past day. Cloudy conditions obscured views of the volcano by satellite and web camera.

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

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

The local seismic network went gone down yesterday afternoon due to local storm activity and is expected to become operational again later today. No activity however, was detected on the regional infrasound nework. Cloudy conditions obscured views of the volcano by satellite.

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.


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/

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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.
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Page modified: February 21, 2020 14:16
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