Hazard Notification System (HANS) for Volcanoes


U.S. Geological Survey
Wednesday, January 22, 2020, 10:55 PM AKST (Thursday, January 23, 2020, 07:55 UTC)

51°52'1" N 178°1'37" W, Summit Elevation 4754 ft (1449 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

The USGS National Earthquake Information Center (NEIC) detected a large magnitude 6.2 earthquake 14 km east of Takawangha volcano and 22 km east of Tanaga volcano, north of Tanaga Island. The shallow (10 km depth) earthquake occurred at 05:53 UTC January 23 and followed a series of smaller magnitude 2-3 earthquakes in the same region earlier in the day. There is no clear evidence at this time that the M6.2 earthquake or earlier earthquakes are volcanic in nature, nor is there any indication that this seismic activity has any direct implications for future eruptive activity at Takawangha or Tanaga volcanoes. Numerous aftershocks have been recorded, and more are anticipated for a shallow earthquake of this magnitude. AVO will continue to closely monitor the seismic data from Tanaga Island for signs of volcanic unrest.

More information about the M6.2 earthquake can be found from the NEIC here: https://earthquake.usgs.gov/earthquakes/eventpage/us60007djn/executive
and from the Alaska Earthquake Center here: http://earthquake.alaska.edu/event/020124nifl

Takawangha is a remote, 1,449 m (4,754 ft)-high stratovolcano located on the northern portion of Tanaga Island, roughly 95 km (59 miles) west of Adak in the Andreanof Islands. Takawangha's summit is mostly ice-covered, except for four young craters that have erupted ash and lava flows in the last few thousand years. Parts of Takawangha's edifice are hydrothermally altered and may be unstable, possibly leading to localized debris avalanches from its flanks. Takawangha lies across a saddle from historically active Tanaga volcano to the west. No historical eruptions are known from Takawangha; however, field work shows that recent eruptions have occurred and it is possible that historic eruptions attributed to Tanaga may instead have come from Takawangha.


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

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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.