Great Sitkin Volcano
Updated: Apr 27, 2024 11:59 GMT -
Stratovolcano 1740+ m / 5,709 ft
United States, Aleutian Islands, 52.08°N / -176.13°W
Current status: minor activity or eruption warning (3 out of 5)
United States, Aleutian Islands, 52.08°N / -176.13°W
Current status: minor activity or eruption warning (3 out of 5)
Last update: 24 Apr 2024 (Smithsonian / USGS Weekly Volcanic Activity Report)
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Great Sitkin volcano eruptions: 2021, 1974
Latest nearby earthquakes
| Time | Mag. / Depth | Distance / Location | |||
| Apr 17, 07:45 am (Adak) | 0.6 1.8 km | 4.3 km (2.7 mi) to the SW |  23 mi northeast of Adak, Aleutians West, Alaska, United States | Info | |
| Sunday, April 14, 2024 GMT (3 quakes) | |||||
| Apr 14, 04:38 am (Adak) | 1.6 9.6 km | 9.8 km (6.1 mi) to the N | 44 km NE of Adak, Alaska | Info | |
| Apr 14, 01:45 am (Adak) | 0.4 1.8 km | 1.6 km (1 mi) to the SW | 39 km ENE of Adak, Alaska | Info | |
| Apr 13, 06:12 pm (Adak) | 0.2 1.8 km | 1 km (0.6 mi) to the N | 41 km NE of Adak, Alaska | Info | |
Background
Constructed within the caldera of an older shield volcano forming the northern half of Great Sitkin Island, 1740-m-high Great Sitkin volcano contains a small, 0.8 x 1.2 km ice-filled summit caldera. Deep glacial valleys radiate from the summit, which lies at the eastern rim of the caldera, which was formed by massive edifice failure that produced a submarine debris avalanche that traveled more than 40 km to the north. The entire island is blanketed with a light-brown to black pumice layer up to 6 m thick. This deposit is overlain over much of the NW side of the island by ash deposits from a subsidiary vent NW of the caldera. Hot springs, mud pots, and fumaroles occur near the head of Big Fox Creek, south of the volcano. Historical eruptions have been recorded since the late-19th century. In 1945, a 400-600 m wide, flat-topped lava dome was emplaced through a glacier filling the steep-sided, 180-m-deep summit caldera.---
Smithsonian / GVP volcano information
Latest satellite images
