Ukinrek Maars
Ukinrek Maars | |
---|---|
Highest point | |
Elevation | 299 ft (91 m) |
Coordinates | 57°49′54″N 156°30′35″W / 57.83167°N 156.50972°W[1] |
Geography | |
Location | Becharof National Wildlife Refuge, Alaska, on Alaska Peninsula |
Parent range | Aleutian Range |
Geology | |
Mountain type | Maars |
Last eruption | March to April 1977 |
The Ukinrek Maars are two phreatomagmatic vents that formed on the north side of the Aleutian Range on a low area bordering the Bering Sea. The maars are 1.5 km south of Becharof Lake and 12 km northwest of Peulik Volcano. The western of the two is elliptical in shape and up to 170 m in diameter and 35 m deep. The east maar lies 600 m to the east and is circular and up to 300 m in diameter and 70 m deep. The east maar has a 49 m-high lava dome within the crater lake.[2]
The eruption occurred in March and April 1977 and lasted for ten days. There was no previous eruption. The magmatic material was olivine basalt from a mantle source. Pyroclastic surge from the eruptions traveled to the northwest.[1] The volume of lava erupted was 9×105 m3 and the volume of tephra expelled was 2.6×107 m3.[3]
The Quaternary age Gas Rocks dacite domes some three km to the northeast were the site of a phreatic eruption some 2300 years ago.[1]
References[]
- ^ a b c "Ukinrek Maars". Global Volcanism Program. Smithsonian Institution. Retrieved 2021-06-28.
- ^ Miller, T.P., et. al., 1998, Catalog of the historically active volcanoes of Alaska: U.S. Geological Survey Open-File Report 98-0582, 104 p
- ^ "Ukinrek Maars: Eruptive History". Global Volcanism Program. Smithsonian Institution. Retrieved 2021-06-28.
External links[]
- Volcanoes of the Alaska Peninsula and Aleutian Islands-Selected Photographs
- Alaska Volcano Observatory
Wikimedia Commons has media related to Ukinrek Maars. |
- March 1977 events in the United States
- April 1977 events in the United States
- Active volcanoes
- Maars of Alaska
- Volcanic crater lakes
- Landforms of Lake and Peninsula Borough, Alaska
- Aleutian Range
- Lake and Peninsula Borough, Alaska geography stubs