Avak crater

Avak is an impact crater centered approximately 12 km (7.5 mi) southeast of Utqiagvik, Alaska, United States.

The Avak structure has no surface expression in the swampy, lake-dotted tundra of the Arctic coastal plain.

The structure is covered by a thin veneer of permanently frozen Pliocene and Pleistocene rock.

[2] Palynological data on its ejecta suggest Middle–Late Turonian age of the impact (about 90 million years ago).

The Navy drilled the Avak 1 well in 1951–1952 and encountered deformed rocks from near the surface to a total depth of 1,225 m (4,019 ft).