Subject:Abert Rim,a 2,500-foot fault scarp, is one of the highest in the United States.
Captain John C. Fremont named this fault scarp in honor of Colonel J.J. Abert., when his expedition stopped here on December 20, 1843
Abert Rim, some 2,500 feet above the valley floor is one of the highest fault scarps in the United States. This basalt formation, a basic lava covering much of Eastern Oregon, issued from great fissures during the Miocene Period of geologic history many millions of years ago. After this extensive lava flooding, the earth’s crust was fractured at many points and great blocks were tilled. Abert Rim is the western edge of one of these tilted blocks while Abert Lake lies on top of another.