Elk Basin

View of Elk Basin facing north along the axis of the anticline. Note strata dipping to the right and left on the sides of the image.

Elk Basin is a valley on the border of Montana and Wyoming in the United States. It is an active oil field with hundreds of derricks operating in it. Geologically, it is a breached anticline formed by a deep subsurface thrust fault. Most of the rocks at the surface are Cretaceous in age, including the Lance Formation, Meeteetse Formation, Mesaverde Formation, Cody Shale, and Frontier Formation.[1]

  1. ^ Pierce, W.G., 1997, Geologic map of the Cody 1 degree x 2 degrees quadrangle, northwestern Wyoming: U.S. Geological Survey, Miscellaneous Geologic Investigations Map I-2500, scale 1:250000.