Vol. 12 (1988)
Grand Teton Np Report

Structural History of the Buffalo Fork Fault and Ancestral Washakie Range, Wyoming

David R. Lageson
Montana State University

Published 1988-01-01

Abstract

The Buffalo Fork fault is an east-dipping, north-trending reverse\thrust fault which lies along the west side of the Washakie Range in northwestern Wyoming (Love, 1975). This fault was active during the Laramide Orogeny (60-55 million years ago), during which time it uplifted the Ancestral Washakie Range. The purpose of this on-going research project is to determine the displacement vector of the Buffalo Fork fault and to relate this to the regional kinematic pattern of Laramide deformation in northwestern Wyoming. Previous field work by the author (Lageson, 1987) has shown that other Laramide faults in northwestern Wyoming experienced significant components of oblique-slip, depending on their orientation. If a regional pattern of displacement can be determined from several faults, then it may be possible to reconstruct the crustal stress field during the Laramide Orogeny. This study of the Buffalo Fork fault is one step toward this greater goal.