STRUCTURAL EVOLUTION OF THE EOCENE SOUTH FORK DETACHMENT, PARK COUNTY, WYOMING

摘要

INTRODUCTION The South Fork Detachment (SFD) is named for its exposure along the banks of the South Fork of the Shoshone River in Park County, Wyoming. The fault trace is exposed along strike for at least 35 km in this valley to the southwest of Cody, WY. The full extent of the fault is unknown due to its concealment by younger units. At its southern limit the fault strikes approximately N50°E before disappearing beneath Eocene Absaroka volcanics. The fault has been interpreted to bend at 90° near Buffalo Bill Reservoir and is lost to the northwest under these same volcanics (Beutner and Hauge, 2009).