From introduction: This report contains information concerning the geology of Big Horn County and the Crow Indian Reservation and their resources in ground water, coal, oil, and gas. These facts were collected in the course of studies for about a dozen field projects, which ranged in character from reconnaissance studies of large areas to very detailed mapping of certain tracts to show the occurrence of oil and gas. Consequently, the information at hand, either as to the geology or the resources, is not equally complete and definite for all parts.

From introduction: The district described in this report is a triangular area covering about 300 square miles in the southwestern part of the Talkeetna Mountains. The Kashwitna River forms the northern boundary, the Susitna Valley flats the western, and the Willow Creek gold district, which is in the extreme southwestern part of the Talkeetna Mountains, the southern. As the area examined is not a distinct geographic unit, its boundaries being arbitrarily chosen and set only by the limitation of time spent in the field, a description of its geography applies to practically the entire western and southern portions of the Talkeetna Mountains, of which it is a part.