The Little Susitna district, as defined in this report, occupies an area roughly 25 miles long and 3 miles wide on the north side of the lower (western) extremity of the Matanuska Valley in south-central Alaska (fig. 1). The district is bounded on the north by the Talkeetna Mountains, on the south and east by the Little Susitna River, and on the west by the broad lowland of the Susitna River. (See pl. 1.)
This report is based on field work done in the summer of 1952, in which the writer was assisted by Alfred Oestreich, Lewis Ladwig, and Richard Pack. Prior to the present investigation very little was known geologically of the district, except that it was largely covered with alluvial and glacial deposits and that coal-bearing rocks were exposed at three widely separated localities. The purpose of the investigation was to determine, if possible from scattered outcrops and shallow test pits, whether any parts of the district offered sufficient promise of containing minable coal deposits to warrant a more detailed investigation using sub-surface methods.
As a result of this preliminary investigation, plans are being made to explore more thoroughly, by trenching and drilling, some of the more promising parts of the district.
