Preliminary geologic mapping of the Little Susitna district in 1952 showed that an area of at least 140 square miles is underlain by coal-bearing rocks of Tertiary age, and indicated that coal beds of minable quality and thickness might be present at several localities. Detailed exploration with a bulldozer and power auger was done at these localities in 1953 and 1954 with special attention to strip-mining possibilities.
All the beds examined at the four localities tested were judged to be either too thin or too dirty to be minable under present conditions, and none of them are favorably situated for strip mining.