By virtue of the Geothermal Steam Act of 1970, the U.S. Geological Survey is required to appraise geothermal resources of the United States prior to competitive lease sales. This appraisal involves coordinated input from a variety of disciplines, starting with reconnaissance geology and geophysics. This paper describes how the results of several geophysical methods used in KGRA evaluation were interpreted by the authors, two geophysicists, involved with both the Evaluation Committee and the research program responsible for obtaining and interpreting the geophysical data to be used by the committee. ?? 1979.