This report gives the results of geologic investigations in the Yakataga district on the south coast of Alaska, including detailed geologic mapping in the southeastern part of the Robinson Mountains, and reconnaissance study of the stratigraphy and structure of adjoining areas. The geologic map that accompanies this report covers an area of 630 square miles and includes the Bering Glacier (A-2), (A-3), and (A-4) quadrangles and the Icy Bay (D-2 and D-3) quadrangle of the Alaska inch-to-the-mile quadrangle map series. (see fig,. 1.)