This is an interim report on the findings of a mineral resource study in the Eastern Brooks Range, Alaska, involving 4,300,000 acres of lands. The study area is divided into five geologic terrains and limited field work was undertaken during the 1976-78 field seasons. A sample survey was undertaken throughout the major portion of the project area to more adequately define regions of mineral potential and 1,109 stream sediments and 85 rock samples were analyzed. Select anomalies and prospects were field checked. Further multielement analyses of these samples are being made by the U.S. Department of Energy and will be reported separately by that agency.