Report describing a high-sensitivity aerial gamma-ray spectrometer and magnetometer survey conducted in the lower Yukon River and Kuskokwim River areas of southwestern Alaska (covering fifteen quadrangles) and in the middle Yukon River valley in Interior Alaska (covering eight quadrangles) as part of the National Uranium Resource Evaluation (NURE) Program of the United States Energy Research and Development Administration (ERDA). This program provides information on reconnaissance radioelement distribution to assist in assessing the uraniferous material potential in the United States. The analysis includes medium values of eU, eTh, and K (equivalent uranium, thorium, and potassium) contents of geological units.

From addendum: Two types of analyses for uranium in the stream-sediment samples are presented. One split of the stream-sediment samples was sent to Resource Associates of Alaska's laboratory, where they were analyzed for U by the fluormetric method after acid extraction. This is the method employed for U by most laboratories. The completeness of uranium extraction unavoidably varies with the particular type of uranium-bearing minerals present and possibly with the amount of iron, manganese, and carbonaceous material present, which can interfere with the extraction. Analyses by the method are shown in the text and appendix columns with the designation "RAA."

Appendix computer data listings to accompany a report on aerial radiometric and magnetic survey of the Bethel and Yukon areas in Alaska. Single-record and averaged-record data listings are prepared for each NTMS quadrangle surveyed. Within each quadrangle, the data are arranged by flight line and contain, as heading information on each page, the contractor's name (Texas Instruments), the name of the survey, the name of the NTMS quadrangle, the flight-line number, and the day of year on which the data were collected.