NURE aerial gamma-ray and magnetic reconnaissance survey: NE Washington area, Okanogan NM 11-10, Sandpoint NM 11-11 Quadrangles. Volume I. Narrative report

Abstract

As part of the Department of Energy (DOE) National Uranium Resource Evaluation (NURE) Program, LKB Resources, Inc. has performed a rotary-wing, reconnaissance high sensitivity radiometric and magnetic survey in north-east Washington. Three 1:250,000 scale NTMS quadrangles (Spokane, Sandpoint, and Okanogan) were surveyed. A total of 14,421 line miles (23,203 kilometers) of data were collected utilizing a Sikorsky S58T helicopter. Traverse lines were flown in an east-west direction at 1.0 and 3.0 mile (1.6 and 4.8 kilometers) spacing, with tie lines flown in a north-south direction at 12 mile (20 kilometer) spacing. The data were digitally recorded at 1.0 second intervals. The NaI terrestrial detectors used in this survey had a total volume of 2,154 cubic inches. The magnetometer employed was a modified ASQ-10 fluxgate system. This report covers only the Okanogan and Sandpoint 1:250,000 scale NTMS quadrangles. Spokane 1:250,000 scale NTMS quadrangle is covered in a separate report. The radiometric data were normalized to 400 feet terrain clearance. The data are presented in the form of computer listings on microfiche and as stacked profile plots. Profile plots are contained in Volume II of this report. A geologic interpretation of the radiometric and magnetic data is included as part of this report.