High-Resolution Aeromagnetic Survey of the Greater Spokane Area, Washington and Idaho

This data release provides access to a low-altitude, aeromagnetic survey of a part of eastern Washington and northwestern Idaho centered approximately at Spokane, Washington, and referred to as the Spokane aeromagnetic survey. The survey includes the cities of Spokane and Cheney, numerous smaller communities, and Fairchild Air Force Base. Magnetic anomalies reflect Miocene rocks of the Columbia River Basalt Group overlying Precambrian through Mesozoic basement rocks, including the Priest River metamorphic core complex. These data were acquired between May 17 and June 12, 2013, by EDCON-PRJ, Inc., working under contract to the U.S. Geological Survey. Total magnetic field values were acquired using a fixed-wing aircraft flown at a target elevation 200 m above terrain (300 m over Spokane) and along flight lines and tie lines spaced 400 m and 4000 m apart, respectively. Flight lines were directed with a heading of 70 degrees east of north; tie lines were directed 160 degrees east of north. A total of 12,105 line-kilometers were acquired over an area of 4,330 square km. The details of the Spokane aeromagnetic survey are described in the document Spokane_Contract_Report.pdf available for download in this data release.