California Oil, Gas, and Groundwater Program

Publication: Data Releases


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Ball, L.B.


U.S. Geological Survey data release



Airborne electromagnetic (AEM) and magnetic survey data were collected during October 2016 along 1,443 line kilometers in the southwestern San Joaquin Valley near Lost Hills, California. These data were collected in support of groundwater salinity mapping and hydrogeologic framework development as part of the U.S. Geological Survey California Oil, Gas, and Groundwater program and the California State Water Resources Control Board’s Program of Regional Monitoring of Water Quality in Areas of Oil and Gas Production. Data were acquired by SkyTEM ApS with the SkyTEM 312 time-domain helicopter-borne electromagnetic system together with a Geometrics G822A cesium vapor magnetometer. The survey was designed to cover the region hydrogeologically downgradient and within 5 km of the Lost Hills, North Belridge, and South Belridge oil fields. Additional lines were extended to the west, east, and south for hydrogeologic context. The AEM typical maximum depth of investigation is about 300 m. The survey was flown at a nominal flight height of 35 m above terrain along block-style lines with a nominal spacing of 150 to 300 m.

This data release includes minimally processed (raw) AEM and raw/processed magnetic data, fully processed AEM data used for resistivity model development, and laterally constrained inverted resistivity models along all flight lines.