Skip to main content
U.S. flag

An official website of the United States government

Return to search results
💡 Advanced Search Tip

Search by organization or tag to find related datasets

Airborne electromagnetic and magnetic survey results from the Upper San Pedro Basin, Arizona, 1997 and 1999

Published by U.S. Geological Survey | Department of the Interior | Metadata Last Checked: September 07, 2025 | Last Modified: 20250905
Airborne electromagnetic (EM) and magnetic survey data were collected by GeoTerrex Ltd. in the Upper San Pedro Basin and Fort Huachuca, Arizona in 1997 and 1999. EM data were collected using a time-domain GEOTEM system towed behind a fixed-wing aircraft with 30Hz cycle rate, 696,000 Am2 dipole moment, and 4 ms pulse width. Magnetic data were collected using a CS-2 cesium vapor magnetometer. Approximately 2,250 line-km were flown. Nominal line spacing was 400–800 m and nominal system height above land surface was 125 m for the electromagnetic sensor and 75 m for the magnetic sensor. Numerical inversions to recover layered resistivity structure were prepared by Condor Consulting, Inc. using the AIRSTEM proprietary inversion code. Average depth of investigation was 400 m. Raw data and AIRSTEM inversions done by Condor Consulting, Inc. are provided in a Geosoft database (Seequent, Inc.). Inverted data are also provided in an XYZ Ascii format. Multiplots showing the AIRSTEM inversion along each transect are provided as PDFs. Original contractor data packages contain raw electromagnetic and magnetic data, positional information, and system information in the original delivered formats (UpperSanPedroAEM_Huachuca_ContractorDataPackage_GeoTerrexLtd_1997.zip and UpperSanPedroAEM_SierraVista_ContractorDataPackage_GeoTerrexLtd_1999.zip). These packages are described in contractor-provided readme.txt files.

Complete Metadata

data.gov

An official website of the GSA's Technology Transformation Services

Looking for U.S. government information and services?
Visit USA.gov