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Ground-Based Time-Domain Electromagnetic Data Collected at Edwards Air Force Research Laboratory, Antelope Valley, California, 2018

Metadata Updated: October 29, 2023

Time-domain electromagnetic (TEM) surveys were done northwest of the Air Force Research Laboratory (AFRL) at Edwards Air Force Base. TEM surveys were done at 33 locations between May and October 2018 to refine the understanding of the bedrock-alluvial aquifer transition zone downgradient from the AFRL. TEM surveys (also called transient electromagnetic surveys) provide 1D resistivity soundings of the subsurface, which can be related to lithology and hydrogeology. In the TEM method, electrical current is cycled through a transmitter loop (Tx) wire, which in turn produces a primary magnetic field. When the current is abruptly terminated, a secondary magnetic field is induced in the earth, and it moves downward and outward as the induced current decays with time. The decay is controlled by the resistivity of the earth. A receiver (Rx) at the center of the Tx loop measures the secondary magnetic field as a function of time (dB/dt). Decaying voltage measurements at the receiver are converted to apparent resistivity, which can be inverted to recover the depth-dependent vertical resistivity structure of the earth below the receiver location. Other geophysical techniques, including electrical resistivity tomography and horizontal-to-vertical spectral ratio passive seismic, co-located with the TEM data are made available in other child pages within this data release: This page contains the TEM data, spatial information for the TEM surveys, and preliminary processed TEM data.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Created Date June 1, 2023
Metadata Updated Date October 29, 2023

Metadata Source

Harvested from DOI EDI

Additional Metadata

Resource Type Dataset
Metadata Created Date June 1, 2023
Metadata Updated Date October 29, 2023
Publisher U.S. Geological Survey
Identifier USGS:5c7d93bce4b0fe48cb532d45
Data Last Modified 20200819
Category geospatial
Public Access Level public
Bureau Code 010:12
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id 5ce8ac8b-fc41-4186-a442-86758f465ebf
Harvest Source Id 52bfcc16-6e15-478f-809a-b1bc76f1aeda
Harvest Source Title DOI EDI
Metadata Type geospatial
Old Spatial -117.7398,34.9505,-117.6584,34.9761
Publisher Hierarchy White House > U.S. Department of the Interior > U.S. Geological Survey
Source Datajson Identifier True
Source Hash 3b728c8948cad8c1c194c1cc5df45b7cfaa29f40c3478e35ba4f9ec449a22d3a
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -117.7398, 34.9505, -117.7398, 34.9761, -117.6584, 34.9761, -117.6584, 34.9505, -117.7398, 34.9505}

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