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Geotechnical Engineering


Geophysical Technologies for Detecting Underground Coal Mine Voids:
An Interactive Forum

Locating and Characterizing Abandoned Mines using Microgravity

Presenter: Richard C. Benson, President
Firm/Organization: Technos, Incorporated
Phone: 305-718-9594
Fax: 305-718-9621
Mailing Address: 10430 NW 31 Terrace
Miami, Florida 33172


Surface geophysical methods can be an important part of any site characterization effort. Microgravity is a geophysical method that is increasingly being used for environmental and geotechnical investigations. Microgravity measurements respond to changes in subsurface density, and are a non-invasive way to effectively identify and characterize subsurface voids, including abandoned mines. When integrated with other geologic information and geophysical datasets, a microgravity survey will provide a more complete and accurate assessment of subsurface voids than borings alone. We demonstrate in a case history how microgravity measurements were an effective first step in characterizing a collapse zone in an abandoned mine.

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Updated: 04/15/2015

United States Department of Transportation - Federal Highway Administration