by S.S. Johnson, 48 pages, 2 maps (1 in color), 2 figures, 1973. The area of this gravity report consists of approximately 8,800 square miles in Virginia, extending from 78 degrees west longitude east to the Chesapeake Bay and Potomac River north of 37 degrees, 30 minutes north latitude, and the Eastern Shore Peninsula. The survey included areas in the Valley and Ridge, Blue Ridge, Piedmont and Coastal Plain physiographic provinces. Gravity methods are used predominantly in regional surveys to help determine the location of anomalous areas that may be further investigated by geological and other geophysical techniques. Correlation was found to exist between the gravity anomalies and geological structure.
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