A simple Bouguer gravity map and a total magnetic intensity map were made for the Eastern Shore area of Virginia. Both maps exhibit a great similarity, thus suggesting that the density contrast between the crystalline basement and the overlying sediments is the main source of the gravity anomalies. The maps show two major anomaly trends, north, and N. 30° W. The northwest end of a trough that trends N. 30° W. appears to occupy the northern half of the area and extends southeastward toward the Atlantic Ocean. It also appears to be separated from the adjacent Salisbury embayment, on the subaerial coastal plain, by a large basement uplift centered over the town of Girdletree, Maryland.

Quantitative interpretations of the gravity map were made along three profiles. The thicknesses of the sedimentary rocks in the vicinity of the town of Cheriton, between the towns of Exmore and Melfa, and near Wallops Island are estimated to be 7,200; 2,200; and 6,300 ft (2,195; 670; and 1,920 m), respectively. A fault trending N. 30° W. through Exmore is also suggested; if present, its structural throw would be about 1,300 ft (400 m).

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