Integrated geophysical study of the Triassic Richmond Basin, Virginia


A geophysical study was carried out in the Richmond basin, a Triassic graben in Virginia, as part of a hydrocarbon exploration program. A general 3-D model of the basin was constructed using 2.5-D gravity and magnetic anomaly inversions along a series of traversing profiles and combined with seismic reflection results. Because of the complexity of anomalies of intrabasement sources, some innovative techniques were employed to isolate a possible basin anomaly and then to model the results. Another problem is the very small density and susceptibility contrasts of the basin sediments and the tendency for metamorphics to have velocities and reflectors mat appear sedimentary in origin. Interpretations of subsequent seismic reflection lines agreed with the potential field results and show a half graben down to the west with wide shallow pediments, as well as other basin structures. The results indicate the need for an innovative, integrated approach to studying such Triassic basins.

Document Type

Conference Proceeding



Publication Date


Journal Title

1985 SEG Annual Meeting, SEG 1985