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The Rome trough, a northeast-trending graben, is that part of the Cambrian interior rift system that extends into the central Appalachian foreland basin in eastern North America. On the basis of changes in graben polarity and rock thickness shown from exploration and production wells, seismic lines, and gravity and magnetic intensity maps, we divide the trough into the eastern Kentucky, southern West Virginia, and northern West Virginia segments. In eastern Kentucky, the master synthetic fault zone consists of several major faults on the northwestern side of the trough where the most significant thickness and facies changes occur. In southern West Virginia, however, a single master synthetic fault, called the East-Margin fault, is located on the southeastern side of the trough. Syndepositional motion along that fault controlled the concentrated deposition of both the rift and postrift sequences. The East-Margin fault continues northward into the northern West Virginia segment, apparently with less stratigraphic effect on postrift sequences, and a second major normal fault, the Interior fault, developed in the northern West Virginia segment. These three rift segments are separated by two basement structures interpreted as two accommodation zones extending approximately along the 38th parallel and Burning-Mann lineaments.
Computer-aided interpretation of seismic data and subsurface geologic mapping indicate that the Rome trough experienced several major phases of deformation throughout the Paleozoic. From the Early(?)-Middle Cambrian (pre-Copper Ridge deposition), rapid extension and rifting occurred in association with the opening of the Iapetus-Theic Ocean at the continental margin. The Late Cambrian-Middle Ordovician phase (Copper Ridge to Black River deposition) was dominated by slow differential subsidence, forming a successor sag basin that may have been caused by postrift thermal contraction on the passive continental margin. Faults of the Rome trough were less active from the Late Ordovician-Pennsylvanian (post-Trenton deposition), but low-relief inversion structures began to form as the Appalachian foreland started to develop. These three major phases of deformation are speculated to be responsible for the vertical stacking of different structural styles and depositional sequences that may have affected potential reservoir facies, trapping geometry, and hydrocarbon accumulation.
Dengliang Gao received a B.S. degree (1983) and an M.S. degree (1986) in geology from Hefei University of Technology, People's Republic of China. From 1986 to 1991, he worked as a lecturer at Tongji University, People's Republic of China, where he won the National Science and Technology Progress award for his research project in 1991. In 1992, he went to the United States and received an M.S. degree in geology from West Virginia University (1994) and a Ph.D. in geology from Duke University (1997). After spending one year in the oil industry at Exxon Production Research Company, he joined Marathon as a geologist in 1998, focusing on three-dimensional seismic interpretation and visualization. His current interests include computer-aided structural and stratigraphic interpretation of three-dimensional seismic using attribute and visualization technologies.Robert C. Shumaker received an A.B. degree (1953) from Brown University and an M.S. degree and Ph.D. (1960) in geology from Cornell University. He worked for the Humble Oil and Refining and Exxon Companies in their research and exploration departments from 1960 to 1972. He joined the faculty in the Department of Geology and Geography at West Virginia University in 1972 where he was a professor and where he was associated chairperson of the department from 1984 to 1995. He retired in 1996 and presently is a professor emeritus at West Virginia University.
Thomas H. Wilson received B.A. (1974) and M.S. (1977) degrees in physics, and a Ph.D. (1980) in geology from West Virginia University (WVU). He worked with Exxon Company USA (1981-1983) in the EDPC special seismic problems group and later in the Gulf Atlantic division seismic evaluation group. In 1983, he joined the WVU Department of Geology and Geography, where he is a professor. He teaches courses in applied geophysics and quantitative methods.