A recent gas discovery in the Rome Trough has resulted in a new phase of deep exploration in eastern Kentucky. This activity is located in Elliott County, near the northern boundary fault of the Cambrian Rome Trough graben. The Carson Associates No. 1 Kazee well was drilled in 1994, and blew out with a reported uncontrolled flow of 11 million cubic feet of gas per day. Although completed at a much lower rate, this well renewed interest in the deep gas potential of the Rome Trough, which has seen sporadic drilling activity since the 1940's. Gas production in the Rome Trough is from marine sandstones and fractured shales assigned to the Cambrian Rome Formation or Conasauga Group. These units are significantly thicker in the fault-bounded extensional graben that trends west-southwest to northeast in eastern Kentucky and continues through West Virginia and Pennsylvania into New York. Recent mapping of the Precambrian basement surface has refined the structure of eastern Kentucky and the Rome Trough. Reservoir fades include fine- to very fine-grained, micaceous, and glauconitic sandstones and fractured shales. Coarser sandstones may occur near border faults, in fan-delta deposits. Traps are primarily structural, and faulting was contemporaneous with deposition. Stratigraphic traps may also exist in the trough, but have not been proven by drilling to date. Stratigraphic traps may include sandstones deposited in turbidite fans in deeper parts of the graben. Potential hydrocarbon source rocks have not been identified. Limited geochemical analyses of well and outcrop samples from the Rome and Conasauga intervals show poor hydrocarbon source potential. Composition of gas produced from the Rome Trough varies significantly in eastern Kentucky. Several occurrences of gas high in nitrogen and helium content were found in the western part of the trough, and may be related to proximity to the Grenville Front. Gas of commercial quality is typical in the eastern part of the trough, where several wells are producing gas with Btu values over 1,000. Significant hydrocarbon potential remains in the Rome Trough, but this play is characterized by complex faulting that influenced the deposition and distribution of potential reservoir rocks. Interpretation of high-quality seismic data will be a key factor to future success in this play.
Information Circular 54
Digital Object Identifier (DOI)
A portion of this work was completed in preparation of a chapter on the pre-Knox play for "The Atlas of Major Appalachian Basin Gas Plays," funded by the U.S. Department of Energy, Morgantown Energy Technology Center, under contract number DE-FC21-91MC28176. This project also funded part of the preparation of "Preliminary Map of the Structure of the Precambrian Surface in eastern Kentucky" (Kentucky Geological Survey, Map and Chart Series 8, 1995).
Harris, David C. and Drahovzal, James A., "Cambrian Hydrocarbon Potential Indicated in Kentucky's Rome Trough" (1996). Kentucky Geological Survey Information Circular. 58.