Potential subsurface structures and hydrocarbon reservoirs in the southern Appalachian basin beneath the Cumberland Plateau and eastern Highland Rim, Tennessee, Kentucky, and southwestern Virginia.

摘要

Oil and gas exploration in the southern Appalachian basin is typically concentrated around areas with historically proven reserves and very limited prospecting is conducted elsewhere in the region. To remove possible correlation problems and promote regional prospecting a standardized picking methodology was established in geophysical logs for the Middle Ordovician carbonate lithofacies (Nashville-Stones River Groups). This methodology was then used to correlate the units across Cumberland Plateau of Tennessee, Kentucky, and Virginia, from the Nashville-Jessamine domes to the Clinchport-Whiteoak Mountain thrust in the Valley and Ridge. The same lithofacies may extend in Ohio, Pennsylvania, and New York, suggesting a standardized nomenclature be established. This methodology is key to resolving regional and local structures, and structural trends in this area.; To identify deformation probably associated with blind structural trends and producing fields, regional structure contour, trend surface residual anomaly, and isopach maps were constructed using data from 7,639 geophysical logs, 1,960 drill cores, and 433 surface contacts. These maps correlate well with known producing fields and identified a possible decollement in the Chattanooga Shale along with the southern extension of the Rome trough in Tennessee. A geologic model for hydrocarbon emplacement was constructed to accommodate all the available structural and petroleum information. The model illustrates a proposed decollement soled in the Chattanooga Shale that forms linear potential Mississippian-age traps and a previously unidentified continuation of the Rome trough and Sequatchie Valley fault beneath the western section of the Wartburg basin in Tennessee.; The Flynn Creek impact structure was also investigated because it has a good hydrocarbon potential and may have economical reserves. The impact occurred in a carbonate-dominated target during the Late Devonian. Four persistent, concentric faults indicate the Flynn Creek impact structure is not asymmetric and has a diameter of 4.7 km (2.9 mi), which was calculated from the outermost partially developed fault system, or 4 km (2.5 mi) using the third fault system, which is fully developed. Both estimates are larger than the previously estimated 3.8 km.