CORRELATING DEEP PENNSYLVANIAN STRATA IN THE EASTERN KENTUCKY COAL FIELD FOR POTENTIAL CBM AND CO2 STORAGE

Kentucky has vast coal resources and is the third largest producer of coal in the United States. In eastern Kentucky, production is mostly from Middle Pennsylvanian coal beds and the majority of coal resources are above drainage. Much of the Lower Pennsylvanian section is dominated by thick, quartzose sandstones. In the Eastern Kentucky and Middlesboro Synclines, however, some lower Middle Pennsylvanian and Lower Pennsylvanian coal beds are preserved at depths of more than 1,000 feet below drainage above the thick, quartzose sandstones. Some coal beds also occur between the thick Lower Pennsylvanian sandstones. Currently, there is no CBM production from these coal beds, which are stratigraphically younger than known CBM-producing coals in neighboring southwest Virginia. The Virginia coals are truncated updip by thick, quartzose sandstones in southeastern Kentucky. In order to determine if there is potential for CBM or for enhanced CBM with CO2 storage in the slightly younger coals of eastern Kentucky, detailed stratigraphic sections across the synclines are needed to first determine the number and lateral extent of potential coal-bearing sequences. One problem with attempting to correlate the deeper coal-bearing section in the synclines is that there are no coal exploration boreholes at depth in these areas. Therefore, other data is needed. As part of the SECARB partnership, subsurface oil-and-gas wells are being used to better understand the stratigraphy of the Lower Pennsylvanian and lower Middle Pennsylvanian strata in the synclines. Typically, oil and gas wells case off the Pennsylvanian, so that there are few density logs of the deeper coal-bearing strata. There are however, many gamma and neutron logs that can be used to correlate Lower Pennsylvanian sandstones and typical coarsening-upwards sequences of coal-bearing intervals in the Lower Pennsylvanian Grundy Formation and Middle Pennsylvanian Pikeville Formation. These logs are being used in combination with those few locations with density data to facilitate detailed high-resolution cross sections across the synclines. These sections will help to show areas where there is the potential for Lower Pennsylvanian and lower Middle Pennsylvanian coal beds at depth in southeastern Kentucky.