Middle and Late Devonian New Albany Shale in the Kentucky Geological Survey Marvin Blan No. 1 Well, Hancock County, Kentucky

A 30-ft section of core was recovered in the Grassy Creek Member of the New Albany Shale in the Kentucky Geological Survey Marvin Blan No. 1 well, Hancock County, Ky. (permit 104925, API No. 16091013960000). Analysis characterized the New Albany Shale as a regional seal for preventing vertical migration of carbon dioxide stored in deeper zones, as a natural gas reservoir, and for its potential for enhanced gas recovery and sequestration of carbon dioxide. A show of natural gas at the top of the New Albany Shale was encountered during drilling. Core was recovered in an aluminum sleeve cut into 3-ft sections. The sleeved sections were capped, sealed, and shipped to Weatherford Laboratories for analysis. An X-ray computed tomography scan of the core, a standard openhole nuclear log suite, and spectral gamma-ray data formed the basis for establishing a sampling and analysis protocol. Three 1-ft intervals were selected for archiving and were sealed in wax. The remaining core was slabbed. The quarter-section slabs were reserved for examination and archiving. The three-quarter-section slabs were photographed and sampled. The New Albany Shale in the Blan well averages 9.5 × 10–5 md permeability with a compressive strength of 13,487 psi, a static Young’s modulus of 1.58 x 106 psi, and a static Poisson’s ratio of 0.20. These properties demonstrate that the shale is an adequate seal for deeper reservoirs. Although thermal maturity is low, the shale is oil-prone, with excellent marine kerogen and bitumen contents. The methane gas content is 55.9 standard cubic feet of gas per ton of shale. This low gas content, when considered in light of low permeability, indicates the New Albany has low potential for thermogenic gas production in the area of the Blan well. Economic gas recovery would likely require horizontal drilling and advanced well-completion technologies. Adsorption isotherms indicate an estimated carbon dioxide gas content of 137.7 scf/ton at an estimated reservoir pressure of 812 psi, indicating preferential adsorption. In addition, as much as 181 tons of carbon dioxide could be sequestered per acre in the New Albany Shale (over its total thickness), suggesting a possible mechanism for enhanced natural gas recovery