ABSTRACT: Gas Production from the New Albany Shale

HAMILTON-SMITH, TERENCE, Kentucky GeologicaI Survey, Lexington, KY

Gas production from the New Albany Shale has been established in over 50 fields in the Illinois basin, 35 of which are in western Kentucky. Vitrinite reflectance data suggest that the thermal maturity of the shale is predominantly in the "oil window," an interpretation supported by the identification of the New Albany Shale as the predominant source rock for produced oil in the Illinois basin. Analyses indicate

that the composition of gas produced from the shale is highly variable, and may include substantial amounts of heavier gases and light oils in addition to methane. Small amounts of oil have also been produced from the New Albany Shale in 14 fields in western Kentucky. Compositional fractionation in the reservoir can explain production of residual gas from the shale matrix, originally generated in association with more abundant oil.

The Shrewsbury Consolidated field in Grayson, Edmonson, and Butler Counties of western Kentucky has 86 wells that have produced gas from the New Albany Shale, at an average initial open flow per well of 170 MCFPD. Examination of geophysical logs from field wells will show that gas entry into the borehole is localized at discrete fracture zones in the shale reservoir.

Second-order derivative maps of field structure will be interpreted to suggest significant faulting at the reservoir level. Temperature logs from as many as 51 field wells will be analyzed to establish a relationship between the magnitude of the temperature anomaly and the initial open-flow rate.

AAPG Search and Discovery Article #91013©1992 AAPG Eastern Section Meeting, Champaign, Illinois, September 20-22, 1992 (2009)