Reservoir Characteristics of Cores from the Antrim Shale, Michigan Basin

Harrison, William¹, Wayne Goodman^2
1 Western Michigan University, Kalamazoo, MI
² Northern Lights Energy, Gaylord, MI

The Upper Devonian Antrim Shale is a major gas producer in the Michigan Basin. Numerous cores in the collection of the Michigan Basin Core Research Laboratory at Western Michigan University have been studied for facies distribution, organic content and fracture characteristics. The Antrim Shale is a classic black shale that produces natural gas by desorption processes into a complex network of fractures. The distribution of high total organic carbon and natural fractures are keys to good productivity. Cores show vertical and lateral facies variation through the basin and the distribution of natural fractures. Gas in place can be measured by geochemical rock analyses and suggest ).5 to 1.0 BCF per 40 acres in the northern part of the basin. Variable production history of project areas can be explained by reservoir rock properties measurable from core, logs and drill cuttings.