Analysis of the Bagley Otsego Antrim Shale Infill Program for 2004: A Case History

Timothy Jay Brock
NuEnergy Operating, Inc, Mason, MI

The Bagley Otsego Antrim Shale Project in Otsego County, Michigan is one of the oldest producing Antrim Shale projects and contains the first wells ever completed in the Antrim Shale, starting in the 1940's. It is rather unique in that the project is not unitized and each well is individually metered. The 2004 infill program was designed to look for areas in which production and ultimate recovery could be enhanced through the drilling of additional wells. In order to perform this analysis, maps of current production rate, cumulative production and percent CO₂ in the gas were prepared. Drilling locations were selected to determine whether the target for additional drilling should be areas of historically low recovery, areas of poor productivity, areas with low CO₂ content in the gas, and whether more modern completion techniques would impact the results. Four wells were drilled and the results of those wells were analyzed. The result was that 3 of the 4 wells were successful, and additional wells have since been drilled and permitted, using the results of this study and the results of the initial 4 wells.