Recognition on Wireline Logs and Mapping of Oolitic Facies in a Carbonate Sequence, Ste. Genevieve Limestone, Illinois Basin

Abstract

Oolitic facies of the Ste. Genevieve Limestone are common and prolific hydrocarbon reservoirs in the Illinois basin. However, development and exploration efforts are often hampered by the inability to recognize the reservoir on wireline logs. A comparison of cores with wireline logs in northern Lawrence field, Lawrence County, Illinois, indicates that a subjective but predictable relationship exists between carbonate lithology and log character. Mapping of the oolitic facies to determine orientation, geometry, and extent can be accomplished in areas where wireline logs are the only data available.