ABSTRACT

A full-bore core was taken in September 1994 from the Mead Corporation #3 well located in Perry Township of Hocking County, Ohio. The core was obtained by Murphy Oil Company in cooperation with Columbia Natural Resources, The Clinton Oil Company, and Omega Resources. Core recovery was 76 feet and encompassed the main body of the Rose Run sandstone as it exists in this area of Ohio. A total of 62 plugs were taken from the core and analyzed for porosity, horizontal permeability, and fluid/gas saturations. Additional plugs were taken to test vertical permeabilities. A total of twenty thin section slides were generated from selected intervals. A geologic description, and depositional environment interpretation, of the core indicates that this region of Hocking County Ohio was a shallow siliciclastic carbonate platform during time of deposition of the Rose Run sandstone. Rapid early Ordovician transgression resulted in deposition of the Rose Run sandstone on the erosional surface of the underlying upper Cambrian Copper Ridge Dolomite. Depositional slope is estimated at one foot per mile. The onlapping barrier- backbarrier complex of the Rose Run sandstone is equivalent to the basal transgressive member of the overlying Beekmantown Dolomite. An upland sabkha environment was bordered by an intertidal zone. A broad sand shoal more than ten miles wide existed a short distance offshore. Seaward from the sand shoal was an area of deeper water, sand-flat deposition. Farther offshore, dolomite deposition progressed with the development of a large, barrier type algal reef. Tidal range was in excess of four feet.