The Knox Exploration Play in Ohio: An Overview

Wicks, John L.
J. L. Wicks Exploration, Wooster, OH

The Knox Dolomite (Cambro-Ordovician) in Ohio consists of a mixed carbonate and clastic sequence up to 1400 feet thick. The top of the Knox is a regional unconformity where oil and gas are trapped predominantly in erosional remnants, productive from thin sandstones and vuggy dolomites. The Knox producing trend extends 200 miles in eastern Ohio from Ashtabula to Ross County.

Interest in Knox exploration began in 1961 after successful wells in Morrow County flowed oil in excess of 2000 barrels per day from the Copper Ridge dolomite. Over one thousand completions there combined to produce nearly 45 million barrels of oil prior to 1973. Interest in the Knox resumed in 1980 with the discovery of the Bakersville Field in Coshocton County where wells produced gas from the Beekmantown at over 1,000,000 cubic feet per day. Since then, 1300 completions in 23 counties have produced over 44 million barrels of oil equivalent (BOE) from Knox oil and gas pools.

Fifty oil and gas fields are recognized within the Knox trend in Ohio. Outside of Morrow County, eighty-five percent of all Knox reserves have been recovered from 90 pools containing 500 wells. Five notable pools including East Randolph, Overton, South Canaan, Birmingham-Erie and Muskie have produced over 10 million BOE.

Plots of drilling activity, Cumulative Production versus Number of Wells drilled and Reserves versus Year Discovered indicate that the Knox is a mature and waning exploration play. This is reflected in the lack of current drilling activity in the face of near record product prices.

AAPG Search and Discovery Article #90031©2004 AAPG Eastern Section Meeting, Columbus, Ohio, October 3-5, 2004