Hydrocarbon Depletion of Clinton Wells in Mahoning County, OH

Jeffrey L. Seibert

The Scattergood 1A and Luplow Unit 1 wells were in-field drilled on 60-70 acre spacing among wells that had been producing for 10 years. An ultimate-recovery gas-production map indicates these two wells should each produce between 200 and 250 mmcf throughout their productive lifetime. Projected decline curves for the two wells from their first 2 years of production indicate they will produce between 75 and 100 mmcf during the first 10 years of their productive lives, well below the 228 mmcf ultimate gas recovery average for the surrounding producing wells.

No dominating factors apparently influence production of these two in-field wells that would not affect production of surrounding wells. The in-field wells lie within the thickest section of an east-west-trending sandstone body and contain less porosity over 6% than some of the surrounding wells. Some surrounding wells possess a relatively thin accumulation of porosity greater than 6% and still produce over 200 mmcf. The in-field wells lie at the edge of, or within, a structural terrace at similar structural position as surrounding wells that will produce over 200 mmcf. Neither of the in-field wells produce paraffinic oil that might affect gas production. Despite these factors, production from the in-field drilled wells ranks among the lowest 10% of the 129-wells. The average producti n of the surrounding wells ranks among the top 20%. Low production of the in-field drilled wells may be the result of efficient draining by surrounding wells on 60-70-ac spacing.

AAPG Search and Discovery Article #91041©1987 AAPG Eastern Section Meeting, Columbus, Ohio, October 7-10, 1987.