Petroleum Geology of Whirlpool Member (Silurian) of McConnelsville Field, Morgan County, Ohio: ABSTRACT

Abstract

With the drilling of the 1 Forrest Knox, Meigsville Township, Morgan County, Ohio, by O'Neal Productions, Inc., in July 1977, a new pay in the McConnelsville field was opened when production was obtained from the Whirlpool Member of the basal Silurian Albion Group. More than 20 wells have been drilled in this pool and sufficient production has been obtained to extrapolate production curves. These curve extensions indicate that an average well should produce 58,000 bbl of oil on 40-acre spacing over a 10-year life. This is believed to be a more accurate representation of expectations than the 9,000 bbl indicated by volumetric calculations, or the 120,000 bbl indicated by a previous paper on the Blue Rock field in Muskingum County, Ohio. The Whirlpool Member is a very fine to medium-grained, white to light-gray sandstone that was deposited in meandering channels on a broad delta plain of the Ordovician Queenston Formation. Three deposition zones are present in the Whirlpool, with varying oil and water saturations in each zone. Production is directly related to log porosities indicated by correlation of compensated density readings. Such porosity trends are difficult to project. Drilling has been restricted to the rotary method with air rotaries encountering fewer difficulties than mud rotaries. Completion techniques have been confined to fracture treatments using a relatively slow injection rate and appear to be quite successful in confining the treatment to the formation. The relation of this pool to the older Blue Rock pool and to the scattered few test wells indicates that a substantial area of untested Whirlpool awaits exploration and should reward the explorer. End_of_Article - Last_Page 845------------