The Lower Silurian Clinton Sandstone is the most commonly drilled formation in eastern Ohio. Successful exploration for subtle stratigraphic traps requires detailed knowledge of Clinton depositional systems. Two highly constructive cratonic delta systems (Claysville and Salt Fork deltas) are present in Guernsey County, Ohio. These deltas are typical of the small deltaic complexes present along the eastern margin of the Clinton-Medina production trend. Production from these deltaic deposits occurs in multistory and laterally discontinuous sandstone bodies deposited as distributary mouth bars, distributary channel fill, and delta-plain point bars. Criteria used to define depositional environments and patterns include: (1) sandstone isopach maps, (2) gamma-ray log cross sect ons, (3) log signature, and (4) slice isopach maps. Environmental interpretations are augmented by examination of two cores and thin sections. The three types of sandstone deposits are interrelated in a predictable manner and each has a unique isopach pattern, log signature, and production characteristics. Distributary mouth bar deposits are the most common reservoirs, and are characterized by coarsening-upward log signatures and elongate isopach patterns. Distributary channel-fill deposits are the most prolific reservoirs, and have eroded into underlying mouth-bar deposits. They are characterized by blocky log signatures and linear, narrow isopach patterns. Meander point-bar deposits have fining-upward log signatures and an ovoid to kidney-shaped isopach pattern. These methods and resul s provide a visualization of paleogeography and sedimentologic processes that should be used as a guide for development of and exploration for the Clinton Sandstone.

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