Facies analysis of the Devonian Gordon Stray Sandstone in West Virginia

Since its discovery in 1895, West Virginia's Jacksonburg-Stringtown field has had a primary production of 20 million barrels of oil. Based on 10 full-bore cores from Wetzel and Tyler Counties, the reservoir---the Gordon Stray Sandstone---is interpreted to be part of a barrier-island complex, comprising (from bottom to top) lower-shoreface, upper-shoreface, and foreshore sandstone. Tying core interpretations to 123 well logs across the field enables the various facies to be mapped. The major pay zone occurs stratigraphically within the middle of the shoreface facies, a medium-grained, well sorted sandstone. The barrier-island then prograded rapidly westward, laying down a thin sandstone. Mapping of these back-barrier facies identifies two washover lobes in the western part of the field, spilling eastward into the lagoon. This map pattern strongly suggests that another thick barrier-island complex exists at some close distance to the west of the Jacksonburg-Stringtown field, a previously unknown exploration target in the Upper Devonian Gordon Stray Sandstone.