PETROLEUM GEOLOGY OF THE UPPER DEVONIAN GORDON SAND, SOUTHERN WEST VIRGINIA

Gas production from the Upper Devonian Gordon Sand in southern West Virginia is derived from two linear trends. The primary trend is a sand belt approximately 15 miles wide and 100 miles long extending from McDowell to Kanawha counties. The secondary trend is offset about 12 miles to the west of the primary trend and is about 6 miles wide and currently extends about 25 miles long from McDowell to Logan counties. The primary trend is comprised of at least three amalgamated sand sheets each ranging to about 20 feet thick. The secondary trend ranges from a thin porous interval to a series of thin silty beds up to about 5 feet thick. The primary trend is interpreted to be a shoreline sand whereas the secondary trend is interpreted to represent turbidites. Gas production in the primary trend is from the middle sand sheet and has maximum log porosities ranging from 9% to 16%. Log porosity in the secondary trend is about 6-7%. Potential for continued development of these trends is good.