ABSTRACT: Paleotectonic Controls on Sandstone Trends and Depositional Facies Distribution of the Low-Permeability, Gas-Bearing Cleveland Formation (Upper Pennsylvanian), Texas Panhandle

HENTZ, TUCKER F., Bureau of Economic Geology, University of Texas at Austin, Austin, TX

Low-permeability ("tight") reservoir sandstones of the Cleveland Formation have produced over 412 bcf of natural gas through January 1990, mostly from Ochiltree and Lipscomb counties in the northeastern Texas panhandle. Although large-scale gas production started in 1956, the regional stratigraphic, depositional, and structural settings of the Cleveland are poorly known. A study was conducted in a 5100-sq mi, seven-county area in the western Anadarko basin using log suites from over 860 evenly spaced wells, three cores, and numerous sample logs. The Cleveland Formation is well defined by regionally continuous, thin, radioactive, black-shale marker beds that bound the unit.

Reservoir facies of the predominantly siliciclastic Cleveland Formation, in part, were deposited as a series of three eastward-prograding, probably wave-dominated deltas composed of (in ascending sequence) prodelta, distal delta-front, and proximal delta-front deposits. An upward-fining fluvial sandstone occurs in one stratigraphic zone in the middle Cleveland throughout most of the study area. Regional cross sections and net-sandstone patterns indicate four dominant sandstone trends in the producing area: three north-south-oriented, arcuate thicks composed of stacked delta-front facies at stabilized paleoshoreline positions, and one east-west trend representing superimposed fluvial-channel incision after a drop in regional base level.

Distinctive trends of thickness variation record elements of the paleophysiography of the Cleveland depositional area and evidence of syndepositional faulting, flexure, and marked differential subsidence. The unit thickens eastward toward the deep Anadarko basin and reaches a maximum thickness of about 590 ft in southwestern Hemphill County. Depositional patterns were controlled by (1) a paleohigh in the western part of the study area (eastern flank of Cimarron arch) that separates siliciclastic facies from carbonate-dominate Cleveland of the Kansas shelf, (2) subsidence of two subbasins within a northwest-trending half-graben bounded by a syndepositional fault on its southern edge and a monoclinal flexure on the north, and (3) a two-tiered depositional shelf that reflects differentia subsidence of an underlying Oswego Limestone buildup.

AAPG Search and Discovery Article #91018©1992 AAPG Southwest Section Meeting, Midland, Texas, April 21-24, 1992 (2009)