Geologic and Structural Controls for the CO2 Sequestration Potential of the Permian Cutler Group White Rim and De Chelly Sandstones in Southeastern Utah

Peter Nielsen, Stephenie Carney, and Craig Morgan

The Permian White Rim and De Chelly Sandstones are potential CO2 sequestration resevoirs in southeastern Utah. The sandstones are regionally extensive, permeable to some extent, and overlain by thick sequences of siltstone, mudstone, and shale. Depending of the amount of overburden, injection of CO2 could be accomplished within a reasonable zone of pressure and injection rate. The White Rim Sandstone represents an eolian deposit with fluvial or marine reworked sands at the top. The White Rim was a large dune field on the northwest edge of the Uncompahgre Highlands. The White Rim interfingers with the marine deposits of the Black Box Dolomite to the north and west in the San Rafael Swell area, pinches out to the southeast, and grades into or interfingers with the Kaibab Formation to the southwest. The De Chelly Sandstone represents a large eolian dune deposit between the southeastern end of the Uncompahgre Highlands and the Kaibab Sea to the southwest. The De Chelly consists of dune sands over lain with fluvial or marine reworked sands at the top. The dune sands are occasionally interbedded with sabkha or mud-flat type deposits near their eastern extent. The White Rim has been the target for oil exploration in the northern part of the Paradox Basin. The White Rim and De Chelly Sandstones are being examined in outcrop and in the subsurface using the numerous oil and exploration wells in the area. The depositional environments of the sandstones suggest that porosity and permeability vary laterally and vertically through the units. Our ongoing study objectives are: 1) determine the extent, thickness, and amount of overburden, 2) estimate the distribution of density, temperature, porosity, permeability, formation pressure, and water saturation, and 3) estimate the CO2 storage potential for the regional extents of the sandstone units. We will present the results of our current research of the White Rim and De Chelly Sandstones and suggest areas of continued field and laboratory research.

AAPG Search and Discovery Article #90156©2012 AAPG Rocky Mountain Section Meeting, Grand Junction, Colorado, 9-12 September 2012