AAPG Bulletin, V. 82 (1998), No. 2 (February 1998), P. 291-316.

Heat Flow and Thermal History of the Anadarko Basin, Oklahoma¹

Larry S. Carter,² Shari A. Kelley,³ David D. Blackwell,⁴ and Nancy D. Naeser⁵

©Copyright 1998.  The American Association of Petroleum Geologists.  All Rights Reserved

¹Manuscript received May 3, 1996; revised manuscript received January 16, 1997; final acceptance August 6, 1997.
²Marathon Oil Company, 909 ESE Loop 323, Suite 500, Tyler, Texas 75713.
³Department of Earth and Environmental Sciences, New Mexico Institute of Mining and Technology, Socorro, New Mexico 87801.
⁴Department of Geological Sciences, Southern Methodist University, Dallas, Texas 75275.
⁵U.S. Geological Survey, MS 926A, National Center, 12201 Sunrise Valley Drive, Reston, Virginia 20192.

We thank the following oil companies for allowing us to run temperature logs in their wells: Carl E. Gungoll Exploration Corporation, Continental Trend Resources Corporation, Shell Western Exploration and Production Company, Standard of Ohio Oil Production Company, Sundance Energy Corporation, and Ward Petroleum Corporation. The following companies provided technical support during the logging of the Ferris 1-28 well: Shell Western Exploration and Production Company, Cudd Pressure Control Incorporated, Sandia National Laboratory, and Madden Systems Incorporated. Computer software and facilities for the basin history modeling were provided by Oryx Energy Company. Brian Cardott shared unpublished vitrinite reflectance data and valuable discussions concerning the thermal maturity of the basin. Reneé Greyvensteyn and Marie Richards helped with the figures and tables. Core samples used in this study were obtained from the Oklahoma Geological Survey Core and Sample Library and from Standard of Ohio Oil Company. The Institute for the Study of Earth and Man at Southern Methodist University and the Mobil Foundation provided funding for field expenses and microprobe work. Fission-track sample collection and analysis were supported in part by the U.S. Geological Survey Evolution of Sedimentary Basins Program. Fission-track samples were irradiated under the Department of Energy reactor share program at Texas A&M University Nuclear Science Center. We appreciate the careful reviews of David Deming, Brian Cardott, and John Shelton. 

ABSTRACT

New heat-flow values for seven sites in the Anadarko basin, Oklahoma, were determined using high-precision temperature logs and thermal conductivity measurements from nearly 300 core plugs. Three of the sites are on the northern shelf, three sites are in the deep basin, and one site is in the frontal fault zone of the northern Wichita Mountains. The heat flow decreased from 55 to 64 mW/m² in the north, and from 39 to 54 mW/m² in the south, due to a decrease in heat generation in the underlying basement rock toward the south. Lateral lithologic changes in the basin, combined with the change in heat flow across the basin, resulted in an unusual pattern of thermal maturity. The vitrinite reflectance values of the Upper Devonian- Lower Mississippian Woodford formation are highest 30-40 km north-northwest of the deepest part of the basin. The offset in highest reflectance values is due to the contrast in thermal conductivity between the Pennsylvanian "granite wash" section adjacent to the Wichita uplift and the Pennsylvanian shale section to the north. The geothermal gradient in the low-conductivity shale section is elevated relative to the geothermal gradient in the high-conductivity "granite wash" section, thus displacing the highest temperatures to the north of the deepest part of the basin.

Apatite fission-track, vitrinite reflectance, and heat-flow data were used to constrain regional aspects of the burial history of the Anadarko basin. By combining these data sets, we infer that at least 1.5 km of denudation has occurred at two sites in the deep Anadarko basin since the early to middle Cenozoic (40 ±10 m.y.). The timing of the onset of denudation in the southern Anadarko basin coincides with the period of late Eocene erosion observed in the southern Rocky Mountains and in the northern Great Plains.

Burial history models for two wells from the deep Anadarko basin predict that shales of the Woodford formation passed through the hydrocarbon maturity window by the end of the Permian. The Late Pennsylvanian-Early Permian section in the deep basin moved into the hydrocarbon maturity window during Mesozoic burial of the region. Presently, the depth interval of the main zone of oil maturation (% R_o = 0.7-0.9) is approximately 2800-3800 m in the eastern deep basin and 2200-3000 m in the western deep basin. The greater depth to the top of the oil maturity zone and larger depth range of the zone in the eastern part of the deep basin are due to the lower heat flow associated with more mafic basement toward the east. The burial history model for the northern shelf indicates that the Woodford formation has been in the early oil maturity zone since the Early Permian.