AAPG Bulletin; January 2009; v. 93; no. 1;
p. 1-29; DOI: 10.1306/09030808054
© 2009 American Association of Petroleum Geologists (AAPG)
Middle Atokan sediment gravity flows in the Red Oak field, Arkoma Basin, Oklahoma: A sedimentary analysis using electrical borehole images and wireline logs
Chunming Xu1,
Thomas P. Cronin2,
Thalbert E. McGinness3 and
Brad Steer4
1 Shell, 220 North Dairy Ashford, Houston, Texas 77079; Chunming.Xu{at}shell.com
2 BP America Production Co., P.O. Box 3092, Houston, Texas, 77253-3092; Tom.Cronin{at}bp.com
3 BP America Inc., 501 Westlake Park Blvd., Houston, Texas 77079
4 TNK-BP, 1 Arbart Street, Moscow, 103045, Russia
Chunming Xu received a B.S. degree in geophysics in 1982 from the Jianhan Petroleum College, China. He worked with PetroChina for 10 years as a geophysicist on prospect evaluation and thrust tectonics in northwestern China and the Canadian Rockies and Canadian Foothills. He joined Schlumberger in 1992 as a geologist focused on stratigraphic interpretation and reservoir characterization using borehole images and open-hole logs in various sedimentary environments. Since he joined Shell in early 2006, he has been working on image log interpretation guidelines in coastal and deep-water clastic reservoirs for integrated reservoir modeling.
Thomas Cronin is a senior geologist with BP in Houston and holds a B.A. degree (1980) and an M.S. degree (1983) in geology from the University of Tennessee. He has more than 25 years of experience in the petroleum industry with Gulf Oil, Amoco Production Co., Burlington Resources, and BP. In addition to his current assignment in field development in the Arkoma Basin, he has worked on development and exploration assignments in the U.S. Gulf of Mexico, Indonesia, Vietnam, Thailand, Bangladesh, China, and Trinidad.
Thalbert E. (Thal) McGinness has 40 years of experience in the oil and gas industry. A senior petrophysical associate with BP, he joined Schlumberger in 1969 and Amoco Production Co. in 1979. He holds a B.S. degree from East Central State University and an M.S. degree in natural science from Eastern New Mexico State University. He retired from BP in 2008.
Brad Steer holds degrees in geology from San Diego State University (M.S. degree, 1979), University of Utah (B.S. degree, 1976), and University of Northern Colorado (B.A. degree, 1974). He has been with BP (formerly Amoco) since 1980. He has worked in numerous basins, including the Suez rift, Egypt, the Columbus Basin, Trinidad, and the Arkoma Basin, Oklahoma. He is currently working with TNK-BP in Moscow, Russia.
An integrated analysis of the borehole images and open-hole logs in the Red Oak gas field has revealed the detailed sedimentary characteristics of the middle Atokan (Lower Pennsylvanian) Red Oak and Fanshawe turbidites and mass transport in the Arkoma Basin. The older Red Oak sandstone member is a multistory channel complex characterized by abundant sandy scour-and-fills with inclined bedding, mudstone-clast-rich channel fills, intrachannel mudstone drapes, and localized debrites. The younger Fanshawe turbidite system deposited a large thickness of thin-bedded sandstones and mudstones in and near a southward-trending canyon and distributary system right above the Red Oak sand depocenter. The consistent south-vergent syndepositional slump movements and associated rollover beds suggest deposition on a south-dipping paleoslope.
Based on the interpretation of sedimentary textures and lithology from the multiwell borehole images and open-hole logs, 10 rock facies are classified to analyze the channel and nonchannel elements. Bedding and scour surfaces on the borehole images are classified to analyze the structural and depositional processes. Although the inclined sand bedding over scour surfaces appears similar to trough cross-bedding structures, the widely dispersed azimuth of the inclined bedding sets in the Red Oak channel sandstones suggests an irregular scour-and-fill process with unclear relation to paleocurrent directions. Linked debrites at different stages of flow transformation provide valuable insights of the depositional mechanism. Various types of syndepositional deformation structures at different scales are interpreted to help understand the structural and depositional environments. The multiwell characterization of the image facies and the vertical sequences allowed the well-to-well correlation and mapping of the Red Oak and Fanshawe turbidite systems across the field.
Copyright © 2009 by American Association of Petroleum Geologists (AAPG)
