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Geologic Assessment of Undiscovered Oil and Gas in the Powder River Basin Province, Wyoming and Montana

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Geologic Assessment of Undiscovered Oil and Gas in the Powder River Basin Province, Wyoming and Montana Geologic Assessment of Undiscovered Oil and Gas in the Powder River Basin Province, Wyoming and Montana By Lawrence O. Anna Chapter 1 Digital Data Series DDS–69–U U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Suzette M. Kimball, Acting Director U.S. Geological Survey, Reston, Virginia: 2009 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1-888-ASK-USGS For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. Suggested citation: Lawrence O. Anna, 2009, Geologic assessment of undiscovered oil and gas in the Powder River Basin Province: U.S. Geological Survey Digital Data Series DDS–69–U, 93 p. iii Contents Abstract ...........................................................................................................................................................1 Introduction.....................................................................................................................................................1 Pennsylvanian-Permian Composite Total Petroleum System ...............................................................2 Petroleum Source Rocks .....................................................................................................................3 Source Rock Thermal Maturity ..........................................................................................................8 Hydrocarbon Migration........................................................................................................................9 Reservoir Rocks ....................................................................................................................................9 Minnelusa Formation..........................................................................................................................10 Tensleep Sandstone ...........................................................................................................................14 Leo Formation ......................................................................................................................................14 Traps and Seals ...................................................................................................................................14 Mowry Total Petroleum System ...............................................................................................................17 Petroleum Source Rocks ...................................................................................................................17 Source Rock Thermal Maturity ........................................................................................................18 Hydrocarbon Migration......................................................................................................................20 Reservoir Rocks ..................................................................................................................................21 Fall River–Lakota Sandstones ................................................................................................21 Muddy Sandstone .....................................................................................................................22 Traps and Seals ...................................................................................................................................27 Mowry TPS as a Continuous Reservoir ..........................................................................................27 Niobrara Total Petroleum System .............................................................................................................28 Source Rocks.......................................................................................................................................28 Source Rock Thermal Maturity ........................................................................................................32 Hydrocarbon Migration......................................................................................................................32 Reservoir Rocks ..................................................................................................................................34 Frontier Formation......................................................................................................................34 Belle Fourche Member .............................................................................................................37 Emigrant Gap Member ..............................................................................................................37 Wall Creek Sandstone Member ..............................................................................................37 Turner Sandy Member ..............................................................................................................37 Cody Shale ...........................................................................................................................................38 Shannon Sandstone Member ..................................................................................................38 Sussex Sandstone Member .....................................................................................................38 Mesaverde Formation ........................................................................................................................41 Parkman Sandstone Member ..................................................................................................41 Teapot Sandstone Member ......................................................................................................41 Lewis Shale ..........................................................................................................................................42 Teckla Sandstone Member ......................................................................................................42 Traps and Seals ...................................................................................................................................42 Niobrara Total Petroleum System as a Continuous Reservoir ....................................................44 Paleozoic-Mesozoic Composite Total Petroleum System ...........................................................44 Petroleum Source Rocks ...................................................................................................................47 iv Source Rock Thermal Maturity ........................................................................................................48 Hydrocarbon Migration......................................................................................................................48 Reservoir Rocks ..................................................................................................................................49 Traps and Seals ...................................................................................................................................49 Tertiary-Upper Cretaceous Coalbed Methane Total Petroleum System ...........................................49 Cretaceous Biogenic Gas Total Petroleum System ..............................................................................49 Assessment of Undiscovered Petroleum Resource ..............................................................................50 Assessment of Undiscovered Petroleum Resources in Conventional Assessment Units ..............52 Minnelusa-Tensleep-Leo Sandstone AU (50330501) .....................................................................52 Fall River–Lakota Sandstones AU (50330201) .......................................................................53 Muddy Sandstone AU (50330202) ............................................................................................53 Frontier-Turner Sandstones AU (50330301) ...........................................................................54 Sussex-Shannon Sandstones AU (50330302) ........................................................................56 Mesaverde-Lewis Sandstones AU (50330303) ......................................................................57 Basin Margin AU (50330601) ....................................................................................................58 Eastern Basin Margin Upper Fort Union Sandstone AU (50330101) ..................................58 Conventional Assessment Summary ...............................................................................................58 Assessment of Undiscovered Petroleum Resources in Continuous Assessment Units .................59 Mowry Continuous Oil AU (50330261) ..............................................................................................59 Niobrara Continuous Oil AU (50330361) ..........................................................................................59
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