Stratigraphic cross sections of the Mowry Shale and associated strata in the Wind River Basin, Wyoming

Thomas M. Finn

doi:10.3133/sim3476

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Stratigraphic cross sections of the Mowry Shale and associated strata in the Wind River Basin, Wyoming

Thomas M. Finn

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Abstract

The Wind River Basin in Wyoming is one of many structural and sedimentary basins that formed in the Rocky Mountain foreland during the Laramide orogeny in the latest Cretaceous through the early Eocene. The basin (bounded by the Washakie, Owl Creek, and Bighorn uplifts on the north, the Casper arch on the east, the Granite Mountains uplift on the south, and Wind River uplift on the west) encompasses about 7,400 square miles in central Wyoming. The two stratigraphic cross sections presented in this report were constructed as part of a project carried out by the U.S. Geological Survey to characterize and evaluate the undiscovered continuous (unconventional) oil and gas resources of the Mowry Shale in the Wind River Basin in central Wyoming. The purpose of the cross sections is to show the stratigraphic relationship of the Mowry Shale and associated Lower and lowermost Upper Cretaceous strata in the Wind River Basin. These two cross sections were constructed using borehole geophysical logs from 41 wells drilled for oil and gas exploration and production, and one research well that was cored and logged by the U.S. Geological Survey. Both lines originate at Sheldon Dome in the northwestern part of the basin and end near Bates Creek in the extreme southeastern part of the basin. The stratigraphic interval extends from the uppermost part of the Upper Jurassic Morrison Formation to the basal part of the Upper Cretaceous Frontier Formation. The datum is the top of the Clay Spur Bentonite Bed, a distinctive bed at the top of the Upper Cretaceous Mowry Shale. A gamma ray and (or) spontaneous potential log was used in combination with a resistivity log to identify and correlate units.

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Source-reported bounding extent: 42.049292638686836° to 43.75522505306928° latitude; -109.8193359375° to -105.71044921875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Thomas M. Finn. 2021-07-28. Stratigraphic cross sections of the Mowry Shale and associated strata in the Wind River Basin, Wyoming. https://doi.org/10.3133/sim3476

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