| Basis for focus area |
The focus area includes the Crow Butte and Marsland deposits, outcrops of the White River Group and areas of the Crawford Basin where host sandstone is thickest (Dickinson, 1993). The Crow Butte deposit is in the lower sandstone member of the Oligocene Chadron Formation, sandwiched between shale aquitards in the overlying middle Chadron and underlying Pierre Shale. |
| Identified resources |
Identified resources and historical production of uranium. |
| Production |
The Crow Butte mine produced about 17 million pounds of U3O8 between 1986 and 2016 (Pool, 2017). |
| Status |
Past mining. |
| Estimated resources |
Crow Butte has Measured and Indicated in-place resources of ~14 million pounds of U3O8, and an additional 1.4 million pounds in the Inferred category (Cameco, 2020). |
| Geologic maps |
Horton and others (2017), scale 1:500,000. |
| Geophysical data |
Inadequate aeromagnetic and aeroradiometric coverage. |
| Favorable rocks and structures |
Oligocene Chadron Formation. |
| Deposits |
Crow Butte mine. |
| Evidence from mineral occurrences |
International Atomic Energy Agency (2020b); U.S. Environmental Protection Agency (2006). |
| Geochemical evidence |
No data. |
| Geophysical evidence |
No data. |
| Evidence from other sources |
No data. |
| Cover thickness and description |
The Crow Butte Deposit is 600-700 ft below the land surface. |
| Authors |
Susan Hall. |
| New data needs |
High resolution geophysical surveys. |
| Geologic mapping and modeling needs |
Not needed. |
| Geophysical survey and modeling needs |
High-resolution, Rank 1 aeromagnetic and radiometric surveys. |
| Digital elevation data needs |
Lidar adequate. |
