Slick Rock (district)
Colorado, San Miguel and Dolores counties (Uravan mineral belt, Colorado Plateau), United States
UraniumU-V
- Type
- Sandstone-hosted uranium-vanadium (tabular and roll ore bodies)
Uranium-vanadium district of the Salt Wash Member (Morrison Formation, Upper Jurassic), producing radium, vanadium and then uranium since the early twentieth century (Burro, Cougar, Ike, King, Brighton, Mayday mines). Tabular and roll ore bodies deposited at the interface between formation water and a solution introduced along the Dolores fault system; red-beds, carbon and altered sandstone facies. Ore age probably Oligocene, close to the La Sal laccoliths (28 to 25 Ma). Shawe (2011): sandstone barite at delta34S +9.8 to +13.5 ‰, like Hermosa Group sulphates; lead mostly common, except inside one roll (uranogenic lead).
δ34S in ‰ (per mil) Values of the same system
Standard : V-CDT
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| 12.62 ‰ | 11.47 / 13.4 ‰ | 5 | barite of red-beds-facies sandstone, Disappointment Valley drill cores Published mean and range (5 samples), without individual values. Hermosa Group sulphates about +11 to +13 ‰: barite probably introduced long before the ore. | Shawe (2011), Uranium-vanadium deposits of the Slick Rock district, Colorado, U.S. Geolog… |
| 12.2 ‰ | 10.9 / 13.5 ‰ | 2 | barite of carbon-facies sandstone Published mean and range (2 samples), without individual values. Hermosa Group sulphates about +11 to +13 ‰: barite probably introduced long before the ore. | Shawe (2011), Uranium-vanadium deposits of the Slick Rock district, Colorado, U.S. Geolog… |
| 11.02 ‰ | 9.8 / 12 ‰ | 5 | barite of altered-facies sandstone (two from the Brushy Basin Member) Published mean and range (5 samples), without individual values. Hermosa Group sulphates about +11 to +13 ‰: barite probably introduced long before the ore. | Shawe (2011), Uranium-vanadium deposits of the Slick Rock district, Colorado, U.S. Geolog… |
206Pb/207Pb isotope ratio, no unit Values of the same system
Standard : Non précisé dans la publication
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| 1.32 ± 0.08 | 1.23 / 1.38 | 3 | galena and clausthalite (concave edge of the Burro No. 3 roll, Cougar mine nodules) Mean and standard deviation recalculated from 3 analyses, 1.23 to 1.38 (615 (galène et clausthalite) 1.38; 614 (galène et clausthalite) 1.36; Cougar (galène) 1.23). Common lead, like base-metal mines of the San Juan Mountains. Ratios to 204Pb: 615: 204/207 0.063, 204/208 0.026; 614: 204/207 0.064, 204/208 0.026; Cougar: 204/207 0.065, 204/208 0.026. Unpublished second-hand values, not verified. | Shawe (2011), Uranium-vanadium deposits of the Slick Rock district, Colorado, U.S. Geolog… |
| 3.66 | 1 | clausthalite 30 cm inside the Burro No. 3 roll Single analysis (616 (clausthalite)). Uranogenic lead (204/207 0.055, 204/208 0.026): input from a uranium-rich source on the formation-water side. Unpublished second-hand value, not verified. | Shawe (2011), Uranium-vanadium deposits of the Slick Rock district, Colorado, U.S. Geolog… |
(234U/238U) isotope ratio, no unit Values of the same system
Standard : Équilibre séculaire (rapport d'activité = 1)
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| 0.95 / 1.02 | unoxidised ore of the Burro No. 7 roll From a 5 % deficit to a 2 % excess of 234U, read here as an activity ratio of 0.95 to 1.02: little leaching since deposition, strongly reducing setting. Second-hand value, not verified. | Shawe (2011), Uranium-vanadium deposits of the Slick Rock district, Colorado, U.S. Geolog… |
Deposits of the same type
- Athabasca basin (unconformity uranium province) Canada
- Shea Creek (Athabasca) Canada
- Tim Mersoï basin (Arlit, Akouta, Imouraren) Niger
- Inkai (Chu-Sarysu basin) Kazakhstan
- Tulukuevskoye Russia
- Ty Gallen France
- Rophin France
- Key Lake (Deilmann and Gaertner) Canada
Cite this page
IsoFind Atlas (2026). Slick Rock (district), isotope signatures. https://www.isofind.tech/isotopes/en/deposits/slick-rock-district/ (accessed 2026-10-21).
@misc{isofind2026slickrockdistrictisotopesigna,
title = {Slick Rock (district), isotope signatures},
author = {{IsoFind Atlas}},
year = {2026},
url = {https://www.isofind.tech/isotopes/en/deposits/slick-rock-district/},
note = {Accessed 2026-10-21}
}Updated : 2026-10-21