Phosphoria Formation
Western United States (Lakeridge 43-19-G well and outcrops), United States
OtherP
- Type
- Marine sedimentary phosphorite (carbonate fluorapatite)
Phosphate rocks studied by Hill et al. (2024) to reconstruct redox conditions and diagenesis: U, Sr and rare earths carried by carbonate fluorapatite; samples taken at mines or from the Julius Kühn Institute archives. Guadalupian (Middle Permian, 260 to 272 Ma); high V, Cr, Mo and Cd in some samples (up to 2645 mg/kg V). Coordinates not given.
87Sr/86Sr isotope ratio, no unit Values of the same system
Standard : NIST SRM 987
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| 0.708022 ± 0.000368 | 0.70765 / 0.708609 | 7 | phosphate rock (bulk) Mean and standard deviation recalculated from 7 analyses, samples US-12, US-13, US-14, US-15, US-16, US-17, US-18. | Hill et al. (2024), Reconstructing the depositional environment and diagenetic modificati… |
| 0.70784 ± 0.00035 | 0.707382 / 0.708268 | 7 | extracted carbonate fluorapatite (CFA) Mean and standard deviation recalculated from 7 analyses, samples US-12, US-13, US-14, US-15, US-16, US-17, US-18. | Hill et al. (2024), Reconstructing the depositional environment and diagenetic modificati… |
δ238U in ‰ (per mil) Values of the same system
Standard : NBL CRM 112-A
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| −0.048 ± 0.115 ‰ | −0.16 / 0.07 ‰ | 3 | extracted carbonate fluorapatite (CFA) Mean and standard deviation recalculated from 3 analyses, samples US-12, US-17, US-18; modern seawater at -0.38 ‰ for comparison. | Hill et al. (2024), Reconstructing the depositional environment and diagenetic modificati… |
δ234U in ‰ (per mil) Values of the same system
Standard : équilibre séculaire
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| 3.08 ± 5.75 ‰ | −3.3 / 7.88 ‰ | 3 | extracted carbonate fluorapatite (CFA) Mean and standard deviation recalculated from 3 analyses, samples US-12, US-17, US-18; a departure from 0 signals uranium mobility within the last two million years. | Hill et al. (2024), Reconstructing the depositional environment and diagenetic modificati… |
Deposits of the same type
- Central African Copperbelt (whole province) DR Congo and Zambia
- Witwatersrand basin South Africa
- Stelvio Italy
- Oris Italy
- Kupferschiefer, Lubin-Sieroszowice district Poland
- Timna Israël
- Datangpo-type manganese (Gaolou, Minle, Zhenxing) China
- Eyller Bruch bog iron ore Germany
Cite this page
IsoFind Atlas (2026). Phosphoria Formation, isotope signatures. https://www.isofind.tech/isotopes/en/deposits/formation-de-phosphoria/ (accessed 2026-10-15).
@misc{isofind2026phosphoriaformationisotopesig,
title = {Phosphoria Formation, isotope signatures},
author = {{IsoFind Atlas}},
year = {2026},
url = {https://www.isofind.tech/isotopes/en/deposits/formation-de-phosphoria/},
note = {Accessed 2026-10-15}
}Updated : 2026-10-15