Macusani uranium district (Macusani Meseta)
Puno, Cordillera de Carabaya, Peru
UraniumU
- Type
- Peraluminous volcanic-hosted uranium (autunite)
Uranium ore sample from the Queen's University collection analysed by Uvarova et al. (2014) for δ238U and δ234U. Autunite in fractures or disseminated in units A and B of Miocene peraluminous rhyolites (Leroy and George-Aniel, 1992), Chilcuno, Tuturmani, Nuevo Corani, Isivilla, Calibri and Pinocho prospects; deposition below 50 °C. δ238U from -0.30 to +0.46 ‰ (mean +0.18 ‰), lower than the source rhyolites (+0.44 to +2.10 ‰); δ234U near equilibrium, a few samples depleted in 234U. Indicative coordinates (Macusani).
δ238U in ‰ (per mil) Values of the same system
Standard : NBL CRM 112-A
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| −0.03 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample M206-1, Macusani; bracketing-only δ238U at +0.07; 238U/235U of 137.832; about -0.63 ‰ after removing the 0.60 ‰ offset specific to this study. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −0.07 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample M206-2, Macusani; bracketing-only δ238U at -0.03; 238U/235U of 137.827; about -0.67 ‰ after removing the 0.60 ‰ offset specific to this study. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −0.12 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample M207, Macusani; bracketing-only δ238U at -0.24; 238U/235U of 137.82; about -0.72 ‰ after removing the 0.60 ‰ offset specific to this study. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 0.46 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample Chi-5, Chilcuno prospect; bracketing-only δ238U at +0.42; 238U/235U of 137.9; about -0.14 ‰ after removing the 0.60 ‰ offset specific to this study. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 0.26 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample Chi-6-1, Chilcuno prospect; bracketing-only δ238U at +0.31; 238U/235U of 137.872; about -0.34 ‰ after removing the 0.60 ‰ offset specific to this study. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 0.41 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample Chi-6, Chilcuno prospect; bracketing-only δ238U at +0.22; 238U/235U of 137.893; about -0.19 ‰ after removing the 0.60 ‰ offset specific to this study. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 0.02 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample Tut-1, Tuturmani prospect; bracketing-only δ238U at +0.01; 238U/235U of 137.839; about -0.58 ‰ after removing the 0.60 ‰ offset specific to this study. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 0.09 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample NC-1, Nuevo Corani; bracketing-only δ238U at -0.09; 238U/235U of 137.848; about -0.51 ‰ after removing the 0.60 ‰ offset specific to this study. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 0.12 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample Is-2, Isivilla prospect; bracketing-only δ238U at 0.00; 238U/235U of 137.853; about -0.48 ‰ after removing the 0.60 ‰ offset specific to this study; first of the two Is-2 rows of the table. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 0.26 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample 10-Is-10, Isivilla prospect; bracketing-only δ238U at +0.17; 238U/235U of 137.873; about -0.34 ‰ after removing the 0.60 ‰ offset specific to this study. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 0.41 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample 10-Is-17, Isivilla prospect; bracketing-only δ238U at +0.23; 238U/235U of 137.893; about -0.19 ‰ after removing the 0.60 ‰ offset specific to this study. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 0.38 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample Is-2, Isivilla prospect; bracketing-only δ238U at +0.11; 238U/235U of 137.889; about -0.22 ‰ after removing the 0.60 ‰ offset specific to this study; second of the two Is-2 rows of the table, unexplained. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 0.23 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample Clb-2, Calibri prospect; bracketing-only δ238U at +0.13; 238U/235U of 137.869; about -0.37 ‰ after removing the 0.60 ‰ offset specific to this study; first of the two Clb-2 rows of the table. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 0.36 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample Clb-2, Calibri prospect; bracketing-only δ238U at +0.11; 238U/235U of 137.887; about -0.24 ‰ after removing the 0.60 ‰ offset specific to this study; second of the two Clb-2 rows of the table, unexplained. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −0.3 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample Pi-1, Pinocho prospect; bracketing-only δ238U at -0.34; 238U/235U of 137.795; about -0.90 ‰ after removing the 0.60 ‰ offset specific to this study; lowest autunite value. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 0.44 ± 0.1 ‰ | 1 | autunite Single analysis; ± 0.10 ‰ (2 SD, reproducibility); sample Pi-2, Pinocho prospect; bracketing-only δ238U at +0.42; 238U/235U of 137.897; about -0.16 ‰ after removing the 0.60 ‰ offset specific to this study. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… |
δ234U in ‰ (per mil) Values of the same system
Standard : équilibre séculaire
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| 1 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample M206-1, Macusani. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −5 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample M206-2, Macusani. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −4 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample M207, Macusani. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −4 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample Chi-5, Chilcuno prospect. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −17 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample Chi-6-1, Chilcuno prospect. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −2 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample Chi-6, Chilcuno prospect. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 1 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample Tut-1, Tuturmani prospect. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −1 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample NC-1, Nuevo Corani. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 9 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample Is-2, Isivilla prospect; first of the two Is-2 rows of the table. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −10 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample 10-Is-10, Isivilla prospect. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −7 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample 10-Is-17, Isivilla prospect. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 7 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample Is-2, Isivilla prospect; second of the two Is-2 rows of the table, unexplained. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −26 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample Clb-2, Calibri prospect; 234U deficit: uranium loss within the last 2.5 Myr; first of the two Clb-2 rows of the table. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −24 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample Clb-2, Calibri prospect; 234U deficit: uranium loss within the last 2.5 Myr; second of the two Clb-2 rows of the table, unexplained. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| −2 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample Pi-1, Pinocho prospect; lowest autunite value. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… | |
| 0 ‰ | 1 | autunite Single analysis; per-sample uncertainty not published; sample Pi-2, Pinocho prospect. | Uvarova et al. (2014), Variations in the uranium isotopic compositions of uranium ores fr… |
Deposits of the same type
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- Faraday Canada
- Madawaska Canada
- Bancroft (uraniferous pegmatites) Canada
- Jackpile-Paguate (Jackpile mine) United States
- Denison Canada
- Milliken Lake Canada
- Stanleigh Canada
Cite this page
IsoFind Atlas (2026). Macusani uranium district (Macusani Meseta), isotope signatures. https://www.isofind.tech/isotopes/en/deposits/district-uranifere-de-macusani-meseta-de-macusani/ (accessed 2026-10-16).
@misc{isofind2026macusaniuraniumdistrictmacusa,
title = {Macusani uranium district (Macusani Meseta), isotope signatures},
author = {{IsoFind Atlas}},
year = {2026},
url = {https://www.isofind.tech/isotopes/en/deposits/district-uranifere-de-macusani-meseta-de-macusani/},
note = {Accessed 2026-10-16}
}Updated : 2026-10-16