Triangle
Val-d'Or, Quebec (Abitibi greenstone belt), Canada
Orogenic goldAu
- Type
- Orogenic gold in shear-hosted quartz-tourmaline-carbonate veins
Deposit of the Val-d'Or vein field (3.0 Mt at 6.19 g/t Au, Simoneau et al., 2024): quartz-tourmaline-carbonate veins in the C2 and C4 shear zones, hosted by volcanic and volcaniclastic rocks (Triangle Tuff) and a dioritic intrusion (Triangle Plug), at greenschist facies; native gold and tellurides in pyrite. Pedemonte Castro et al. (2026): quartz-tourmaline temperatures from 196 to 417 °C, fluid from +1.3 to +9.9 ‰ in δ18O and from -8.6 to -3.6 ‰ in δ11B, mixing between a metamorphic fluid (δ18O near 10 ‰, δ11B near -9 ‰) and an upper-crustal pore fluid (near 2 ‰ and -3 ‰).
δ11B in ‰ (per mil) Values of the same system
Standard : NIST SRM 951
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| −9.5 ± 0.8 ‰ | −10.5 / −7.8 ‰ | 26 | tourmaline of quartz-tourmaline-carbonate veins (Triangle Tuff) Published mean, standard deviation and range. All data: cores from -11.7 to -8.0 ‰ (-10.1 ± 0.9 ‰, n = 25), rims from -12.6 to -7.8 ‰ (-10.4 ± 1.5 ‰, n = 41). | Pedemonte Castro et al. (2026), Fluid sources and evolution at the Triangle orogenic gold… |
| −10.5 ± 0.7 ‰ | −12.1 / −9 ‰ | 20 | tourmaline of quartz-tourmaline-carbonate veins (Triangle Plug) Published mean, standard deviation and range. All data: cores from -11.7 to -8.0 ‰ (-10.1 ± 0.9 ‰, n = 25), rims from -12.6 to -7.8 ‰ (-10.4 ± 1.5 ‰, n = 41). | Pedemonte Castro et al. (2026), Fluid sources and evolution at the Triangle orogenic gold… |
| −10.5 ± 1.1 ‰ | −12.6 / −8.2 ‰ | 22 | tourmaline of quartz-tourmaline-carbonate veins (tuff-plug contact) Published mean, standard deviation and range. All data: cores from -11.7 to -8.0 ‰ (-10.1 ± 0.9 ‰, n = 25), rims from -12.6 to -7.8 ‰ (-10.4 ± 1.5 ‰, n = 41). | Pedemonte Castro et al. (2026), Fluid sources and evolution at the Triangle orogenic gold… |
| −10.9 ± 1 ‰ | −12.4 / −9.1 ‰ | 11 | quartz-tourmaline-pyrite-chlorite vein tourmaline (sample 85, drill core, 208.5 m) Mean and standard deviation recalculated from 11 analyses, -12.4 to -9.1 (1 -9.1; 2 -12.0; 3 -11.6; 4 -11.2; 5 -12.4; 9 -11.1; 8 -10.9; 7 -10.6; 6 -10.9; 10 -10.1; 11 -9.6). Published mean -10.8 ± 0.9 ‰. | Daver et al. (2020), Three-stage formation of greenstone-hosted orogenic gold deposits in… |
| −11 ± 0.3 ‰ | −11.7 / −10.6 ‰ | 10 | tourmaline from a chlorite- and K-feldspar-rich quartz-tourmaline vein (sample 87, same drill core, 211.5 m) Mean and standard deviation recalculated from 10 analyses, -11.7 to -10.6 (1 -11.3; 2 -10.6; 3 -10.6; 4 -11.7; 5 -10.8; 6 -11.2; 7 -10.8; 8 -10.8; 9 -11.0; 10 -10.9). Published mean -10.9 ± 0.3 ‰. | Daver et al. (2020), Three-stage formation of greenstone-hosted orogenic gold deposits in… |
δ18O in ‰ (per mil) Values of the same system
Standard : V-SMOW
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| 12.9 ± 0.5 ‰ | 11.8 / 13.8 ‰ | 21 | vein quartz (types a, b and c), Triangle Tuff Published mean, standard deviation and range. Two outliers excluded (17.0 and 17.4 ‰). | Pedemonte Castro et al. (2026), Fluid sources and evolution at the Triangle orogenic gold… |
| 13 ± 0.7 ‰ | 11.8 / 14.1 ‰ | 19 | vein quartz (types a, b and c), Triangle Plug Published mean, standard deviation and range. | Pedemonte Castro et al. (2026), Fluid sources and evolution at the Triangle orogenic gold… |
| 13.1 ± 0.3 ‰ | 12.6 / 13.8 ‰ | 23 | vein quartz (types a, b and c), tuff-plug contact Published mean, standard deviation and range. | Pedemonte Castro et al. (2026), Fluid sources and evolution at the Triangle orogenic gold… |
| 9.9 ± 0.7 ‰ | 8.7 / 11.1 ‰ | 24 | vein tourmaline, Triangle Tuff Published mean, standard deviation and range. | Pedemonte Castro et al. (2026), Fluid sources and evolution at the Triangle orogenic gold… |
| 9.7 ± 0.7 ‰ | 8.5 / 11.1 ‰ | 20 | vein tourmaline, Triangle Plug Published mean, standard deviation and range. The text excludes an outlier at 11.0 ‰, although it lies within the published range. | Pedemonte Castro et al. (2026), Fluid sources and evolution at the Triangle orogenic gold… |
| 9.7 ± 0.7 ‰ | 8.2 / 10.8 ‰ | 22 | vein tourmaline, tuff-plug contact Published mean, standard deviation and range. One outlier excluded (6.8 ‰). | Pedemonte Castro et al. (2026), Fluid sources and evolution at the Triangle orogenic gold… |
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Cite this page
IsoFind Atlas (2026). Triangle, isotope signatures. https://www.isofind.tech/isotopes/en/deposits/triangle/ (accessed 2026-10-20).
@misc{isofind2026triangleisotopesignatures,
title = {Triangle, isotope signatures},
author = {{IsoFind Atlas}},
year = {2026},
url = {https://www.isofind.tech/isotopes/en/deposits/triangle/},
note = {Accessed 2026-10-20}
}Updated : 2026-10-20