Furnas
Pará, Carajás Northern Copper Belt (Amazonian Craton), Brazil
IOCGCu-Au
- Type
- IOCG (Cu-Au)
Neoarchean IOCG deposit of the Carajás Province (see also the Carajás entry); main mineralization around 2.55 Ga within Fe-K then chlorite alteration halos. Volcano-sedimentary sequences and granitoids with Fe-K alteration, silicification and late chloritization; lens-shaped copper-gold orebodies enveloped by Fe-K alteration with disseminated tourmaline. Melo et al. (2021): tourmaline from +13.1 to +17.2 ‰.
δ11B in ‰ (per mil) Values of the same system
Standard : NIST SRM 951
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| 15.2 ± 0.9 ‰ | 13.1 / 17.2 ‰ | 17 | disseminated tourmaline of the Fe-K alteration, sample FD39-118 Mean and standard deviation recalculated from 17 analyses, +13.1 to +17.2 (FD39-118-1 g1 +15.2; FD39-118-2 g1 +15.4; FD39-118-3 g1 +14.7; FD39-118-4 g1 +14.3; FD39-118-5 g1 +14.6; FD39-118-6 g1 +15.1; FD39-118-7 g1 +15.1; FD39-118-8 g2 +15.0; FD39-118-9 g2 +15.3; FD39-118-10 g2 +16.4; FD39-118-11 g2 +15.5; FD39-118-12 g2 +14.6; FD39-118-13 g2 +15.3; FD39-118-14 g2 +16.3; FD39-118-15 g2 +17.2; FD39-118-16 g3 +13.1; FD39-118-17 g3 +15.1). Grain number noted g. | Melo et al. (2021), Magmatic-hydrothermal fluids leaching older seafloor exhalative rocks… |
Deposits of the same type
- Grota Funda Brazil
- Bacaba Brazil
- Sossego Brazil
- Salobo Brazil
- Castanha Brazil
- Igarapé Bahia Brazil
- Alvo 118 Brazil
- GT-46 Brazil
Cite this page
IsoFind Atlas (2026). Furnas, isotope signatures. https://www.isofind.tech/isotopes/en/deposits/furnas/ (accessed 2026-10-20).
@misc{isofind2026furnasisotopesignatures,
title = {Furnas, isotope signatures},
author = {{IsoFind Atlas}},
year = {2026},
url = {https://www.isofind.tech/isotopes/en/deposits/furnas/},
note = {Accessed 2026-10-20}
}Updated : 2026-10-20