In:
Scientific Reports, Springer Science and Business Media LLC, Vol. 5, No. 1 ( 2015-09-08)
Abstract:
Lithium isotopic compositions of fluid inclusions and hosted gangue quartz from a giant volcanogenic massive sulfide deposit in China provide robust evidence for inputting of magmatic fluids into a Triassic submarine hydrothermal system. The δ 7 Li results vary from +4.5‰ to +13.8‰ for fluid inclusions and from +6.7‰ to +21.0‰ for the hosted gangue quartz(9 gangue quartz samples containing primary fluid inclusions). These data confirm the temperature-dependent Li isotopic fractionation between hydrothermal quartz and fluid (i.e., Δδ 7 Li quartz-fluid = –8.9382 × (1000/T) + 22.22(R 2 = 0.98; 175 °C–340 °C)), which suggests that the fluid inclusions are in equilibrium with their hosted quartz, thus allowing to determine the composition of the fluids by using δ 7 Li quartz data. Accordingly, we estimate that the ore-forming fluids have a δ 7 Li range from −0.7‰ to +18.4‰ at temperatures of 175–340 °C. This δ 7 Li range, together with Li–O modeling , suggest that magmatic fluid played a significant role in the ore formation. This study demonstrates that Li isotope can be effectively used to trace magmatic fluids in a seafloor hydrothermal system and has the potential to monitor fluid mixing and ore-forming process.
Type of Medium:
Online Resource
ISSN:
2045-2322
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
2015
detail.hit.zdb_id:
2615211-3
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