Fe isotope behaviours during sulfide-dominated skarn-type mineralisation

Wang, Yue, Zhu, Xiang-kun, and Cheng, Yanbo (2015) Fe isotope behaviours during sulfide-dominated skarn-type mineralisation. Journal of Asian Earth Sciences, 103. pp. 374-392.

[img] PDF (Published Version) - Published Version
Restricted to Repository staff only

View at Publisher Website: http://dx.doi.org/10.1016/j.jseaes.2014....
 
7
1


Abstract

Fe isotope compositions of mineral separates and bulk samples from Dongguashan and Fenghuangshan skarn type Cu–Fe deposits in Tongling District, Middle–Lower Yangtze Valley Cu–Fe–Au–Mo polymetallic belt have been investigated. Differences in δ^57Fe values exist in co-precipitated bornite–chalcopyrite and pyrite–chalcopyrite mineral pairs. The bornite is enriched in light iron isotopes relative to coexisting chalcopyrite, whereas pyrite samples show a tendency of heavy isotopes enrichment relative to chalcopyrite. Moreover, the δ^57Fe values of endoskarn and the earliest formed Fe-mineral phase magnetite of the three deposits investigated in Tongling district are consistently lower relative to ore-related igneous rocks, suggesting Fe isotopic fractionation occurs during fluid exsolution and exsolved fluid is enriched in light Fe isotopes relative to the stock. Furthermore, spatial and temporal variations in δ^57Fe values within single mineral phases are observed, suggesting iron isotopic fractionation occurs between mineral and fluid phases as a result of precipitation of Fe-bearing minerals during fluid evolution. Overall, according to Fe isotope compositions of three representative skarn deposits formed under the same geological setting in Tongling district, this study indicates that Fe isotopes have the potential to unraveling ore-forming processes, as well as constraining the metal sources of skarn deposits. Combining with results of previous studies, a protocol for using Fe isotopes to trace skarn-type metallogeny is proposed.

Item ID: 40104
Item Type: Article (Research - C1)
ISSN: 1878-5786
Keywords: iron isotopes; skarn deposit; tongling district; fluid exsolution; fluid evolution
Funders: Major State Basic Research Program (MSBRP), National Department Public Benefit Research Foundation (NDPBRF), National Natural Science Fund of China (NNSFC), Scientific Research Fund (SRF)
Projects and Grants: MSBRP 2012CB416806, NDPBRF 201011027, NDPBRF 201311144, NNSFC No. 41203006, SRF J1201
Date Deposited: 25 Aug 2015 23:27
FoR Codes: 04 EARTH SCIENCES > 0403 Geology > 040307 Ore Deposit Petrology @ 100%
SEO Codes: 84 MINERAL RESOURCES (excl. Energy Resources) > 8401 Mineral Exploration > 840199 Mineral Exploration not elsewhere classified @ 100%
Downloads: Total: 1
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page