Bibliographische Detailangaben
|
Personen und Körperschaften:
|
Manor, M J (VerfasserIn); Piercey, S J (VerfasserIn) |
| Format: |
E-Artikel
|
| Sprache: |
English
|
| veröffentlicht: |
Natural Resources Canada, 2021 |
| Gesamtaufnahme: |
Targeted Geoscience Initiative (TGI-5)
Whole-rock lithogeochemistry, Nd-Hf isotopes, and in situ zircon geochemistry of VMS-related felsic rocks, Finlayson Lake VMS district, Yukon; Geological Survey of Canada
|
| Schlagwörter: |
Https://Geoscan.Nrcan.Gc.Ca/Starweb/Geoscan/Servlet.Starweb?Path=Geoscan/Shorte.Web&Search1=Project=340312;
|
| Quelle: |
GEOSCAN
|
| Zusammenfassung: |
The Finlayson Lake district in southeastern Yukon is composed of a Late Pal...
The Finlayson Lake district in southeastern Yukon is composed of a Late Paleozoic arc-backarc system that consists of metamorphosed volcanic, plutonic, and sedimentary rocks of the Yukon-Tanana and Slide Mountain terranes. These rocks host >40 Mt of polymetallic resources in numerous occurrences and styles of volcanogenic massive sulphide (VMS) mineralization. Geochemical and isotopic data from these rocks support previous interpretations that volcanism and plutonism occurred in arc-marginal arc (e.g., Fire Lake formation) and continental back-arc basin environments (e.g., Kudz Ze Kayah formation, Wind Lake formation, and Wolverine Lake group) where felsic magmatism formed from varying mixtures of crust- and mantle-derived material. The rocks have elevated high field strength element (HFSE) and rare earth element (REE) concentrations, and evolved to chondritic isotopic signatures, in VMS-proximal stratigraphy relative to VMS-barren assemblages. These geochemical features reflect the petrogenetic conditions that generated felsic rocks and likely played a role in the localization of VMS mineralization in the district. Preliminary in situ zircon chemistry supports these arguments with Th/U and Hf isotopic fingerprinting, where it is interpreted that the VMS-bearing lithofacies formed via crustal melting and mixing with increased juvenile, mafic magmatism; rocks that were less prospective have predominantly crustal signatures. These observations are consistent with the formation of VMS-related felsic rocks by basaltic underplating, crustal melting, and basalt-crustal melt mixing within an extensional setting. This work offers a unique perspective on magmatic petrogenesis that underscores the importance of integrating whole-rock with mineral-scale geochemistry in the characterization of VMS-related stratigraphy.
|
