| Title | Fluid inclusion LA-ICP-MS and whole rock geochemical investigation of possible magmatic contributions to the giant Windy Craggy Besshi-type VMS deposit |
| Download | Download (whole publication) |
| |
| Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
| Author | Schmidt, M A; Leybourne, M I; Peter, J M ; Petts, D; Layton-Matthews,
D |
| Source | Targeted Geoscience Initiative: 2018 report of activities; by Rogers, N (ed.); Geological Survey of Canada, Open File 8549, 2019 p. 189-204, https://doi.org/10.4095/313651  Open Access |
| Year | 2019 |
| Publisher | Natural Resources Canada |
| Document | open file |
| Lang. | English |
| Media | on-line; digital |
| Related | This publication is contained in Targeted Geoscience
Initiative: 2018 report of activities |
| File format | pdf |
| Province | British Columbia |
| NTS | 114P/02 |
| Area | Windy Craggy Mountain |
| Lat/Long WENS | -137.7833 -137.7461 59.7375 59.7208 |
| Subjects | economic geology; geochemistry; tectonics; mineral deposits; base metals; copper; cobalt; gold; sulphide deposits; volcanogenic deposits; mineral exploration; ore mineral genesis; mineralization; ore
controls; fluid dynamics; fluid inclusions; salinity; whole rock analyses; bulk composition; geochemical analyses; mass spectrometer analysis; trace element analyses; major element analyses; total dissolved solids; host rocks; bedrock geology;
lithology; igneous rocks; volcanic rocks; mafic volcanic rocks; basalts; andesites; sedimentary rocks; argillites; structural features; faults; tectonic history; magmatism; hydrothermal systems; alteration; Upper Triassic; analytical methods;
isotopic studies; lead isotope ratios; Windy Craggy Deposit; Tats Volcanic Complex; Alexander Terrane; Canadian Cordillera; Saint Elias Subterrane; Admiralty Subterrane; Craig Subterrane; Methodology; Phanerozoic; Mesozoic; Triassic |
| Illustrations | geoscientific sketch maps; tables; histograms; geochemical plots; plots |
| Program | Targeted Geoscience Initiative (TGI-5) Knowledge Management Coordination |
| Program | Targeted Geoscience Initiative (TGI-5) Volcanogenic massive sulphide ore systems - base metal sources and processes |
| Released | 2019 03 01 |
| Abstract | The world-class Windy Craggy Cu-Co-Au deposit, northwestern British Columbia, is investigated to assess potential magmatic contributions to mineralizing fluids in volcanogenic massive sulphide (VMS)
deposits. Windy Craggy is of particular interest for two reasons: 1) its atypically large size and high-grade; and 2) the observation of fluid inclusions with anomalously high salinities. The deposit has recorded fluids with salinities up to 17
weight % equivalent NaCl (most 6-16 weight % equivalent). The Ca/Na values in fluid inclusions determined by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) are greater than seawater and similar to values from other
mafic-dominated VMS systems. The fluid inclusions have variable metal and metalloid concentrations, with positive correlations between Cu, Mn, Zn, Sb, Sn and Bi. Also analyzed are Windy Craggy host lithologies, including footwall argillites,
relatively fresh to highly altered footwall mafic volcanic rocks and stringer and massive sulphides. These inclusions show similar trends and overlap the host rocks in Fe versus Mn and Cu versus Zn, but show clear excesses over host rocks in
antimony, tin, bismuth and similar elements that are commonly ascribed as indicative of magmatic input. We suggest that these excess values strongly point to direct magmatic contributions to the Windy Craggy ore-forming fluids, as opposed to simply
reflecting leaching of metals from the footwall sedimentary and igneous rocks. |
| Summary | (Plain Language Summary, not published)
The Targeted Geoscience Initiative (TGI) is directed towards providing next generation knowledge and methods to facilitate more effective targeting of
buried mineral deposits. The program aims to enhance the effectiveness of exploration for Canada's major mineral systems by resolving foundational geoscience problems that constrain the geological processes responsible for the liberation metals from
their source region, transportation of these ore metals and control their eventual deposition. TGI supports projects on gold, Ni-Cr-PGE, porphyry-style mineralization, uranium and volcanic- and sedimentary-hosted base metal mineralization ore
systems, with each project divided into subprojects focused on resolving specific knowledge gaps by integrating data and studies from multiple sites across Canada. Herein, we present interim results and interpretations from a selection of the
research activities currently being conducted under the auspices of TGI. |
| GEOSCAN ID | 313651 |
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