Contact-style magmatic sulphide mineralisation in the Labrador Trough, northern Quebec, Canada: implications for regional prospectivity

• Main Authors: Smith, William Daniel, Maier, Wolfgang D., Bliss, Ian
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: NRC Research Press (a division of Canadian Science Publishing) 2019
• Subjects: Canada; montagnais
• Online Access: http://hdl.handle.net/1807/100281; http://www.nrcresearchpress.com/doi/abs/10.1139/cjes-2019-0137

The Labrador Trough in northern Qubec is currently the focus of ongoing exploration for magmatic Ni-Cu-PGE sulphide ores. This geological belt hosts voluminous basaltic sills and lavas of the Montagnais Sill Complex, which are locally emplaced amongst sulphidic metasedimentary country rocks. The recently discovered Idefix PGE-Cu prospect represents a stack of gabbroic sills that host stratiform patchy net-textured sulphides (0.2 to 0.4 g/t PGE + Au) over a thickness of ~ 20 m, for up to 7 km. In addition, globular sulphides occur at the base of the sill, adjacent to the metasedimentary floor rocks. Whole-rock and PGE geochemistry indicates that the sills share a common source and that the extracted magma underwent significant fractionation before emplacement in the upper crust. To develop the PGE-enriched ores, sulphide melt saturation was attained before final emplacement, peaking at R factors of ~ 10,000. Globular sulphides entrained along the base of the sill ingested crustally-derived arsenic and were ultimately preserved in the advancing chilled margin. The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author.