| Title | Mantle metal mobility: preliminary gold and platinum group element geochemical results |
| Download | Download (whole publication) |
| |
| Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
| Author | Lawley, C J M ;
Jackson, S E; Petts, D C; Savard, D; Pearson, D G; Zhang, S; Zagorevski, A; Kjarsgaard, B A |
| Source | Targeted Geoscience Initiative: 2018 report of activities; by Rogers, N (ed.); Geological Survey of Canada, Open File 8549, 2019 p. 43-48, https://doi.org/10.4095/313635  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 | 104J/12; 104J/13; 104K/09; 104K/10; 104K/11; 104K/12; 104K/13; 104K/14; 104K/15; 104K/16; 104N; 104O/04; 104O/05; 104O/12; 104O/13 |
| Area | Atlin |
| Lat/Long WENS | -133.7667 -131.7167 59.8167 58.6833 |
| Lat/Long WENS | -80.0000 -80.0000 48.5000 48.0000 |
| Subjects | economic geology; igneous and metamorphic petrology; geochemistry; mineralogy; mineral deposits; sulphide deposits; gold; nickel; mineral potential; mineral exploration; ore mineral genesis;
mineralization; ore controls; petrogenesis; mantle; ophiolites; alteration; serpentinization; whole rock analyses; mass spectrometer analysis; scanning electron microscope analyses; isotopic studies; petrographic analyses; ultramafic rocks;
chondrites; Canadian Cordillera; Cache Creek Terrane; Phanerozoic; Mesozoic; Triassic; Paleozoic; Permian; Precambrian; Proterozoic |
| Illustrations | location maps; geoscientific sketch maps; photomicrographs; geochemical plots |
| Program | Targeted Geoscience Initiative (TGI-5) Knowledge Management Coordination |
| Program | Targeted Geoscience Initiative (TGI-5) Gold ore systems - System Controls - Time and Space |
| Released | 2019 03 01 |
| Abstract | Mantle sulphides are rare but relatively important mineral phases that dominate the chalcophile and/or siderophile element budget of the silicate Earth. The macro- to micro-scale distribution of mantle
sulphides and their trace chalcophile and siderophile elements, however, remains poorly understood. Herein we present new laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) spot and element mapping results for an assemblage of
naturally occurring sulphide, alloy, and native metal minerals recovered from ophiolitic mantle peridotite and pyroxenite (Atlin, British Columbia). Sulphide (pentlandite, pyrrhotite, chalcopyrite), alloy (awaruite) and native metal (copper and iron)
phases are interstitial to variably serpentinized olivine and pyroxene relicts at the micro-scale. Pentlandite (±pyrrhotite) occurs with magmatic clinopyroxene and is typically replaced by awaruite and native iron, suggesting super-reduced conditions
during serpentinization and desulphidation of the low-temperature equilibrated mantle sulphide assemblage rather than the late addition of sulphide minerals during and/or after ophiolite emplacement. Element mapping results further suggest that gold,
platinum and other metals were remobilized during serpentinization. New whole-rock nickel sulphide fire-assay (NiS-FA) platinum group element (PGE) results for the same Atlin ultramafic suite, however, yield flat chondrite-normalized profiles that
scatter around the composition of the primitive mantle, suggesting that precious metal remobilization was limited to the micro-scale. Future work will focus on the paragenetic history of this ultramafic suite using a combination of whole-rock
ultratrace geochemistry and isotopic studies. |
| 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 | 313635 |
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