Version 1
: Received: 7 September 2018 / Approved: 10 September 2018 / Online: 10 September 2018 (05:53:04 CEST)
How to cite:
Marshall, D.; Nicol, C.; Greene, R.; Sawyer, R.; Stansell, A.; Easterbrook, R. Precious Metal Enrichment at the Myra Falls VMS Deposit, British Columbia, Canada. Preprints2018, 2018090151. https://doi.org/10.20944/preprints201809.0151.v1
Marshall, D.; Nicol, C.; Greene, R.; Sawyer, R.; Stansell, A.; Easterbrook, R. Precious Metal Enrichment at the Myra Falls VMS Deposit, British Columbia, Canada. Preprints 2018, 2018090151. https://doi.org/10.20944/preprints201809.0151.v1
Marshall, D.; Nicol, C.; Greene, R.; Sawyer, R.; Stansell, A.; Easterbrook, R. Precious Metal Enrichment at the Myra Falls VMS Deposit, British Columbia, Canada. Preprints2018, 2018090151. https://doi.org/10.20944/preprints201809.0151.v1
APA Style
Marshall, D., Nicol, C., Greene, R., Sawyer, R., Stansell, A., & Easterbrook, R. (2018). Precious Metal Enrichment at the Myra Falls VMS Deposit, British Columbia, Canada. Preprints. https://doi.org/10.20944/preprints201809.0151.v1
Chicago/Turabian Style
Marshall, D., Armond Stansell and Ross Easterbrook. 2018 "Precious Metal Enrichment at the Myra Falls VMS Deposit, British Columbia, Canada" Preprints. https://doi.org/10.20944/preprints201809.0151.v1
Abstract
Gold, present as electrum, in the Battle Gap, Ridge North-West, HW, and Price deposits at the Myra Falls mine, occurs in late veinlets cutting the earlier VMS lithologies. The ore mineral assemblage containing the electrum comprises dominantly galena, tennantite, bornite, sphalerite, chalcopyrite, pyrite and rare stromeyerite is defined as an Au-Zn-Pb-As-Sb association. The gangue is comprised of barite, quartz, and minor feldspathic volcanogenic sedimentary rocks and clay. Deposition of gold as electrum in the baritic upper portions of the sulphide lenses occurs at relatively shallow water depths beneath the sea floor. Primary, pseudosecondary, and secondary fluid inclusions, petrographically related to gold, show boiling fluid inclusion assemblages in the range of 123 to 173 °C, with compositions and eutectic melt temperatures consistent with seawater at approximately 3.2 wt% NaCl equivalent. The fluid inclusion homogenization temperatures are consistent with boiling seawater corresponding to water depths ranging from 15 to 125 metres. Slightly more dilute brines corresponding to salinities of approximately 1 wt% NaCl indicate that there is input from very low-salinity brines, which could represent a transition from subaqueous VMS to epithermal-like conditions for precious metal enrichment, mixing with re‑condensed vapour, or very low-salinity igneous fluids.
Keywords
VMS deposits; gold; fluid inclusions
Subject
Environmental and Earth Sciences, Geochemistry and Petrology
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
