Mixing of brine with oil triggered sphalerite deposition at Pine Point, Northwest Territories, Canada

Author
Szmihelsky, Marko
Steele-MacInnis, Matthew
Bain, Wyatt M.
Falck, Hendrik
Adair, Robin
Campbell, Brandon
Dufrane, S. Andrew
Went, Ashley
Corlett, Hilary
Faculty Advisor
Date
2021
Keywords
oil , brine , sphalerite deposition , Northwest Territories , Canada
Abstract (summary)
Hydrocarbons are commonly invoked as triggers for the precipitation of sphalerite in carbonate-hosted Pb-Zn deposits, but direct evidence for the presence of petroleum during sulfide mineralization is rarely documented. Here, we report evidence of fluid mixing between basinal brines and oil during deposition of coarse sphalerite at a classic carbonate-hosted Pb-Zn district, Pine Point, Northwest Territories, Canada. The brines contain high concentrations of Pb, detectable aqueous sulfate, and hydrocarbons that attest to chemical interaction with oil. The oil inclusions in sphalerite contain much less Pb relative to the brines and no evident H2S, suggesting that the principal role of hydrocarbons was as a reductant. Mixing of brine with oil enabled the conversion of aqueous sulfate to sulfide, and thereby triggered sphalerite deposition.
Publication Information
Szmihelsky, M., Steele-MacInnis, M., Bain, W.M., Falck, H., Adair, R., Campbell, B., Dufrane, S.A., Went, A. and Corlett, H.J., 2021. Mixing of brine with oil triggered sphalerite deposition at Pine Point, Northwest Territories, Canada. Geology, 49(5), pp.488-492. https://doi.org/10.1130/G48259.1
DOI
Notes
Item Type
Article
Language
English
Rights
All Rights Reserved