Crede, Lars1,2; Evans, Katy1; Rempel, Kirsten1,3, Weihua Liu4, Brugger, Joël5; Etschmann, Barbara5; Bourdet, Julian6, Reith, Frank7,*
1School of Earth and Planetary Sciences, Curtin University, Perth, Australia, 2Germany, 3McGill University, Montreal, Canada, 4CSIRO Mineral Resources, Clayton, Vic 3168, Australia, 5School of Earth, Atmosphere and the Environment, Monash University, Clayton, VIC 3800, Australia, 6CSIRO, ARRC, 26 Dick Perry Avenue, Kensington WA 6151, Australia, 7School of Biological Sciences,The University of Adelaide, Adelaide, South Australia, 5005, Australia.
* Passed away in 2019.
Gold can be associated with hydrocarbons in hydrothermal gold deposits, but the near-absence of experimental data on gold-hydrocarbon interactions at hydrothermal conditions prevents a quantitative interpretation of the significance of the observed textural relationships. We present the results of hydrothermal two phase experiments that investigate Au partitioning between aqueous and organic liquids, and a petrographic and synchrotron investigation of samples from the McLaughlin epithermal Au deposit, USA. Carbonaceous material from McLaughlin contains Au concentrations of up to 18 ppm. We conclude that remobilisation and/or transport of Au by hydrocarbon-rich liquids cannot be excluded.
Katy Evans is an Associate Professor at Curtin University. She uses thermodynamics, petrography, and geochemistry to investigate open systems, especially those involving redox transformations. Current projects include the formation of nickel deposits in the Fraser Zone, Western Australia, and effects of industrial emissions on rock art on the Burrup Penninsula.