Faults and fluid-rock reaction: controls on the massive Carlin-type gold deposits of Nevada

The Carlin-type gold deposits of Nevada represent one of the greatest gold concentrations on Earth. The deposits are hosted within limestones and dolomites of the Great Basin in Nevada. While the deposits are huge, and formed from large volumes of fluids, those fluids have left only cryptic signatures of their passage and interaction with their host rocks. In this presentation, I will present two case studies, one at the microscale (on auriferous pyrite), one at the kilometre scale (utilising large oxygen isotope data sets), which provide information on how faults controlled hydrothermal fluid flow, and how fluid-rock reaction caused the precipitation of gold-rich pyrite. Finally, I’ll present emerging “clumped” stable isotope data, which will allow us to place new constraints on processes within carbonate-hosted hydrothermal systems in the future.