This project will focus on fluid evolution in the upper part of the hydrothermal system at the Archean Wiluna lode-gold deposits. The mixing of surface and deep-seated ore fluids may be an important precipitation mechanism for gold and other metals. The goal of this study is to constrain surface water components in the Wiluna deposits, and to quantify fluid fluxes in the metasomatic zones. This will be the first to study the nature and role of surface waters in Archean lode-gold systems. The surface water components of the fossil hydrothermal system will be quantified by GC/IC, PIXE-probe, and noble gas analyses on fluid inclusions, and stable isotope analyses on homogeneous groups of fluid inclusions and alteration minerals. Mass- transfer modeling will quantify fluid flow through channel ways and wallrock, and will quantify fluid mixing as a gold precipitation mechanism in the upper parts of the lodes. This research will be conducted in collaboration with the Key Centre for Strategic Mineral Deposits, Perth and the Bureau of Mineral Resources, Canberra.
