Geology, hydrothermal activity and gold mineralization in the Gemmell Lake area of the Early Proterozoic, Lynn Lake greenstone belt, Manitoba.

Gold mineralization in the Finlay McKinlay shear zone occurs in the second of two vein sets. These veins are characterized by vein breccia, vein ribbons and secondary veinlets. Four stages of veinlets have been recognized. In order of formation, these are: (1) epidote-clinozoisite-magnetite; (2) pyrite-chalcopyrite-pyrrhotite; (3) native gold-galena-pyrite-chalcopyrite-galena-hessite-tellurobismuth and (4) sphalerite-covellite. Fluid inclusion data indicate that four types of fluids infiltrated the Finlay McKinlay shear zone. These are: (1) low density aqueous vapours; (2) moderate to low salinity aqueous fluids; (3) low salinity, H$\sb2$O-CO$\sb2$ fluids with minor CH$\sb4$ and N$\sb2$ ($\u3c$12 mole % CH$\sb4$.) and (4) a high salinity, aqueous fluid, (29 to 30 wt % NaCl + CaCl$\sb2$ equiv.). Gold mineralization occurs in veinlets in vein set 2 quartz. The lowest salinity aqueous fluids appear to be the mineralizing fluids. (Abstract shortened by UMI.)Dept. of Geology and Geological Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1992 .S455. Source: Masters Abstracts International, Volume: 31-03, page: 1176. Adviser: Iain M. Samson. Thesis (M.Sc.)--University of Windsor (Canada), 1992