Electronic Thesis and Dissertation Repository


Master of Science




Dr. Robert Linnen


Cu-PGE mineralization at the Geordie Lake Deposit (GLD) is spatially associated with weak to intense actinolite and albite alteration within gabbro and troctolite. Previous studies have determined a magmatic, and magmatic-hydrothermal origin of the deposit. The most significant Cu-PGE occurrence in the GLD is dominantly stratiform, and in contact with a basal syenite. Similar patterns of REE with progressive enrichment from troctolite, to gabbro, and basal syenite indicate that these lithologies are genetically linked. Major element geochemistry shows no discernable variation between the altered and unaltered samples. Whole rock δ18O analyses were conducted in equal intervals down the stratigraphy of the GLD revealing asteady depletion in δ18O from 5.1‰ at the surface of the deposit, to 1.3 ‰ at the basal contact with cross-cutting syenite. The results show that sulfide deposition is magmatic, though interaction with late stage magmatic fluid redistributed some sulfide components.