AbstractsEarth & Environmental Science

This thesis deals with the general geology in the vicinity of Bralorne Mines, British Columbia. Late Palaezoic and Mesozoic sedimentary and volcanic rocks have been intruded by igneous masses genetically related to the Coast Range Batholith which has given rise to metalliferous deposits. The ore deposits of Bralorne Mines and Pioneer Mines are described particularly with regard to structural features. The vein bearing fissures of these deposits are, believed to be the result of compressive stresses originating southwest of the area. The ore shoots are believed due to various causes, among which the faulted and branched nature of the vein fissures are considered of prime importance. The presence of soda-rich rocks in the vicinity of the ore deposits is stressed, with the belief that such rocks have been developed by changing conditions in the differentiation of a normal magma stem. These conditions have given rise to the albite-rich diorite, the albite granite, related dykes, and subsequently the ore deposits themselves.