Petrographic and fluid inclusion studies on the Metalore-Golden highway deposit, Thunder Bay district, Ontario

Abstract

The gold-bearing Metalore shear zone and Golden Highway quartz-carbonate vein in the Beardmore-Geraldton Archean Greenstone Belt occur along the Paint Lake splay faults at the contact between metavolcanic rocks and metaconglomerates intruded by pre-ore diorite. The Metalore and Golden Highway deposits were emplaced during a late tectonic event. They consist primarily of quartz, clinochlore, ankerite, potassium feldspars, sericite, pyrite, argentite and chalcopyrite with native gold. The minerals have been deformed and are cut by at least three healed fractures by fluid inclusions. Gold typically occurs in recrystallized quartz. Microthermometric and Raman spectroscopy techniques were used to study fluid inclusions in quartz, calcite, ankerite, chlorites and potassium feldspars.