Jared Liimu's Honours Thesis Abstract

Thesis Title: 
The Role of Brittle-Ductile Deformation and Competency Contrast in Gold Mineralization in the C-Zone, Hemlo Gold Camp, Ontario
Jared J.

the Hemlo gold mine is located along the Hemlo shear zone within the Hemlo-Schreiber greenstone belt, within the Wawa subprovince of the Superior Province.  Geographically, the mine is located 350 km east of Thunder Bay, Ontario, Canada.  The C-zone has a mineralization style distinct from the well-studied B-zone.  Detailed mapping, oriented sampling, drill core observations, and a microstructural analysis were completed to determine the role brittle deformation plays in gold mineralization.  Ductile deformation of feldspar grains indicates amphibolite facies temperatures during deformation, consistent with historical work on metamorphism.  Annealed grains are evidence for lingering high temperatures.  The area is characterized by mutually overprinting brittle and ductile deformation within all lithological units.  The degree of deformation within each lithological unit indicates competency contrast during brittle-ductile deformation and the competency contrast plays a key role in the mineralization of gold in the C-zone at Hemlo.  Gold occurs within deformed quartz veins in more competent rock bodies.  Gold is also found along quartz veins within the less competent rock and within the more competent rock as fine-grained disseminated gold.