Stephen Tan, MSc
S. Tan1, S.M. Brueckner1, B. Lafrance1, J. Simmons1, D. Tinkham1, J.C. Ordóñez Calderón2, G. Long2
1Mineral Exploration Research Centre (MERC), Harquail School of Earth Sciences, Laurentian University, Sudbury, Ontario, Canada
2Kinross Gold Corporation, Toronto, Ontario, Canada
The Great Bear Project is a new world-class gold deposit (total resources of 6.6 Moz) in the Red Lake Greenstone Belt of the Archean Superior Craton. The deposit comprises three ore zones distributed between two domains, known colloquially as the Felsic Domain and Mafic Domain. The LP Zone, which is hosted by metavolcanic rocks of the Felsic Domain, consists of vein-related and disseminated gold and accounts for the largest fraction of gold mineralization at the Great Bear deposit. The Hinge and Limb zones are smaller ore zones located within a property scale fold in the Mafic Domain. These zones are defined by gold-bearing quartz veins that are hosted by mafic metavolcanic rocks and sulfide rich argillite beds. The metavolcanic rocks of the Mafic Domain include high Fe and Mg tholeiitic mafic volcanic rocks, ultramafic flows, rhyolitic tuffs and flows. Thin argillite beds and iron formation commonly define the contact between Fe and Mg tholeiites and are intercalated within the Fe tholeiites. Existing age constraints for metavolcanic rocks of the Felsic Domain indicate emplacement at ca. 2710 Ma, but its stratigraphic relationship with Mafic Domain remains unclear. We hypothesize that the Mafic Domain is either an older basement component that predates the emplacement of the Felsic Domain rocks or a lower stratigraphic component within a continuous Neoarchean volcanic-sedimentary succession that includes the Felsic Domain. This research project aims to: (1) Characterize the mafic metavolcanic and metasedimentary rock of the Mafic Domain; (2) Determine the stratigraphy of the Mafic Domain in relation to the Felsic Domain; (3) Provide absolute and relative age constraints on the deposition of the Mafic Domain rocks.