A Petrographic and Fluid Inclusion Comparison of mid-Cretaceous gold bearing veins near the 5 Moz Coffee Deposit, west-central Yukon ...

• Main Author: Lee, Well-Shen
• Format: Text
• Language: English
• Published: The University of British Columbia 2017
• Subjects: Dawson; Yukon
• Online Access: https://dx.doi.org/10.14288/1.0347626; https://doi.library.ubc.ca/10.14288/1.0347626

The Dawson Range district in west-central Yukon is host to various important mineral deposits, including several fault and fracture-hosted gold systems, such as the significant 5 Moz Coffee gold deposit. Three gold-bearing hydrothermal vein systems of inferred mid-Cretaceous age (~92-96 ma), sharing the same Au-As-Sb relationship as Coffee are located nearby. A field, petrographic and microthermometric investigation concludes that the Boulevard and Sugar prospects share a common auriferous vein generation with similar ore and gangue minerals. Auriferous veins are strongly controlled by steeply dipping, brittle shear-structures with cataclasite zones as well as disseminated gold-hosting arsenian pyrite replacing mafic minerals and magnetite within the host rock- features also observed at Coffee. Boulevard, Sugar and Longline (a past-producer of gold in the Dawson Range) share similar low salinity (0-8 wt% NaCl), CO₂ rich (~0.22 mol%), methane bearing fluids, suggesting a possible co-genetic relationship. All ...