McCoy-Cove Property, Lander County, Nevada-Exploration Update of a Consolidated District

摘要

The McCoy-Cove Property is located along the prolific Battle Mountain/Eureka gold trend in the Fish Creek Mountains, approximately 35 miles south of Battle Mountain, Lander County, Nevada. Echo Bay Mines, Ltd. conducted mining at McCoy-Cove from 1987 to 2001, producing 3.3 million ounces of gold and> 110 million ounces of silver from skarn, polymetallic sulfide veins, and Carlin-style carbonate replacement deposits. In 2003, Newmont acquired the mining claims and actively began closure reclamation while conducting very limited exploration drilling. Victoria Resources (US) Inc. (Victoria) entered into an exploration lease agreement with Newmont in 2006; subsequently in 2007, renewed exploration drilling northwest along the Cove anticline redefined Echo Bay's Beta Zone as the deeper Helen Zone. In June 2012, Premier Gold Mines USA (Premier) acquired the Victoria lease agreement at Cove and continued surface exploration drilling. Premier developed a different exploration philosophy, visualizing a stratabound mineralization host over a structural intersection "plunge tube" host. In September 2014, Premier finalized an agreement with Newmont to purchase 100% of the McCoy-Cove 31,000 acre land package. The mineralization at the Cove Project is hosted in Triassic carbonate and siliciclastic sedimentary rocks that define an overlap sequence deposited over the Late Permian Golconda Allochthon. Late Mesozoic compressive stresses formed NW-striking, low-amplitude, thrust-fault propagation folding and NS-, NNE-, and NW-striking, deep-seated, normal fault structures. Granodiorite was intruded to the south of the project area during the Jurassic. Renewed intrusive activity occurred in the Middle to Late Eocene, using the existing structural fabric to emplace the Brown Stock. Long-lived, pulsing, porphyry-style, igneous and coeval hydrothermal activity in the McCoy-Cove area gave rise to proximal economic gold skarns, gold/silver base metal veins, and more distal Carlin-style, disseminated, carbonate replacement gold deposits. Post-gold-mineralization igneous activity in the area includes Oligocene felsic welded ash-flow tuffs, culminating with more recent spatter cones localized over the basin-bounding range-front faults. Recent exploration drilling by Premier has led to discovery of the 2201 Zone that is hosted within the Dixie Valley conglomerate beneath the Cove pit. The 2201 Zone is similar to the polymetallic sulfide veins that produced gold and silver from the Cove pit. Gold, silver, and local base metals within the 2201 zone are hosted both in a stratabound sense within dolomitic sandstone interbeds as pyrite+sphalerite+galena± pyrrhotite and chalcopyrite and as high-grade polymetallic veins of quartz+visible gold(VG)+pyrite±sphalerite+galena+pyrrhotite+chalcopyrite and rare magnetite that crosscut both conglomerate and sandstone beds within the Dixie Valley conglomerate. The aforementioned sulfide veins are relatively continuous and appear to be hosted within imbricate thrust faults refracting upward from the Cove Thrust. With the acquisition of the McCoy-Cove gold/silver district, Premier now has a trifecta of known deposit types for which to explore within the district: skarn, distal disseminated polymetallic sulfide, and Carlin-style carbonate replacement. The potential for deeper porphyry-related deposit types can be anticipated as Premier consolidates and further understands the complexities of the district.