Pine Point Property
The Pine Point property is located on the eastern flank of the Western Canada Sedimentary Basin in the southern Northwest Territories near the southern shore of Great Slave Lake. It occurs in a mid-Devonian carbonate barrier complex called the Presqu'ile barrier.
Subtle tectonic adjustments along three northeast-trending hinge lines contributed to the evolution of numerous paleoenvironmental facies within and adjacent to the barrier complex. The hinge lines are approximate projections of the underlying Precambrian McDonald-Great Slave Lake fault system. They are all lines of weakness in the bedrock where preferential Karstification, coarse-grained dolomite alteration (replacement and cement) and sulphide mineralization are concentrated (Hannigan, n.d).
Recent advances in understanding large-scale fluid flow in the crust and in sedimentary basins establishes that most Mississippi Valley Type (MVT) districts are the product of regional or subcontinental-scale hydrological movements. The MVT deposits were formed by warm saline aqueous solutions similar to oil field brines that migrated in sedimentary basins through aquifers in platform-carbonate sequences toward the basin peripheries (Hannigan, n.d).
The R190 deposit is the subject of Tamerlane's Pine Point Project. The delineated deposit has NI 43-101 compliant Proven and Probable Reserves of 1 million tonnes at a grade of 10.98% zinc and 5.28% lead. In addition to the 2P Reserves, R190 has 1.6 million tonnes of NI 43-101 compliant Measured and Indicated Resources grading 2.72% zinc and 1.37% lead and 0.3 million tonnes of Inferred Resources grading 2.86% zinc and 1.08% lead. The deposit was modeled utilizing data from 60 holes historically drilled by Westmin and 13 holes drilled by Tamerlane during their 2005 (10 holes) and 2008 (3 holes) exploration programs.
The R190 deposit lies within the main trend of the Pine Point mineralized trends. Overburden thicknesses encountered during Tamerlane's drill programs ranged from 85 to 147 feet. No outcrop exposures were seen in the area of the deposit during the drill campaigns. The ore body is a prismatic type occurring in a karst which bottoms just above sandy dolomite in the Pine Point Formation and continues up through the Watt Mountain into the Slave Point Formation.
Ore mineralization consists of galena and sphalerite. Tamerlane's drilling programs indicated that ore grades vary from sub-economic levels on the fringes of the prismatic ore body to as high as 52.06% combined zinc and lead over 32.5 feet thickness in drill hole R190-TV5. Mineralization of over 2% combined zinc and lead in the drilling program occurred over thicknesses ranging from a minimum of 60.5 feet in hole TV05 to a maximum of 170 feet in hole R190-08-TV13.
Zinc and lead occur as fine crystals on the rims of vugs or within calcite +/- dolomite in thin veinlets on the margins of the ore body. Zinc and lead increase in abundance towards the center of the deposit filling vugs and larger veins, and occurring in massive mineralized zones consisting of skeletal to massive galena and coliform sphalerite common.
Sulfur and bitumen commonly occur in vugs, veins, and pore spaces in and around the zinc-lead mineralization. Pyrite +/- marcasite occur as disseminations within the massive ore sequence to massive horizons near the base and below the zinc-lead mineralization. Gypsum needles and their casts are common as are celestite seams or veins in association with the mineralized horizons.
Figure modified after Rhodes et. al. 1984
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