Rau Project
Location
The Rau Project is located 55 km northeast of Keno City in Central Yukon. The project is over 1300 sq km and is situated between the regional-scale Dawson thrust and Kathleen Lakes fault, within a Paleozoic carbonate inlier of the Selwyn Basin tectonic province. Replacement-style, gold-bearing sulphide and oxide mineralization occurs in Bouvette Formation shallow water limestone, dolomite, and calcareous siltstone of Cambrian to Devonian age. ATAC Resources Ltd. wholly owns the project, which was a grass roots discovery in 2006. Since then, it has acquired by staking over 160 km of potential strike length of favourable structure and stratigraphy, of which only a very small portion has been explored for gold.
Exploration conducted by ATAC has focused along a 15 km portion of the Bouvette Formation where it forms a local ridge system bound by the Beaver and Rackla Rivers. Carbonate strata at the southeast end of the ridge system is intruded by a small early Tertiary (62.9+0.5 Ma) granite stock. Work along the 15 km trend comprises widely spaced soil geochemical surveys, airborne VTEM surveys plus limited geological mapping and prospecting. Detailed work conducted in a 3 km by 5 km area at the southeastern end of this trend focused on the Tiger Zone and included detailed grid soil geochemical surveys and diamond drilling of 71 holes.
The Tiger Zone is a stratigraphically-controlled gold deposit that trends northwest and dips moderately northeast and is characterized by replacement of host carbonates. It is currently 650 m long, 100 to 200 m wide, and up to 96 m thick. Mineralization is contained within a 40 m to 150 m wide zone of small-scale folding and shearing, which is itself developed in and adjacent to a regionally extensive corridor of highly strained rocks. The mineralized system is defined by a series of stacked and folded limestone horizons intercalated with locally extensive mafic flows and volcaniclastic units. Most of the exploration has been directed toward the Discovery Horizon, although there is evidence for at least two additional stratabound intervals of gold mineralization.
Gold occurs in both sulphideand oxide material. Sulphide mineralization is accompanied by, and developed within, limestone which is replaced by ferruginous dolomite and iron carbonate minerals. Sulphide species consist of disseminated to banded pyrite, with subordinate arsenopyrite and pyrrhotite, and minor bismuthinite and sphalerite. Small amounts of disseminated scheelite are also present. The main sulphide minerals exhibit at least three stages of mineralization. The best intersection from sulphide-bearing mineralization averaged 4.04 g/t gold over 96.01 m from hole Rau-09-66.
Oxide mineralization is completely devoid of sulphide minerals and ranges from very competent, weakly porous limonitic mud to rubbly porous limonitic grit. The oxide appears texturally amorphous in most intersections but occasionally exhibits residual color banding that may represent relict sulphide textures. Complete oxidation extends up to 150 m from surface. The best oxide grades (e.g., hole Rau-09-19, which assayed 24.07 g/t gold across 28.04 m) and deepest oxidation occur where north-striking extensional faults intersect the regional northwest-striking structure. The nature of the contacts between the oxide and sulphide facies is poorly understood, as is the gold distribution in the mineralized horizon and within individual sulphide species. Mineralization at the Tiger Zone remains open along strike and down dip, as well as at depth across a normal fault that locally defines the southwest margin of the favourable structural corridor.
Preliminary metallurgical test results on gold-bearing oxide material are very encouraging and demonstrate that the oxide mineralization is potentially amenable to conventional cyanide extraction processes. Additional tests are underway to assess the metallurgy of sulphide material.
In addition to the work done at the Tiger Zone, ATAC identified six new surface gold zones by following up high values from grid and widely spaced reconnaissance soil sampling. The best zones are in a 500 m wide belt, which lies 2 to 5 km along strike to the northwest of the Tiger Zone, in and adjacent to the northwest-striking structural corridor. Anomalous soil geochemical values stretch intermittently for about 22 km to the northwest along the projected trace of the structural corridor, which is marked by electromagnetic conductors. Surface rock samples collected from talus or recessively weathered areas assayed between 1.0 and 18.5 g/t gold.
An aggressive $12.5 million program of mapping, geochemical sampling, and diamond drilling involving at least four drills is underway for the Tiger Zone area in 2010, as well as systematic first pass exploration of the rest of the property.
History
Land & Purchase Agreement
Geology
Mineralization
Resource Estimates
First Nations/Environmental
Work Programs (past and present)