Work History

Silver Standard Mines Ltd. staked YU cl (73506) in July 1958 and explored with mapping and EM surveys in 1958-1959.

Re-staked by G. Dickson as Wedge cl 1-15 (YA82167), by M. Muursepp as Bull cl 1-8 (YA81420) and other miscellaneous claims, in 1984. Prochem Ltd. optioned the leased claims and some of the Wedge claims and explored with soil geochemistry, prospecting, EM-16 surveys and bulldozer trenching in 1985; grid geochemistry, trenching, mapping and EM geophysics in 1986; and bedrock mapping and ground magnetics in 1988. The 1987 and 1988 work was funded by a subsidiary of Prochem's; Aurchem Resources Ltd.

Aurchem added JBF cl 1-7 ((fractional) YB362590) and Jon-Wedge cl 1-6 (YB35895) in August 1992 and explored with 3,384.8 m of reverse circulation drilling in 32 holes in July and August, 1992. In July 1993, the Wedge cl 1-4 and 16-17 were transferred to J. Dickson from the estate of G. Dickson. In 1993, Aurchem conducted soil geochemistry on the claims covering the Transition occurrence.

In March 1995, the Wedge claims were transferred to Aurchem Exploration Ltd. In early 1996, BYG obtained an option to purchase all of Aurchem's claims located in the Mt Nansen area. As part of this agreement BYG funded an extensive trenching and mapping program from August to October 1996, on the Bull 2, JBF 1-f, Jon-Wedge 3 and LCGS 1 claims. BYG encountered financial difficulties at the end of 1996 and suspended most exploration activities. In February 1999, BYG announced plans to temporarily shut down the Mount Nansen Mine. In March 1999, BYGwas placed in receivership and the Nansen mine became a Type II Minesite. The Wedge, Etzel and Bull claims reverted to Aurchem after the federal government took over maintenance of the adjoining Mount Nansen mine site in July 1999.

In 2009, 101073531 Saskatchewan Corp. flew a regional airborne and magnetic survey that included the Transition occurrence. In 2011, Ansell Capital Corp optioned the Discovery Creek property, including the Transition occurrence, from Aurchem Exploration. Ansell Capital carried out bedrock mapping as well as rock and soil geochemistry in 2011.

Regional & Property Geology

The occurrence is located in the Dawson Range within Yukon-Tanana Terrane (YTT). The rocks of the YTT in this region consist of Early Mississipian metamorphic rocks separated into meta-sedimentary and meta-igneous suites (Stroshein, 1998). The meta-sedimentary suite consists of micaceous quartz-feldspar gneiss, schist and quartzite of the Nasina Assemblage. The meta-igneous package is comprised of biotite-hornblende feldspar gneiss and coarse-grained granodiorite orthogneiss with lesser amphibolite.

Four rock types dominate the geology surrounding the occurrence and are comprised of:
1. Paleozoic metamorphic Yukon-Tanana gneiss, quartzite, and amphibolite to the south;
2. Triassic to Jurassic metamorphosed alkali-feldspar-rich plutonic suites;
3. Mid-Cretaceous Mount Nansen Suite andesite, felsic lapilli tuffs, basaltic to latite volcanic rocks; and quartz feldspar porphyry, dacite, latite, and quartz monzonite porphyritic hypabyssal rocks; and
4. Mid-Cretaceous Whitehorse granodiorite.

A porphyry copper-molybdenum complex (MINFILE occurrence 115I 066) is found in the northeast section of the property, with argillic and propylitic alteration haloes covering the remainder. The porphyry complex occurs at the intersection between a major northwest structure and an east-west fault. Copper and molybdenum ± gold and silver occur in a porphyry stock and phyllic-altered granodiorite. Surface leaching and oxidation is variable, but can reach considerable depths. A steeply dipping, northwest-striking epithermal vein system which formed peripheral to the porphyry migrated inward during cooling and collapsed, creating a complex system of overlapping mineralization including: porphyry Cu-Mo-Au-Ag; northwest striking mesothermal quartz-pyrite-gold veins; and northwest striking epithermal quartz-Au-Ag-Pb-Zn-Cu veins.

Mineralization & Results

The Transition occurrence consists of four main quartz-pyrite-gold veins and stockworks hosted in granodiorite within the phyllic alteration zone of the porphyry complex, as well as gold-silver-lead-copper veins and stockwork overprinted on earlier porphyry mineralization and alteration. Porphyry-related quartz and quartz-tourmaline breccias are found within a general argillic alteration zone.

RC drilling at Transition in 1988 returned elevated assay values of up to 0.014 oz/ton Au, 0.029 oz/ton Ag, 448 ppm Pb, 747 ppm Zn, and 1534 ppm As over 5 feet, as well as 0.61 oz/ton Au, 1.28 oz/ton Ag, 1108 ppm Zn and 0.21% As over 5 feet. 

Assessment Reports that overlap occurrence