- 100% owned by ATAC
- Early stage porphyry target located 14 km east of Western Copper and Gold's Casino copper-gold project
- Limited drilling and airborne radiometric data indicate the potential for a high-level porphyry system
- None of the historic drill holes were drilled deep enough to test the main IP anomalies
Idaho Creek Geology
The metallogeny in the Dawson Range is dominated by porphyry and mesothermal vein deposits. Idaho Creek lies 14 km east of the Casino porphyry gold-copper-molybdenum deposit. The Coffee gold project is located further to the northwest of Idaho Creek while gold-silver veins that hosted the former Mt Nansen mine and Rockhaven Resources' Klaza Project are situated to the southeast. The property sits within the Klotassin Batholith. It is bounded to the west by the northeast-trending Dip Creek Fault and to the north by a southeast-trending fault that is inferred to be the northerly extension of the Big Creek Fault. The Big Creek Fault typically exhibits two or more sub parallel structures that are the bounding faults of a two to eight kilometre wide graben. A belt of precious metal bearing veins and porphyry copper-gold prospects, associated with Cretaceous age, subvolcanic quartz-feldspar porphyry intrusions, extends southeasterly from the Coffee project for 120 km along the Big Creek Fault.
Idaho Creek Mineralization
Previous grid soil geochemistry outlined anomalous gold, silver, lead, arsenic and zinc soil values in four main targets across the property, all apparently associated with one or both of two main structural trends related to the Big Creek Fault. The anomalous areas are up to 1,200 by 600 m in size and produced soil geochemical values ranging up to 6,550 ppb Au, 122 ppm Ag, 6,180 ppm Pb, 2,620 ppm As, 2,300 ppm Zn and 1,110 ppm Sb. The average silver to lead ratio for the samples is a particularity encouraging 366 grams /tonne silver per 1% lead.
The soil geochemical anomalies are largely unexplained.A total of nine bulldozer trenches with a combined length of 2,398 m were excavated within the main soil geochemical anomalies in the 1980's. The trenches mostly bottomed in frozen soil and exposed only small patches of bedrock. Three types of mineralization identified in trenches or in outcrops include: disseminated sulphides in quartz diorite; chalcedony-calcite veins in limonitic quartz-feldspar porphyry; and sulphide-bearing manganiferous quartz veins.
Exploration renewed in 2006, consisting of 17 line km of induced polarization (IP) surveys and 556 m of reverse circulation drilling. Five percussion drill holes tested beneath float occurrences and soil geochemical anomalies in the western and central part of the property. Collar locations were based solely upon prospecting and geochemical data because IP results were not available prior to drilling.
Anomalous gold and silver values were encountered in most holes. The results from holes ID-06-03 and -05, which tested downdip from geochemical anomalies that overly the main IP target, are particularly interesting. ID-06-03 is near a narrow, moderate chargeability anomaly that appears to be near the top of the main anomaly. It encountered two mineralized intervals, with the first returning 0.608 g/t gold and 20.6 g/t silver across 6.10 m starting at 9.14 m and the second yielding 0.551 g/t gold, 32.6 g/t silver, 0.46 % lead and 1.53 % zinc across 3.05 m starting at 73.15 m. ID-06-05 produced two 3.05 m intervals grading 0.33 g/t gold with 70.1 g/t silver and 0.092 g/t gold with 52.3 g/t silver. These intervals were cut from 36.58 and 60.96 m, respectively. None of the holes were drilled deep enough to test the main IP anomalies.
The metal signature of the soil geochemical anomalies and percussion drill results combined with geological setting and airborne radiometric data are indicative of a high level porphyry system. The mineralization exposed at surface and found in drill holes may be related to stockwork fracture zones that overlie a deeper porphyry copper-gold deposit.