The projects were a joint venture with
Atna had the option of earning a 51% interest in the properties by spending $5 million on exploration over five years. The properties comprise a 17,700-acre land package 60 miles south of Fairbanks. Geologically, the properties are underlain by Paleozoic-aged sedimentary rocks of the Yukon-Tanana Terrane.
The Dry Creek property hosts two zones of volcanogenic massive sulphide (VMS) mineralization. These occur on the northern and southern limbs of an east-westerly trending synclinal fold.
Previously, Grayd explored the central portion of the DC North horizon, testing two en echelon zones of mineralization: Discovery and Foster. Based on 38 holes, the DC North horizon was estimated to have an inferred resource of 2.9 million tonnes grading 4.4% zinc, 1.9% lead and 0.2% copper, plus 93.6 grams silver and 0.55 grams gold per tonne. Most of the resource is in the Foster Creek zone, which is hosted by pyritic sediments, and the Discovery zone, which is hosted by altered rhyolite.
The northern limb of the Dry Creek syncline dips gently to the south and hosts the WTF zone. In the early 1980s, exploration at Dry Creek focused on the WTF zone, where drilling delineated a resource of 3.1 million tonnes grading 6% zinc, 2.5% lead, 6.7 oz. silver and 0.03 oz. gold. The thickness of this narrow zone of mineralization ranges between 0.3 and 5 metres.
At the Anderson Mountain property, 18 miles southwest of Dry Creek, VMS-style mineralization can be found in Devonian-to-Mississippian felsic volcanics and sediments.
Searching for a thick intersection that would indicate a large deposit, Atna tested the DC North zone with 12 holes over a 13,500-ft. strike length and up to 1,000 ft. downdip, while two additional holes tested a large alteration zone to the south.
Holes 62, 66, 67, 68 and 69 tested the Discovery zone along strike, east of the previous drilling and downdip. All the holes intersected disseminated sulphide mineralization, with hole 69 cutting 25 ft. grading 1.4% zinc, 0.34% lead and 0.39 oz. silver in the Foster zone and 14 ft. of 2.5% zinc, 0.55% lead and 0.13 oz. silver in the Discovery zone. Hole 62 hit 11.5 ft. grading 2.3% zinc, 0.71% lead and 4.62 oz. silver in the Foster zone and was stopped short of the Discovery zone, owing to bad ground conditions. Hole 66 was collared 1,000 ft. west of hole 62 and hit 56 ft. of 2.07% zinc, 0.77% lead and 0.13 oz. silver. Holes 67 and 68 were collared 2,000 ft. and 4,500 ft. east of hole 62, respectively, and failed to hit any significant mineralization.
Holes 65, 70 and 71 were collared 2,500 ft. west of the Foster zone. Hole 65 intersected 6 ft. of massive sulphides, with assay results pending. Hole 70 and hole 71 both failed to intersect significant mineralization.
Hole 73 was collared 3,000 ft. west of hole 65 and hit 1.5 ft. averaging 2.4% zinc, 0.74% lead and 3.6 oz. silver. Holes 63 and 64 tested the downdip extension of the Foster zone, where previous drilling hit 160 ft. grading 4.2% zinc. Hole 63 was stopped prematurely because of broken ground, whereas hole 64 hit 81 ft. of weak mineralization. Assay results are pending.
Two holes, 74 and 75, tested a highly altered area south of the DC North horizon. Both holes intersected quartz-sericite-pyrite alteration. Hole 74 cut a 3-ft. intersection grading 2.4% zinc, 1.7% lead and 0.22 oz. silver.
The drill program failed to meet Atna’s required objectives for outlining a large deposit.
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