Geochemical data from samples collected in 2020 and 2021 for the Western Tanacross project, Tanacross Quadrangle, Alaska

During the 2021 field season, geologists from the Alaska Division of Geological & Geophysical Surveys (DGGS) conducted 1:100,000-scale bedrock geologic mapping of ~2600 mi2 (~6900 km2) within the Tanacross and Eagle quadrangles. The field areas for the Western Tanacross project are approximately 20 miles north and southwest of Tok. Prospects in the region include Stibnite Creek, Tushtena, Taurus, and others. Much of the field area was mapped at 1:250,000 scale by the U.S. Geological Survey (USGS) in the 1960s (Foster, 1970). This project aims to produce more detailed and modern geologic maps and supporting datasets that will promote mineral resource exploration in eastern interior Alaska. Highlights of this DGGS western Tanacross geochemical report include precise location and sampling of the Discovery Zone, Dave's Zone, Eagle, Mosquito, North Mosquito Flats, Peternie, North Peternie, Bush, Sixtymile Butte, and VABM West prospects. Discovery Zone samples returned the highest Au values: 21ET178-4.94 ppm Au; 21ET179-2.86 ppm Au, with arsenic (As) of 42,500 ppm and 21,900 ppm, respectively. Sample 21ET178 has also elevated silver (Ag) at 14.35 ppm. Three samples from Dave's Zone returned over 1 ppm Au values: 21ET170-1.77 ppm; 21ET171-1.51 ppm; and 21ET164-1.03 ppm. Similar to the Discovery zone, those samples have high As: 9,690 ppm, 7,880 ppm, and 3,110 ppm, respectively. Sample 21ET171 has over 27 ppm of Ag. An amphibolite sample from the southern part of the Western Tanacross project, just east from Robertson River has 0.015 ppm of palladium (Pd) accompanied by 0.0027 ppm of platinum (Pt). The DGGS map area includes a section of pre-Mississippian to Permian metasedimentary and metaigneous rocks as well as Triassic to Paleogene intrusive and volcanic rocks. The analytical data tables associated with this report are available through the Alaska Geochemistry database (https://maps.dggs.alaska.gov/geochem). For a direct link to this data release, see http://doi.org/10.14509/30844.

Tags: analyses, analyses and sampling, analytical lab results, analytical results, arsenic, balls pass, base metals, billy creek, cedar creek, chemistry, chicken, chicken creek, clearwater creek, copper, copper creek, critical minerals, dennison fork, dggs, economic geology, exploration, fish lake, four mile lake, geochemical data, geochemical surveys, geochemistry, geologic, geology, george creek, glaman lake, gold, gold creek, gold prospect, granite, intrusion-hosted, iron creek, kechumstuk, kechumstuk creek, kechumstuk mountain, lab methods, ladue river, lake mansfield, lost chicken creek, lost chicken hill, major oxides, mansfield creek, metals, methods, mineral assessment, mineral deposit, mineral localities, mineral prospect, mineral resources, minerals, mining, minor oxides, molly creek, mosquito creek, mosquito fork, mount neuberger, myers fork, non-metals, ore deposit, ores, placer, placer gold, platinum, platinum gold, platinum group elements, porcupine creek, precious metals, prospecting sites, rare earth elements, resource assessment, resource information, resources, robertson river, round lake, sample location, sand creek, shindata creek, silver, sixtymile butte, square lake, stibnite creek, t lake, tanana river, tin, tok river, trace elements, trace geochemical, trace metals, wolf creek, wolf lake, yerrick creek
Organization: State of Alaska