Trace-element geochemical data from stream sediments collected in the Tok River area, Tanacross A-5 and A-6 quadrangles, Alaska in 2016
Dates
Publication Date
2016
Time Period
2016
File Modification Date
2016-11-04 12:54:00
Citation
Naibert, T.J., Werdon, M.B., Lande, Lauren, and Wypych, Alicja, 2016, Trace-element geochemical data from stream sediments collected in the Tok River area, Tanacross A-5 and A-6 quadrangles, Alaska in 2016: Alaska Division of Geological & Geophysical Surveys, http://dx.doi.org/10.14509/29688.
Summary
In 2016, geologists from the Alaska Division of Geological & Geophysical Surveys (DGGS) and University of Alaska Fairbanks carried out a two-part geologic mapping and geochemical sampling project in the Tok River area of the Tanacross A-5 and A-6 quadrangles (June 12-26 and July 8-26). This report provides results of stream-sediment sampling for trace-element geochemistry. An initial suite of sediment samples was collected from streams draining known gold occurrences, including the Stibnite Creek and Noah prospects, and numerous prospects in the White Gold area. These samples were split in half and the two splits were sieved to -200 mesh and -80 mesh, respectively. The splits were then both analyzed to determine which size fraction [...]
Summary
In 2016, geologists from the Alaska Division of Geological & Geophysical Surveys (DGGS) and University of Alaska Fairbanks carried out a two-part geologic mapping and geochemical sampling project in the Tok River area of the Tanacross A-5 and A-6 quadrangles (June 12-26 and July 8-26). This report provides results of stream-sediment sampling for trace-element geochemistry. An initial suite of sediment samples was collected from streams draining known gold occurrences, including the Stibnite Creek and Noah prospects, and numerous prospects in the White Gold area. These samples were split in half and the two splits were sieved to -200 mesh and -80 mesh, respectively. The splits were then both analyzed to determine which size fraction was best for identifying gold anomalies in this part of the Alaska Range. In most samples, the -200 mesh fraction showed higher gold levels, and hence, all additional samples we collected were analyzed at -200 mesh. In some -80 mesh samples, gold and tungsten appear to show "nugget" effects not seen in the -200 mesh samples. The other trace elements are largely equivalent between the two mesh sizes. The second suite of samples was collected throughout the map area from streams draining color anomalies, from areas where DGGS mapping identified igneous rocks upstream, and from areas with suspected potential for base-metal or gold mineralization. Highlights of the analytical results include two samples draining the Noah prospect with greater than 1 part per million gold. The analytical data tables associated with this report are available in digital format as comma-separated value (CSV) files.
The combination of insufficient detailed geologic mapping, historical and current industry interest in the adjacent mineralized areas, and the recently published geophysical data prompted the DGGS Mineral Resources section to conduct a stream-sediment sampling program in conjunction with geologic mapping in the Tok River area.
