|Quadrangle map, 1:250,000-scale||EA|
|Quadrangle map, 1:63,360-scale||B-1|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is located in an outcrop on the east side of the Taylor Highway near the mouth of Columbia Creek. The occurrence is in section 35, T. 5 S., R. 32 E., of the Fairbanks Meridian. The location is accurate within 1,000 feet.|
Geologic descriptionThe rocks in the vicinity of this occurrence are predominantly Paleozoic greenschist-facies black carbonaceous quartzite (Dusel-Bacon and others, 1998). Approximately 1.5 miles to the south, these rocks are in fault contact with Paleozoic amphibolite-facies metamorphic rocks (Foster, 1976). Sulfides occur in a carbon-free or carbon-poor quartzite that is interpreted to be metachert or possibly a metamorphosed exhalite(?). This occurrence is interpreted to be a sedimentary-exhalative massive sulfide occurrence by Dusel-Bacon and others (1998), but the presence of possible felsic metavolcanic rocks indicates that it could be a Kuroko-type volcanogenic massive sulfide deposit. The host rock is a tan to pale-gray quartzite with minor muscovite. The quartzite is interlayered with more muscovite-rich quartzite and muscovite schist, which may have originally been felsic tuff. Sulfides occur as discontinuous lenses, 1 to 2 centimeters thick, that contain sphalerite, and lesser galena and chalcopyrite (Dusel-Bacon and others, 1998). A sample of this material contains 8.1 percent zinc, 100 ppm cadmium, 38 ppb gold, and 132 ppm mercury.
|Geologic map unit||(-141.353899438519, 64.4309964279908)|
|Mineral deposit model||Sedimentary exhalative massive sulfide or Kuroko-type volcanogenic massive sulfide (Cox and Singer, 1986; model 31a or 28a).|
|Mineral deposit model number||31a or 28a|
|Age of mineralization||Paleozoic or younger.|
|Indication of production||None|
Dusel-Bacon, Cynthia, Bressler, J.R., Takaoka, H., Mortensen, J.K., Oliver, D.H., Leventhal, J.S., Newberry, R.J., and Bundtzen, T.K., 1998, Stratiform zinc-lead mineralization in Nasina assemblage rocks of the Yukon-Tanana Upland in east-central Alaska: U.S. Geological Survey Open-File Report 98-340, 26 p. (World Wide Web URL, http://caldera.wr.usgs.gov/syngenms/OF98-340.html).
|Last report date||5/1/2002|