|Quadrangle map, 1:250,000-scale||WI|
|Quadrangle map, 1:63,360-scale||B-5|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is located along a southwest-flowing headwater tributary to the Malamute Fork, John River. It is about 4.5 miles southwest of the junction of Midas and Sixtymile Creeks. The occurrence is at an elevation of about 1,650 feet on the tributary, in the NE1/4 section 25, T. 29 N., R. 22 W., of the Fairbanks Meridian. The occurrence is the site of sample 519 in Dillon and others (1981 [AOF 133B]). The location is accurate within one-half mile.|
Two sources report Cu and Pb mineralization here. Dillon and others (1981, plate 1 [AOF 133B]) note a small area of Cu-Pb mineralization. Grybeck (1977, locality. 31) reports an occurrence of stratiform Cu, Pb, and Zn mineralization approximately 1.5 miles southeast of the site shown by Dillon and others. These two mineral occurrences may be the same.At sample locality 519 of Dillon and others (1981 [AOF 133B]), quartzite layers in marble and calcareous contains massive arsenopyrite and pyrite. These sulfides occur in bands that are parallel to the enclosing strata and are up to 10 cm thick and 20 m long. A sample contains 500 ppm arsenic, 219 ppb antimony, and 23% iron. Similar occurrences occur along strike for up to 1 km. Grybeck (1977), citing unpublished industry data, reports pyrrhotite, galena, sphalerite, and chalcopyrite in interbedded schist, quartzite, and limestone. The rocks in the area consist of Devonian, Skajit Limestone and Middle to Upper Devonian black calcareous schist and dark limestone (Dillon and others, 1986).
|Geologic map unit||(-152.36524688093, 67.3078329982551)|
|Mineral deposit model||Polymetallic replacement deposit? (Cox and Singer, 1986; model 19a?).|
|Mineral deposit model number||19a?|
|Workings or exploration||Eight prospecting sites were located in the area in 1976 (Grybeck, 1977).|
|Indication of production||None|
Cobb, E.H., 1981, Summaries of data on and lists of references to metallic and selected nonmetallic mineral occurrences in the Wiseman quadrangle, Alaska; Supplement to Open-File Report 76-340; Part B, Lists of references to January 1, 1981: U.S. Geological Survey Open-File Report 81-732-B, 22 p.
Dillon, J.T., Cathrall, J.B., and Moorman, M.A., 1981, Geochemical reconnaissance of the southwest Wiseman quadrangle-summary of data on rock samples: Alaska Division of Geological and Geophysical Surveys Open-File Report 133B, 164 p.
|Reporters||J.M. Britton (Anchorage)|
|Last report date||8/9/2002|