Unnamed (Sixmile Creek Headwaters) (ARDF #TN045) Ag, Cu, Pb

Unnamed (Sixmile Creek Headwaters)

Occurrence, Inactive

Commodities and mineralogy

Main commodities	Ag; Cu; Pb
Other commodities	Bi; Cd; Zn
Ore minerals	malachite; sulfides
Gangue minerals	quartz

Geographic location

Quadrangle map, 1:250,000-scale	TN
Quadrangle map, 1:63,360-scale	B-1
Latitude	65.38386
Longitude	-150.38833
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	This occurrence is at an elevation of about 2,000 feet on a ridge at the head of Sixmile Creek. The site is at Alaska Division of Geological and Geophysical Surveys (ADGGS) sample station 96BT274 (Liss and others, 1997), at the southwest corner of section 35, T. 7 N., R. 14 W., of the Fairbanks Meridian. The location is accurate within 500 feet.

Geologic setting

Geologic description The headwaters of Sixmile Creek drain an area underlain by Triassic to Mississippian, Rampart Group gabbro sills intercalated with basaltic flows, diabase, and diverse sedimentary rocks (Reifenstuhl and others, 1997 [RI 97-15a]). The rocks locally are penetratively deformed, regionally metamorphosed to low greenschist grade, fractured, sheared, and altered, and display mylonitic fabric. The Rampart Group rocks are both unconformably overlain by, and in high-angle fault contact with, Tertiary basalt and rhyolite. A sample (96BT274) of a 3-inch-thick, malachite-stained, quartz-sulfide vein in slightly chloritized greenstone/diabase at the head of Sixmile Creek contained 33.6 parts per million (ppm) silver, 4,637 ppm copper, 4,107 ppm zinc, 11.8 ppm cobalt, and 62.1 ppm bismuth (Liss and others, 1997). There is no record of exploration or mining at this site.
Geologic map unit	(-150.390846353591, 65.3833818435724)
Mineral deposit model	Quartz-sulfide vein?, polymetallic vein? (Cox and Singer, 1986; model 22c?).
Mineral deposit model number	22c?
Alteration of deposit	Chlorite.

Production and reserves

Workings or exploration	A sample (96BT274) of a 3-inch-thick, malachite-stained, quartz-sulfide vein in slightly chloritized greenstone/diabase at the head of Sixmile Creek contained 33.6 parts per million (ppm) silver, 4,637 ppm copper, 4,107 ppm zinc, 11.8 ppm cobalt, and 62.1 ppm bismuth (Liss and others, 1997). There is no record of exploration or mining at this site.
Indication of production	None

References

References Liss, S.A., Reifenstuhl, R.R., Clautice, K.H., Bundtzen, T.K., Newberry, R.J., Dover, J.H., and Blodgett, R.B., 1997, Rock geochemistry from the Rampart mining district: Alaska Division of Geological & Geophysical Surveys Public Data File 97-29G, 19 p., 1 DVD. Reifenstuhl, R.R., Dover, J.H., Pinney, D.S., Newberry, R.J., Clautice, K.H., Liss, S.A., Blodgett, R.B., Bundtzen, T.K., and Weber, F.R., 1997, Geologic map of the Tanana B-1 Quadrangle, central Alaska: Alaska Division of Geological & Geophysical Surveys Report of Investigation 97-15A, 17 p., 1 sheet, scale 1:63,360.
Reporters	D.J. Szumigala (ADGGS)
Last report date	5/18/2004