Divide Creek

Prospect, Probably inactive

Commodities and mineralogy

Main commodities Au
Ore minerals gold
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale NM
Quadrangle map, 1:63,360-scale D-1
Latitude 64.8374
Longitude -165.2717
Nearby scientific data Find additional scientific data near this location
Location and accuracy Divide Creek is a short, west tributary to upper Nome River. Its headwaters are at the divide between the Nome River and Stewart River drainages. Divide Creek enters Nome River about 2 miles south of the confluence of Hudson Creek and Nome River. This location is just downslope of where the Campion Ditch crosses Divide Creek. It is locality 104 of Cobb (1972 [MF 463], 1978 [OFR 78-93]).

Geologic setting

Geologic description

Divide Creek is a small creek that heads in the divide between the Stewart River and Nome River drainages. Some sluicing of placer gold took place here in 1903 (Collier and others, 1908). Parts of the creek flow over deep gravel deposits of glacial origin (Collier and others, 1908). Nearby glacial and fluvio-glacial deposits are part of the modified drift of the Nome River glaciation and the modified drift of the Stewart River glaciation (Bundtzen and others, 1994). During construction of the Campion Ditch, quartz with attached gold was found near here; one quartz fragment with gold weighed 0.75 pound (Moffit, 1913).
Moffit (1913) thought the placer gold was derived from near Boer Mountain; recent hardrock exploration has found significant lode gold deposits nearby, for example at the Divide prospect (NM058). Some of the gold at Divide Creek could also been derived by reworking of weakly auriferous glacial drift of the Nome River and Stewart River glaciations.
Bedrock is not exposed in Divide Creek, but nearby it appears to be graphitic and calcareous quartz schist (Hummel, 1962 [MF 248]). This schist may be lower grade than most of the metamorphic rocks immediately to the north on Boer Mountain. (Projections from mapping to the west suggest that the western rocks could be biotite-bearing [Sainsbury, Hummel, and Hudson, 1972; Bundzten and others, 1994]).
The bedrock is probably part of the Nome Group derived from Proterozoic to early Paleozoic protoliths (Till and Dumoulin, 1994). The Nome Group underwent regional blueschist facies metamorphism in the Late Jurassic or Early Cretaceous (Sainsbury, Coleman, and Kachadoorian, 1970; Forbes and others, 1984; Thurston, 1985; Armstrong and others, 1986; Hannula and McWilliams, 1995). The blueschist facies rocks were recrystallized to greenschist facies or higher metamorphic grades in conjunction with regional extension, crustal melting, and magmatism in the mid-Cretaceous (Hudson and Arth, 1983; Miller and Hudson, 1991; Miller and others, 1992; Dumitru and others, 1995; Hannula and others, 1995; Hudson, 1994; Amato and others, 1994; Amato and Wright, 1997, 1998). The ultimate source of the placer deposits at Divide Creek are lode gold deposits related to the higher temperature metamorphism in the mid-Cretaceous (Apodoca, 1994; Ford, 1993 (thesis); Ford and Snee, 1996; Goldfarb and others, 1997).
Geologic map unit (-165.274324314685, 64.8366420651806)
Mineral deposit model Placer Au (Cox and Singer, 1986; model 39a).
Mineral deposit model number 39a
Age of mineralization Quaternary.

Production and reserves

Workings or exploration Collier and others (1908) noted some mining in 1903 and plans, probably not carried out, for hydraulic mining. Moffit (1913, p. 100) found no evidence of extensive mining when he visited the area, but did note that the placer gold could have come from the south slopes of Boer Mountain.
Indication of production Yes; small

References

MRDS Number A012911

References

Apodoca, L.E., 1994, Genesis of lode gold deposits of the Rock Creek area, Nome mining district, Seward Peninsula, Alaska: Boulder, Colorado, University of Colorado, Ph.D. dissertation, 208 p.
Armstrong, R.L., Harakal, J.E., Forbes, R.B., Evans, B.W., and Thurston, S.P., 1986, Rb-Sr and K-Ar study of metamorphic rocks of the Seward Peninsula and southern Brooks Range, Alaska, in Evans, B.W., and Brown, E.H., eds., Blueschists and eclogites: Geological Society of America Memoir 164, p. 184-203.
Ford, R.C., 1993, The geology, geochemistry, and age for lode sources of placer gold deposits in the Seward Peninsula: Technical Presentation, Denver Region Exploration Geologists' Society, November 6, 1993, Denver, Colo., unpaginated.
Ford, R.C., and Snee, L.W., 1996, 40Ar/39Ar thermochronology of white mica from the Nome district, Alaska--The first ages of lode sources to placer gold deposits in the Seward Peninsula: Economic Geology, v. 91, p. 213-220.
Goldfarb, R.J., Miller, L.D., Leach, D.L., and Snee, L.W, 1997, Gold deposits in metamorphic rocks in Alaska, in Goldfarb, R.J., and Miller, L.D., eds., Mineral Deposits of Alaska: Economic Geology Monograph 9, p. 151-190.
Hannula, K.A., and McWilliams, M.O., 1995, Reconsideration of the age of blueschist facies metamorphism on the Seward Peninusla, Alaska, based on phengite 40Ar/39Ar results: Journal of Metamorphic Geology, v. 13, p. 125-139.
Hannula, K.A., Miller, E.L., Dumitru, T.A., Lee, Jeffrey, and Rubin, C.M., 1995, Structural and metamorphic relations in the southwest Seward Peninsula, Alaska; Crustal extension and the unroofing of blueschists: Geological Society of America Bulletin, v. 107, p. 536-553.
Hudson, T.L., 1994, Crustal melting events in Alaska, in Plafker, G., and Berg, H. C., eds., The Geology of Alaska: Geological Society of America, DNAG, The Geology of North America, Vol. G-1, p. 657-670.
Hudson, T.L., and Arth, J. G., 1983, Tin granites of Seward Peninsula, Alaska: Geological Society of America Bulletin, v. 94, p. 768-790.
Miller, E.L., Calvert, A.T., and Little, T.A., 1992, Strain-collapsed metamorphic isograds in a sillimanite gneiss dome, Seward Peninsula, Alaska: Geology, v. 20, p. 487-490.
Thurston, S.P., 1985, Structure, petrology, and metamorphic history of the Nome Group blueschist terrane, Salmon Lake area, Seward Peninsula, Alaska: Geological Society of America Bulletin, v. 96, p. 600-617.
Till, A.B., and Dumoulin, J.A, 1994, Geology of Seward Peninsula and St. Lawrence Island, in Plafker, G., and Berg, H.C., eds., The Geology of Alaska: Geological Society of America, DNAG, The Geology of North America, v. G-1, p. 141-152.
Reporters C.C. Hawley and Travis L. Hudson
Last report date 10/22/1999