Unnamed Occurrence (ARDF - NM112; Windy Creek), Nome Mining District, Nome Census Area, Alaska, USAi

Regional Level Types
Unnamed Occurrence (ARDF - NM112; Windy Creek)	- not defined -
Nome Mining District	Mining District
Nome Census Area	Census Area
Alaska	State
USA	Country

Location: This graphite occurrence is on the ridge crest between Windy Creek and an unnamed east tributary to the Cobblestone River. It is at 2,400 feet elevation and about 500 feet south of saddle 2345. It is locality 36 of Hummel (1962 [MF 248]).
Geology: This is one of three graphite occurrences (this occurrence, NM023, and NM113) mapped by Hummel (1962 [MF 248]) in this part of the Kigluaik Mountains. At NM023, graphite with biotite is disseminated in schist and also occurs in segregations to 18 inches thick. It also occurs as sparse disseminations in pegmatite. Moffit (1913, p. 135-136) described a graphite-rich layer 8 inches thick between pegmatite and schist walls. This occurrence probably also includes disseminations and segregations of graphite in the host schist. The graphite-bearing rocks are upper amphibolite facies schist and gneiss that are probably derived from Precambrian protoliths (Sainsbury, 1972; Bunker and others, 1979; Till and Dumoulin, 1994). They are thought to have undergone regional high-pressure metamorphism along with many other rocks of Seward Peninsula in the Late Jurassic or Early Cretaceous (Sainsbury, Coleman, and Kachadoorian, 1970; Forbes and others, 1984; Thurston, 1985; Patrick, 1988; Patrick and Evans, 1989; Armstrong and others, 1986; Hannula and McWilliams, 1995). Higher temperature metamorphism overprinted these rocks in conjunction with regional extension, crustal melting, and magmatism in the mid-Cretaceous (Throckmorton and Hummel, 1979; Till, 1983; Evans and Patrick, 1987; Leiberman, 1988; Patrick and Leiberman, 1988; Miller and Hudson, 1991; Miller and others, 1992; Dumitru and others, 1995; Hannula and others, 1995; Hudson and Arth, 1983; Hudson, 1994; Amato and others, 1994; Amato and Wright, 1997, 1998). Uplift of the higher temperature metamorphic rocks took place in the mid- to Late Cretaceous and in the Eocene (Calvert, 1992; Dumitru and others, 1995).
Age: Mid-Cretaceous; the age of high-grade metamorphism.

Commodities (Major) - Graphite
Development Status: None
Deposit Model: Graphite disseminations and segregations in amphibolite facies metamorphic rocks

Other Databases

Link to USGS - Alaska:	NM112

Other Regions, Features and Areas containing this locality

References