Rambler; Rambler Gold Mining Co. Prospect, Prince William Sound Mining District, Valdez-Cordova Census Area, Alaska, USAi

Regional Level Types
Rambler; Rambler Gold Mining Co. Prospect	Prospect
Prince William Sound Mining District	Mining District
Valdez-Cordova Census Area	Census Area
Alaska	State
USA	Country

Location: This prospect is about 1.3 miles southeast of Mount Cameron. It is at an elevation of about 3,400 feet in the center of W1/2 section 2, T. 8 S., R. 8 W., of the Copper River Meridian. This prospect is probably located to within one-quarter mile. It is locality 5 of Cobb and Matson (1972).
Geology: A gold-bearing, mineralized fault zone that averages about 1.5 feet in width cuts metaflysch of the Valdez Group (Jansons and others, 1984). The deposit was explored by two short shafts, a 227-foot long adit, and five trenches. At least one test shipment of ore was made in 1916 (Johnson, 1918). The U.S. Bureau of Mines collected three chip samples that contained as much as 0.64 ppm gold and 0.3 ppm of silver. This deposit is probably similar to other gold-bearing quartz veins cutting metaflysch of the Valdez Group in the southern Valdez quadrangle. Data summarized by Goldfarb and others (1997) show that gold-bearing quartz veins in the Valdez Group commonly contain pyrite, arsenopyrite, carbonate minerals, chlorite, and white mica and formed from water-rich fluids with 5 to 15 mole percent CO2 and significant amounts of CH4, N2, and H2S. The vein-forming fluid salinities were less than 8 percent, vein formation temperatures ranged from 225 to 375 degrees centigrade, and emplacement depths varied from 3 to 10 kilometers. The vein-forming fluids were produced by metamorphic devolatization reactions. Radiometric dating indicates that the veins formed from 57 to 49 Ma (Goldfarb and others, 1997, p. 171), when deep parts of the accreted Valdez Group flysch underwent high-grade metamorphism and partial melting (Hudson, 1994).
Workings: The deposit was explored by two short shafts, a 227-foot long adit, and five trenches; the total length of underground workings is about 400 feet (Cobb, 1979 OFR 79-1241]).
Age: Radiometric dating indicates that the gold-bearing quartz veins in the Valdez Group formed from 57 to 49 Ma (Goldfarb and others, 1997, p. 171), when deep parts of the accreted Valdez Group flysch underwent high-grade metamorphism and partial melting (Hudson, 1994).
Alteration: Country rocks to gold-bearing quartz veins in Valdez Group metaflysch can be variably silicified, carbonitized, and sericitized (Goldfarb and others, 1997).

Commodities (Major) - Au
Development Status: Undetermined.
Deposit Model: Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a)

Other Databases

Link to USGS - Alaska:	VA123

Other Regions, Features and Areas containing this locality

References