Mountain View; Hickey Property Prospect, Prince William Sound Mining District, Valdez-Cordova Census Area, Alaska, USAi

Regional Level Types
Mountain View; Hickey Property Prospect	Prospect
Prince William Sound Mining District	Mining District
Valdez-Cordova Census Area	Census Area
Alaska	State
USA	Country

Location: This prospect is one-quarter mile east of Smith Mill on Mineral Creek. Its location is shown on the USGS Valdez A-7 topographic map (1996) with an adit symbol. It is locality 28 of Cobb and Matson (1972).
Geology: An iron-stained, gold-bearing quartz vein with wall quartz stringers in the hanging wall, cuts metaflysch of the Valdez Group. The vein, striking about east-west and dips steeply north; it is as much as 3 feet thick but pinches down to a few inches in some places (Brooks, 1912; Johnson, 1915). Sulfides are not common but do occur in local concentrations; pyrite and some galena have been identified. The workings include a short adit and open cuts, one of which exposed the vein for 30 feet of length. This vein is probably similar to others that are widespread 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 workings include a short adit and open cuts, one of which exposed the vein for 30 feet of length (Johnson, 1915).
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: Oxidation; the quartz vein is iron-stained. 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; (Minor) - Pb
Development Status: Undetermined.
Deposit Model: Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a)

Other Databases

Link to USGS - Alaska:	VA126

Other Regions, Features and Areas containing this locality

References