Unnamed (Burroughs Bay )

Prospect, Undetermined

Commodities and mineralogy

Main commodities Mo
Other commodities U
Ore minerals molybdenite; pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale KC
Quadrangle map, 1:63,360-scale D-4
Latitude 55.994
Longitude -131.297
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect is at sea level on the north side of Burroughs Bay, about 4.2 miles northwest of Pt. Whaley. The site is in section 11, T. 68 S., R. 91 E., of the Copper River Meridian. It corresponds to loc. 26 in Elliott and others (1978). The location is accurate within a few hundred feet.

Geologic setting

Geologic description

The country rocks in the area of this prospect include a Cretaceous foliated quartz diorite batholith; metamorphic roof pendants in the batholith; and a Miocene granite and quartz porphyry stock and associated dikes that intrude the batholith and the metamorphic rocks (Berg and others, 1978, p. 12-13; Berg and others, 1988, p. 23). The outcrop area of the stock and associated dikes is about a square mile. The deposit is in the Miocene granite and quartz porphyry and consists of molybdenite-bearing quartz fissure veins and molybdenite coatings on fracture surfaces, and of veins and disseminations of pyrite (Berg and others, 1978, p. 12-13 and table 2). Analyses of several samples of molybdenite-bearing quartz porphyry dikes showed up to 100 ppm Mo and traces of U (Koch and Elliott, 1978 [OFR 78-156A]). The mineralogy, hostrock, age, and setting indicate that this is a porphyry molybdenum deposit similar in type and origin to the much larger one at Quartz Hill (KC105).
Geologic map unit (-131.298698609227, 55.9936330584942)
Mineral deposit model Porphyry molybdenum, low-F (Cox and Singer, 1986; model 21b)
Mineral deposit model number 21b
Age of mineralization Miocene.
Alteration of deposit Pyritization and silicification.

Production and reserves

Workings or exploration The deposit has been examined by private interests, but none of their findings have been made public. A grade of 0.06% molybdenite has been reported (Eakins and others, 1983, p. 46).
Indication of production None

Additional comments

Also see Quartz Hill (KC105).