Campbell and Boedeker

Prospect, Inactive

Commodities and mineralogy

Main commodities Au
Ore minerals gold; pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale HE
Quadrangle map, 1:63,360-scale A-1
Latitude 63.176
Longitude -147.3833
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect is at an elevation of about 3,900 feet in a small valley between Sunny Gulch and upper Timberline Creek. It is about 2.5 miles east of the old town of Denali, in SW1/4 section 16, T. 20 S., R. 2 E., Fairbanks Meridian. The location is accurate to within 250 feet.

Geologic setting

Geologic description

The Campbell and Boedecker prospect explores one of several mineral deposits in a belt south of Valdez Creek. The Valdez Creek area is underlain by pre-Upper Triassic pelitic clastic rocks, minor tuff, limestone lenses, and conglomerate. The rocks apparently vary abruptly in regional metamorphosed grade, from prehnite-pumpellyite through greenschist and amphibolite, to granulite. These rocks are intruded by Upper Jurassic alkali gabbro and by dioritic intrusions of Late Cretaceous and Early Tertiary age (Smith, 1981).
The bedding and foliation of the strata strike about N 75 E and dip steeply northwest. Strike-slip faults having a similar orientation are also present, particularly on the south side of Valdez Creek (Smith, 1981). On the north side of the creek, a northwest-dipping thrust fault in part explains an apparent 'telescoping' of the metamorphic rocks.
The deposit consists of two-foot-thick auriferous quartz vein that cuts sheared and locally pyritized diorite. The vein contains up to 50% pyrite; it strikes N 85 E and dips 68 N. A sample of sulfide concentrates assayed 1.9 ounces of gold per ton and 1.5 ounces of silver per ton. A sample of the sheared and pyritized diorite assayed 0.18 ounces of gold per ton (Tuck, 1938).
Geologic map unit (-147.385558800551, 63.1755516658145)
Mineral deposit model High-sulfide auriferous quartz vein.
Age of mineralization Late Cretaceous or younger.
Alteration of deposit Pyritization.

Production and reserves

Workings or exploration A 20-foot tunnel did not penetrate weathered zone but did give good exposure of vein and host rock. A sample of sulfide concentrates assayed 1.9 ounces of gold per ton and 1.5 ounces of silver per ton. A sample of the sheared and pyritized diorite assayed 0.18 ounces of gold per ton (Tuck, 1938).
Indication of production None

References