Oregon Creek

Prospect, Probably inactive

Commodities and mineralogy

Main commodities Ag; Cu; Pb; Zn
Ore minerals chalcopyrite; galena; pyrite; sphalerite

Geographic location

Quadrangle map, 1:250,000-scale EA
Quadrangle map, 1:63,360-scale C-2
Latitude 64.6294
Longitude -141.6935
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Oregon Creek prospect is located in the headwaters of Oregon Creek, about 0.6 mile southwest of Wallcutt Mountain. Oregon Creek is not labeled on the U.S. Geological survey topographic map of the Eagle C-2 quadrangle (1956). The prospect area is in section 27, T. 3 S., R. 30 E., of the Fairbanks Meridian; the location is accurate to within 1,000 feet. The Oregon Creek prospect is located within Doyon, Ltd. selected or conveyed land.

Geologic setting

Geologic description

The rocks in the area near the Oregon Creek prospect are Paleozoic quartzite and amphibolite, which are in fault contact with chlorite-quartz-mica schist and associated pyritic felsic tuff. These rocks are intruded by a Cretaceous(?) hornblende granodiorite stock (WGM Inc., 1998 [DLR 98-12]). The schist occurs as northeast-trending, elongate, roof pendants in granodiorite. Gray dacite dikes that contain as much as 8 percent disseminated pyrite trend north to northeast across the pluton and schist. The area is also cut by a series of late, sub-parallel, east-trending high-angle faults.
At the Oregon Creek prospect, pods and veins of galena and minor sphalerite cut altered hornblende granodiorite (Dashevsky and others, 1986). Minor chalcopyrite occurs in talus samples of brecciated intrusive rock on the ridge south of Wallcutt Mountain. The exploration target is a base and (or) precious metal vein system, but mineralization is also found in skarn and schist spatially associated with the granodiorite (WGM Inc., 1998 [DLR 98-12]). The Oregon Creek prospect appears to be the source of base-metal anomalies in stream silts to the south of Wallcutt Mountain. Sampling and mapping of an 8,000 foot by 8,000 foot area shows that lead, zinc, copper, and silver anomalies are spatially associated with chloritic schist, dacite dikes, faults, and locally with granodiorite. Silver is strongly associated with lead. Soil anomalies of lead are as much 2,630 ppm and indicate proximity to bedrock mineralization. Extensive areas exceed 100 ppm lead. The anomalies generally trend northeast, but this orientation might be the result of offset along the east-west faults. An 800-foot-wide soil anomaly that contains greater than 100 ppm lead is open to the west and coincides with a silver anomaly of as much as 14 ppm silver (WGM Inc., 1998 [DLR 98-12]).
A weak 3-mile by 2-mile magnetic anomaly coincides with the soil grid over the Oregon Creek prospect. The magnetic anomaly is distinctive relative to the low background magnetic values associated with the granodiorite. Weak linear-magnetic anomalies strike northeast, parallel to the trend of dacite dikes. The prospect coincides with a resistivity high, but no EM anomalies were identified. Champion I (EA048), Champion II (EA049), East Champion (EA047), and North Champion (EA046) are base-metal prospects within 7 miles of the Oregon Creek prospect. Lead isotopic ratios indicate a Late Cretaceous or early Tertiary age for the Champion II mineralization (U.S. Bureau of Mines, 1995); this suggests an intrusive origin for at least some of the mineralization in the area.
WGM Inc. conducted stream-sediment sampling, prospecting, and geologic mapping at the Oregon Creek prospect from 1975 to 1977 (Dashevsky and others, 1986). In 1996 and 1997, WGM Inc. sampled soil, and an EM-magnetics survey was commissioned by Ventures Resources Alaska (WGM Inc., 1998 [DLR 98-12]).
Geologic map unit (-141.69582676541, 64.6290725458296)
Mineral deposit model Cu skarn, Zn-Pb skarn, or polymetallic veins (Cox and Singer, 1986; models 18b, 18c, or 22c).
Mineral deposit model number 18b, 18c, or 22c
Age of mineralization Lead isotopic ratios indicate a Late Cretaceous or early Tertiary age for the nearby Champion II prospect (U.S. Bureau of Mines, 1995); similarities suggest the Oregon Creek prospect is also Late Cretaceous.
Alteration of deposit The hornblende granodiorite is altered (Dashevsky and others, 1986).

Production and reserves

Workings or exploration WGM Inc. conducted stream stream sediment sampling, prospecting, and geologic mapping at the Oregon Creek prospect from 1975 to 1977 (Dashevsky and others, 1986). In 1996 and 1997, WGM Inc. sampled soil, and an EM-magnetics survey was commissioned by Ventures Resources Alaska (WGM Inc., 1998 [DLR 98-12]).
Indication of production None

Additional comments

The Oregon Creek prospect is located within Doyon, Ltd. selected or conveyed land. For more information contact Doyon, Ltd., Fairbanks, Alaska.

References

References

Dashevsky, S.S., Nicol, D.L., and Bond, J., 1986, Mines, prospects, and geochemical anomalies on Doyon Limited regional overselection lands, Alaska, Blocks 1-8: Doyon, Ltd. Report 86-01a, 300 p. (Report held by Doyon, Ltd., Fairbanks, Alaska).
Lessman, J., and Holm, B., 1978, 1977 annual progress report, Doyon Project, Champion-Lead Creek area: Doyon, Ltd. Report 78-02. (Report held by Doyon, Ltd., Fairbanks, Alaska).
WGM Inc., 1977, Doyon Project, 1976 annual progress report, volume 1a, Blocks 1, 4, 5, 7, 8: Doyon, Ltd. Report 77-02a. (Report held by Doyon, Ltd., Fairbanks, Alaska).
WGM Inc., 1998, Ventures Resource Alaska projects, 1997 progress report, Champion property exploration: Doyon, Ltd. Report 98-12, 64 p. (Report held by Doyon, Ltd., Fairbanks, Alaska).
Reporters M.B. Werdon; R.L. Flynn
Last report date 5/1/2002