Unnamed (near VABM Good)

Prospect, Inactive

Commodities and mineralogy

Main commodities Cu; Mo; W
Other commodities Ag; Au; Bi
Ore minerals brochantite; chalcopyrite; chrysocolla; cuprite; malachite; molybdenite; powellite; scheelite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale EA
Quadrangle map, 1:63,360-scale A-6
Latitude 64.2355
Longitude -143.9094
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect covers the southern and western peaks near VABM Good; it is about 2 miles west of Mount Harper in the headwaters of the Healy River. The coordinates are the approximate center of the prospect, in section 11, T. 8 S., R. 19 E., of the Fairbanks Meridian; the location is accurate. The Mount Harper area is locality 6 of Cobb (1973 [MF-393]). This prospect is located within Doyon, Ltd. selected or conveyed land.

Geologic setting

Geologic description

Biotite granodiorite of the Mount Harper intrusive complex comprises the peak around VABM Good (U.S. Bureau of Mines, 1995). Biotite from the Mount Harper granite gives a 40Ar/39Ar plateau age of 105.8 +/- 0.4 Ma (Newberry and others, 1996). An abrupt 90-gamma magnetic high over the southern summit of VABM Good coincides with an area of molybdenum-tungsten-bismuth enrichment in quartz veins (Dashevsky and others, 1986). Quartz-vein density is as high as 25 veins per square foot 500 feet west of VABM Good. About 800 feet southeast of the summit, abundant vuggy-quartz float contains malachite, brochantite, chrysocolla, chalcopyrite, and cuprite and minor scheelite, powellite, and molybdenite. Geochemical sampling suggests a molybdenum-tungsten stockwork system centered about 1,000 feet southwest of VABM Good. The magnetic anomaly in the area suggests an underlying skarn that extends to the Larsen Ridge skarn prospect (EA091) to the northeast. Several other molybdenum-tungsten prospects are in the Mount Harper area, including Airplane Ridge (EA093), Quartz-Porphyry (EA094), and Section 21 (EA095).
Molybdenite in a quartz vein on the southern slope of Mount Harper was first reported by Chapin (1919). Anomalous tungsten, copper, and molybdenum values were found during a stream-sediment reconnaissance in the Mount Harper area by WGM Inc. in 1975; this was followed by geologic mapping and rock sampling in 1976 (Dashevsky and others, 1986). An airborne magnetic survey in 1979 by Union Carbide Corp. discovered the magnetic anomaly near the summit of VABM Good; this was followed by geologic mapping, rock sampling, and ground magnetics in 1980. In 1981, a drill hole by Union Carbide Corp. was abandoned at 623 feet due to adverse ground conditions; no significant mineralized intercepts were penetrated.
Geologic map unit (-143.911719852813, 64.2351420288718)
Mineral deposit model W skarn or porphyry Mo (Cox and Singer, 1986; models 14a and 21b).
Mineral deposit model number 14a or 21b
Age of mineralization Cretaceous or younger.

Production and reserves

Workings or exploration Molybdenite in a quartz vein on the southern slope of Mount Harper was first reported by Chapin (1919). Anomalous tungsten, copper, and molybdenum values were found during a stream-sediment reconnaissance in the Mount Harper area by WGM Inc. in 1975; this was followed by geologic mapping and rock sampling in 1976 (Dashevsky and others, 1986). An airborne magnetic survey in 1979 by Union Carbide Corp. discovered the magnetic anomaly near the summit of VABM Good; this was followed by geologic mapping, rock sampling, and ground magnetics in 1980. In 1981, a drill hole by Union Carbide Corp. was abandoned at 623 feet due to adverse ground conditions; no significant mineralized intercepts were penetrated.
Indication of production None

Additional comments

The VABM Good 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).
DiMarchi, J.J., Weglarz, T.B., Dickey, C.F., Laux, D.P., Smith, M.T., Toro, J., and Kurtz, J.P., 1991, Central Alaska Gold Co. 1990 annual report, Alaska field operations - Doyon option volume 10: Doyon, Ltd. Report 91-8g. (Report held by Doyon, Ltd., Fairbanks, Alaska).
DiMarchi, J.J., Weglarz, T.B., Dickey, C.F., Laux, D.P., Smith, M.T., Toro, J., and Kurtz, J.P., 1991, Central Alaska Gold Co. 1990 annual report, Alaska field operations - Doyon option volume 1: Doyon, Ltd. Report 91-8a. (Report held by Doyon, Ltd., Fairbanks, Alaska).
DiMarchi, J.J., Weglarz, T.B., Dickey, C.F., Laux, D.P., Smith, M.T., Toro, J., and Kurtz, J.P., 1991, Central Alaska Gold Co. 1990 annual report, Alaska field operations - Doyon option volume 2, analytical results, geochemical results part A: Doyon, Ltd. Report 91-8b. (Report held by Doyon, Ltd., Fairbanks, Alaska).
DiMarchi, J.J., Weglarz, T.B., Dickey, C.F., Laux, D.P., Smith, M.T., Toro, J., and Kurtz, J.P., 1991, Central Alaska Gold Co. 1990 annual report, Alaska field operations - Doyon option volume 2, analytical results, geochemical results part B: Doyon, Ltd. Report 91-8c. (Report held by Doyon, Ltd., Fairbanks, Alaska).
Hughs, M.A., and Siems, P.L., 1981, 1980 Lucky 13 project area report: Doyon, Ltd. Report 81-03. (Report held by Doyon, Ltd., Fairbanks, Alaska).
Huskey, G.F., 1981, 1981 Lucky 13 project area report: Doyon, Ltd. Report 82-49, 7 p. (Report held by Doyon, Ltd., Fairbanks, Alaska).
Union Carbide Corp., 1980, 1979 Lucky 13 project area report: Doyon, Ltd. Report 80-16 (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, Veta property, 1997 annual report, volume 1: Doyon, Ltd. Report 98-10, 227 p. (Report held by Doyon, Ltd., Fairbanks, Alaska).
Reporters M.B. Werdon; R.L. Flynn
Last report date 5/1/2002