| Quadrangle map, 1:250,000-scale | AN |
|---|---|
| Quadrangle map, 1:63,360-scale | D-6 |
| Latitude | 61.83 |
| Longitude | -149.24 |
| Nearby scientific data | Find additional scientific data near this location |
| Location and accuracy | At the headwaters of Archangel Creek, approximately 1,000 ft northeast of the end of the Fern Mine Road. Accurate within 1,000 ft. This is locality 19 of Cobb (1972) and locality 16 of MacKevett and Holloway (1977). |
Geologic descriptionA 1 to 10 inch thick quartz vein cuts quartz diorite of the Late Cretaceous Willow Creek Pluton. The vein contains a very rich streak, 1/2 to 2 inches thick, with abundant coarse specks of free gold. The vein is reportedly traceable for 1,500 ft (Capps, 1915; 1919). The Willow Creek Pluton is a zoned pluton. The outer part consists of hornblende quartz diorite and lesser hornblende tonalite; the core consists of hornblende-biotite granodiorite, and lesser hornblende-biotite quartz monzodiorite and biotite quartz monzonite. Wall-rock alteration within a few inches of the vein is intense, but seldom extends more than 10 to 12 inches beyond the quartz filling. Sericitization and carbonate alteration predominate, but there is some pyritization and in the outer parts of the alteration zone chloritization is present (Ray, 1954). | |
| Geologic map unit | (-149.242209285549, 61.8294727577684) |
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| Mineral deposit model | Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a) |
| Mineral deposit model number | 36a |
| Age of mineralization | Late Cretaceous or younger; vein cuts the Late Cretaceous Willow Creek Pluton. |
| Alteration of deposit | Wall-rock alteration within a few inches of the vein is intense, but seldom extends more than 10 to 12 inches beyond the quartz filling. Sericitization and carbonate alteration predominate, but there is some pyritization and in the outer parts of the alteration zone chloritization is present (Ray, 1954). |
| Workings or exploration | Staked in 1913. Development included two tunnels, 25 ft and 60 ft in length. Mill and material for tram was present but not installed in 1917 (Capps, 1915; 1919). Probably eventually became part of the Fern property (AN005) (Cobb, 1979). |
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| Indication of production | Undetermined |
| MRDS Number | A106232 |
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| Reporters | D.P. Bickerstaff (USGS contractor) |
| Last report date | 7/30/1998 |