|Quadrangle map, 1:250,000-scale||SR|
|Quadrangle map, 1:63,360-scale||D-7|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This mine is located in the SW1/4 section 10, T. 9 N., R. 1 E., of the Seward Meridian. It is at an elevation of 900 feet, on Sawmill Creek. This is location 16 of Cobb and Richter (1972), location 14 of MacKevett and Holloway (1977), location 6 of Cobb and Tysdal (1980), and location S-312 of Jansons and others (1984). The location is accurate to within a quarter of a mile.|
This deposit consists primarily of an auriferous, sulfide-bearing quartz vein, as much as 4 feet wide, in a fault that cuts Valdez Group rocks of Late Cretaceous age (Martin and others, 1915; Cobb and Tysdall, 1980). The fault strikes NE and dips 70SE. The fault walls are commonly striated and marked by a thin gouge. he vein is truncated at both ends by other faults. A second quartz vein, about 3 feet thick, is less faulted, but it carries only low gold values.
The primary vein contains arsenopyrite, pyrite, chalcopyrite, sphalerite, galena, and free gold. Crystals of arsenopyrite are also very abundant in the country rock.
This deposit may be an extension of the veins on the Slate Creek No. 1 (SR038) and Slate Creek No. 2 (SR040) prospects. All three veins are fault-controlled and are nearly on strike (Martin and others, 1915).A little placer gold was mined from the stream gravels of Sawmill Creek.
|Geologic map unit||(-149.263967021826, 60.8817464322962)|
|Mineral deposit model||Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a)|
|Mineral deposit model number||36a|
|Age of mineralization||Cretaceous or younger; the veins cut rocks of the Valdez Group of Late Cretaceous age.|
|Workings or exploration||
The underground workings at this mine are on the primary vein and consist of a single adit that is 60 to 70 feet long. Improvements include an arrastre mill, erected in 1906, that was driven by water power and capable of handling two 700-ton charges per day (Moffit, 1906). Nineteen tons of picked ore was processed and yielded approximately 25 ounces of gold (Hoekzema and Sherman, 1983).The U.S. Bureau of Mines visited the prospect in 1982 and collected four samples from the vein where it is exposed in and adjacent to Sawmill Creek. The adit was inaccessible at the time. The samples assayed from a trace to 0.04 ounce of gold per ton and a trace to 0.04 ounce of silver per ton (Jansons and others, 1984).
|Indication of production||Yes; small|
|Production notes||In 1906, approximately 25 ounces of gold were recovered from 19 tons of ore (Hoekzema and Sherman, 1983). Additional production might have occurred.|
Berg, H.C., and Cobb, E.H., 1967, Metalliferous lode deposits of Alaska: U.S. Geological Survey Bulletin 1246, 254 p.
Brooks, A.H., 1911, Geologic features of Alaskan metalliferous lodes: U.S. Geological Survey Bulletin 480-C, p. 43-93.
Cobb, E.H., and Richter, D.H., 1972, Metallic mineral resources map of the Seward quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-466, 2 sheets, scale 1:250,000.
Cobb, E.H., and Tysdal, R.G., 1980, Summaries of data on and list of references to metallic and selected nonmetallic mineral deposits in the Blying Sound and Seward quadrangle, Alaska: U.S. Geological Survey Open-File Report 80-621, 276 p.
Hoekzema, R.P., and Sherman, G.E., 1983, Mineral investigations in the Chugach National Forest, Alaska (Peninsula study area): U.S. Bureau of Mines in-house report; held at U.S. Bureau of Land Management Alaska State Office, Anchorage, 524 p.
Jansons, Uldis, Hoekzema, R.B., Kurtak, J.M., and Fechner, S.A., 1984, Mineral occurrences in the Chugach National Forest, southcentral Alaska: U.S. Bureau of Mines Mineral Land Assessment 5-84, 218 p., 2 sheets, scale 1:250,000.
MacKevett, E.M., Jr., and Holloway, C.D., 1977, Map showing metalliferous and selected non-metalliferous mineral deposits in the eastern part of southern Alaska: U.S. Geological Survey Open-File Report 77-169-A, 99 p., 1 sheet, scale 1:1,000,000.
Martin, G.C., Johnson, B.L., and Grant, U.S., 1915, Geology and mineral resources of Kenai Peninsula, Alaska: U.S. Geological Survey Bulletin 587, 243 p.
Mendenhall, W.C., 1900, A reconnaissance from Resurrection Bay to the Tanana River, Alaska, in 1898, in Walcott, C.D., Twentieth annual report of the United States Geological Survey, 1898-1899: Part VII - explorations in Alaska in 1898: U.S. Geological Survey Annual Report 20-VII, p. 265-340.
Moffit, F.H., 1905, Gold placers of Turnagain Arm, Cook Inlet, in Brooks, A.H., Report on progress of investigations of mineral resources of Alaska in 1904, U.S. Geological Survey Bulletin 259, p. 90-99.
Moffit, F.H., 1906, Gold fields of the Turnagain Arm region: U.S. Geological Survey Bulletin 277, p. 7-52.
Nelson, S.W., Dumoulin, J. A., and Miller, M.L., 1985, Geologic map of the Chugach National Forest, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1645-B, 16 p., 1 sheet, scale 1:250,000.
|Reporters||Jeff A. Huber (Anchorage)|
|Last report date||4/2/2000|