|Quadrangle map, 1:250,000-scale||MH|
|Quadrangle map, 1:63,360-scale||A-2|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The Dempsey prospect is in the main valley of the Chistochina River about one-half mile below the mouth of the Chisna River. The prospect is in the SE1/4NW 1/4 section 3, T. 22 S., R. 15 E., Fairbanks Meridian. The prospect may extend south as far as the mouth of Daisy Creek, which enters the Chistochina River about one mile below the abandoned site of Dempsey on the Mount Hayes A-2 quadrangle. The Dempsey prospect is locality 22 on figure 6 of Cobb (1979 [OFR 79-238]) and locality 17 in table 3 of Nokleberg and others (1991), and it is about one mile west in the Daisy Creek drainage.|
Geologic descriptionThe Dempsey prospect explored and attempted to develop auriferous bench gravels on the west side of the Chistochina River, a major glacier-fed river. Near Dempsey and as far south as the mouth of Daisy Creek, the flood plain of the modern Chistochina River is narrow, and there is an extensive bench developed on the west side of the river. The bench gravels are frozen locally; they contain small amounts of fine-grained gold. The area was prospected and a ditch was constructed in 1907; a prospect tunnel was reportedly driven in frozen bench gravels near Daisy Creek (Moffit, 1909; Brooks, 1910), but a mineable deposit was not found (Moffit, 1912).
|Geologic map unit||(-144.854718207268, 63.0383950579055)|
|Mineral deposit model||Placer Au, glacio-fluvial (Cox and Singer, 1986; model 39a).|
|Mineral deposit model number||39a|
|Age of mineralization||Pleistocene.|
|Workings or exploration||Explored by surface workings and a tunnel (adit) driven in frozen bench gravels (Moffit, 1909, 1912).|
|Indication of production||None|
Brooks, A.H., 1910, Mineral resources of Alaska, report on progress of investigations in 1909: U.S. Geological Survey Bulletin 442, 426 p.
Cobb, E.H., 1979, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Mount Hayes quadrangle, Alaska: U.S. Geological Survey Open-File Report 79-238, 140 p.
Moffit, F.H., 1909, Mining in the Kotsina-Chitina, Chistochina, and Valdez Creek regions: U.S. Geological Survey Bulletin 379-D, p. 153-160.
Moffit, F.H., 1912, Headwater regions of Gulkana and Susitna Rivers, Alaska, with accounts of the Valdez Creek and Chistochina placer districts: U.S. Geological Survey Bulletin 498, 82 p.
Moffit, F.H., 1944, Mining in the northern Copper River region, Alaska: U.S. Geological Survey Bulletin 943-B, p. 25-47.
Nokleberg, W.J., Lange, I.M., Roback, R.C., Yeend, Warren, and Silva, S.R., 1991, Map showing locations of metalliferous lode and placer mineral occurrences, mineral deposits, prospects, and mines, Mount Hayes quadrangle, eastern Alaska Range, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1996-C, 42 p., 1 sheet, scale 1:250,000.
|Reporters||W.T. Ellis (Alaska Earth Sciences), C.C. Hawley (Hawley Resource Group), and W.J. Nokleberg (USGS)|
|Last report date||7/12/2003|