Chicago Creek

Mine, Inactive

Commodities and mineralogy

Main commodities Au
Ore minerals gold

Geographic location

Quadrangle map, 1:250,000-scale TN
Quadrangle map, 1:63,360-scale A-1
Latitude 65.17974
Longitude -150.35932
Nearby scientific data Find additional scientific data near this location
Location and accuracy Placer mining has occurred on Chicago creek near its mouth. The site is at the intersection of Chicago Creek and the Thanksgiving drainage ditch, in the northeast quarter of section 15, T. 4 N., R. 14 W., of the Fairbanks Meridian. The location is accurate within 0.5 mile. The site is included in location 38 of Cobb (1972), and roughly corresponds with the site for Chicago Creek, U.S. Bureau of Land Management MAS number 0020480047.

Geologic setting

Geologic description

The Chicago Creek area is marked by low, predominantly alluvium-covered topography (Chapman and others, 1982). The area is underlain by Mesozoic clastic sedimentary rocks including sandstone, siltstone, and shale, that are cut by thrust faults and locally intruded by Cretaceous monzodiorite (Reifenstuhl and others, 1998).
Gold was first reported on Chicago Creek in 1904 (Hess, 1908). Little work was reported, however, until 1935 through 1937 (Chapin, 1919; Smith, 1937, 1938, 1939), when Chicago Creek was considered a significant producer in the Eureka area. The gravels were 5 to 6 feet thick and overlay dark gray shale. According to Cobb (1981), nuggets 0.3 to 0.8 inch in diameter were found, some still attached to quartz. Mining of unknown extent was reported in 1973 (Cobb, 1981).
Geologic map unit (-150.361805866629, 65.1792594089268)
Mineral deposit model Placer Au (Cox and Singer, 1986; model 39a).
Mineral deposit model number 39a
Age of mineralization Quaternary.

Production and reserves

Workings or exploration Gold was first reported on Chicago Creek in 1904 (Hess, 1908). Little work was reported, however, until 1935 through 1937 (Chapin, 1919; Smith, 1937, 1938, 1939), when Chicago Creek was considered a significant producer in the Eureka area. The gravels were 5 to 6 feet thick and overlay dark gray shale. According to Cobb (1981), nuggets 0.3 to 0.8 inch in diameter were found, some still attached to quartz. Mining of unknown extent was reported in 1973 (Cobb, 1981).
Indication of production Yes; small
Production notes According to Cobb (1981), angular nuggets 0.3 to 0.8 inch in diameter were recovered from the Chicago Creek placer. Production figures have not been made public, but production probably was small, despite local rumors of significant production in 1935-1937.

References

MRDS Number A015213

References

Reporters G.E. Graham (ADGGS)
Last report date 11/9/2000