Ketchem Creek

Mine, Active

Alternative names

Holdem Creek

Commodities and mineralogy

Main commodities Au
Other commodities REE; Sn; W
Ore minerals allanite; cassiterite; gold; scheelite

Geographic location

Quadrangle map, 1:250,000-scale CI
Quadrangle map, 1:63,360-scale B-2
Latitude 65.484
Longitude -144.741
Nearby scientific data Find additional scientific data near this location
Location and accuracy The location is at the junction of Holdem and Ketchem Creeks. Most mining was on two sites along Ketchem Creek: 1) an area about 0.5 mile long beginning about 0.5 miles below the mouth of Holdem Creek, and 2) a 0.25 mile long area centered near the junction of Holdem and Ketchem Creeks. There has also probably been some mining on Holdem Creek.

Geologic setting

Geologic description

Ketchem Creek flows northeast, drains the north slope of Ketchem Dome, and eventually crosses into the Tintina fault zone, approximately 3 miles west of Circle Hot Springs. The western fork is called Holdem Creek. Before entering the Tintina fault zone, both Ketchem and Holdem Creeks are underlain by Tertiary granite bedrock described by Wiltse and others (1995) as a light gray biotite monzogranite to syenogranite. An east-trending mafic dike intrudes the granite on the east side of Ketchem Creek about a quarter of a mile above the junction with Holdem Creek. Most mining has occurred south of the fault zone. This fault zone is exposed by mining and is marked by deep-orange clay-rich gravel. The gravel to the north of the fault has spread laterally and two to three colors per pan can be collected there (Yeend, 1991).
Placer gravel in Ketchem Creek varies from 2 to 5 meters in thickness and is commonly overlain by 1 to 2 meters of muck. Gravel in the creek bed near the Hot Springs fault is up to 200 meters in width, most of which has been mined. Gold is concentrated in the lower 1 meter of gravel and is generally coarse and flattened. Nuggets of 1 to 3 ounces have been recovered. Fineness of gold about 0.783 Au and 0.207 Ag (Mertie, 1938). Heavy minerals in the gravel include scheelite, cassiterite, allanite, garnet, sphene and zircon (Wedow and others, 1954, p. 5; Cobb, 1973, p. 122, [B 1374]).
Unknown amount of gold was produced by placer mining from 1933 to 1949, 1975, 1981, and throughout the 1990s. Winter drifting and dragline excavators operated in the 1930s; however, large boulders were a serious problem just below the mouth of Holdem Creek. In 1991, Magic Circle, Inc., worked Ketchum Creek for 65 days and processed 17,230 tonnes (19,000 tons) of pay gravel during the season. Greenhorn Mining processed 7,646 cubic meters (10,000 cubic yards) of auriferous pay in the same year (Swainbank and others, 1991). More recent mining has been conducted on Ketchem Creek by Fred Wilkinson (C.J. Freeman, oral communication, 1998).
Geologic map unit (-144.743447107499, 65.4836384600948)
Mineral deposit model Placer gold deposit (Cox and Singer, 1986; model 39a)
Mineral deposit model number 39a

Production and reserves

Workings or exploration Placer mining occurred from 1933 to 1949, 1975, 1981, and throughout the 1990s. Winter drifting and dragline excavators operated in the 1930s; however, large boulders were a serious problem just below the mouth of Holdem Creek. In 1991, Magic Circle, Inc., worked Ketchum Creek for 65 days and processed 17,230 tonnes (19,000 tons) of pay gravel during the season. Greenhorn Mining processed 7,646 cubic meters (10,000 cubic yards) of auriferous pay in the same year (Swainbank and others, 1991). More recent mining has been conducted on Ketchem Creek by Fred Wilkinson (C.J. Freeman, oral communication, 1998).
Indication of production Yes; small
Production notes Unknown amount of gold produced by placer mining acitivity from 1933 to 1949, 1975, 1981, and throughout the 1990s. Production reported throughout the 1990s by Ed Lapp and Sons Mining (ESLM), Magic Circle, Inc. and Greenhorn Mining.

Additional comments

Ketchem Creek has also been spelled 'Ketchum'.

References

MRDS Number A012215; D002686

References

Lampright, R. L., 1996, Gold placer deposits near Fairbanks Alaska: Iron Fire Publications, Nederland, Colorado, 135 p.
Reporters C.J. Freeman, J.R. Guidetti Schaefer, A.S. Clements (Avalon Development Corporation)
Last report date 9/9/1998