Lower Dahl Creek

Mine, Inactive

Commodities and mineralogy

Main commodities Au
Other commodities Nephrite
Ore minerals gold

Geographic location

Quadrangle map, 1:250,000-scale SH
Quadrangle map, 1:63,360-scale D-2
Latitude 66.957
Longitude -156.885
Nearby scientific data Find additional scientific data near this location
Location and accuracy The lower Dahl Creek placer deposit is about 3/4 mile north of the Dahl Creek landing strip and about 4 miles by road from Kobuk. The deposit, which extends for about a mile along the creek, is in sections 15, 16, and 21, T. 18 N., R. 9 E., of the Kateel River Meridian. Mayfield and Grybeck (1978), location 30.

Geologic setting

Geologic description

At the lower Dahl Creek placer deposit, gold occurs on false bedrock or in glacial drift commonly less than 10 ft. below the surface. The gold is irregularly distributed through the gravel. The gold is fairly coarse but with few nuggets. It was worth about $16.50 per ounce in 1931. Where the stream valley opens into the Kobuk Valley three shafts were sunk through glacial till, two to 25 feet and one to 80 feet. These test holes went through alternating beds of sand and gravel dipping slightly to the south and failed to reach bedrock. Fine colors of gold were found in the sand and gravel in all the holes, but no regular pay streak was found. One-half mile below the mouth of the canyon the depth to bedrock varies from 2 to 8 feet. Two lines, at 500 foot spacing, of three shafts each cross the stream valley in this area. The shafts were sunk to 25 feet and did not reach bedrock. Gold reportedly occurs in a paleo-channel. The ground mined in this area was estimated to yield about $1.02 per cubic yard (Reed, 1931).
Bedrock in the area consists of conglomeratic metasediments and black phyllite of early to mid-Paleozoic age. The black phyllite is cut by numerous quartz veins. Stream gravel is medium fine, containing well waterworn pieces up to 2 inches in diameter. Distributed throughout the gravel are numerous large boulders of greenstone or metamorphosed conglomerate, and an occasional boulder of gneissic granite (Reed, 1931).
Geologic map unit (-156.887731011828, 66.9564499525084)
Mineral deposit model Placer Au-PGE (Cox and Singer, 1986; model 39a).
Mineral deposit model number 39a
Age of mineralization Quaternary.

Production and reserves

Workings or exploration Gold was first discovered in 1898 and the claims have been worked more or less consistently up to 1968. Starting in 1950, nephrite boulders were recovered during the mining process. This continued into the early 1970s. In 1988 and 1989 NANA took jig samples from each of the claim blocks in an attempt to complete a patenting application on the claims. These data are available by request from NANA Regional Corp.
Indication of production Yes; small
Production notes Total production from Dahl Creek (also see ARDF number SH003) is estimated to be 15,000 ounces to more than 17,000 ounces (Degenhart and others, 1978).

Additional comments

Dahl Creek was the main placer gold producer in the district. Nephrite boulders were recovered from stream gravels during placer mining starting in the 1950s. Nephrite was produced from the creek up to the 1970s. The land is owned by NANA Regional Corporation.

References

MRDS Number A011877

References

WGM Staff, 1980, Non-fuel mineral resources of Alaska: Anchorage, Alaska, WGM, Inc. Unpublished report for Phillips Petroleum Company, 320 p. (Report held by NANA Regional Corporation, Anchorage, Alaska).
Reporters Anita Williams (Anchorage, AK)
Last report date 12/16/1999