Straight Creek Springs

Occurrence, Inactive

Commodities and mineralogy

Main commodities Cu; Ni; Zn
Other commodities Mo
Ore minerals iron oxides
Gangue minerals silicrete minerals

Geographic location

Quadrangle map, 1:250,000-scale MG
Quadrangle map, 1:63,360-scale A-3
Latitude 62.17
Longitude -154.388
Nearby scientific data Find additional scientific data near this location
Location and accuracy Straight Creek Springs (more than a dozen distinct springs are known) are located on the west limit of Straight Creek valley just down stream from the Chip Loy deposit (MG032). The springs occur at an elevation of 2,800 feet (853 m) in the W1/2 sec. 15, T. 24 N., R. 28 W., of the Seward Meridian. The coordinates are in the center of the spring system. The reporter visited the site in 1998.

Geologic setting

Geologic description

Straight Creek Springs consist of a very distinctive, north-south trending, 400-meter-long line of more than a dozen active springs, each containing conspicuous coatings and replacements of brilliant orange limonite and light gray, bleached, silicrete crusts up to 3 centimeters thick. The conspicuous orange-light gray colored springs occur immediately below the contact between the black shale-rich section of the Ordovician-Lower Silurian, Post River Formation and the mid to Late Silurian Terra Cotta Mountains Sandstone, both of lower Paleozoic age (Churkin and Carter, 1996; Bundtzen, Harris, and Gilbert, 1997). The springs may indicate a concealed mineralized source in the black shale section.
Herreid (1968) and T.K. Bundtzen and G.M. Laird (written communications, 1998) report that samples of silicrete-limonite material from two of the springs contain up to 125 ppm copper, 270 ppm zinc, 400 ppm nickel, and 10 ppm molybdenum.
Geologic map unit (-154.390235835517, 62.1693658329594)
Mineral deposit model Unknown; anomalous values are apparently derived from Ordovician-Silurian black shale section.
Age of mineralization Quaternary.
Alteration of deposit Silcrete-limonite.

Production and reserves

Workings or exploration The Straight Creek Springs were first described by Herreid (1968). Herreid (1968) and T.K. Bundtzen and G.M. Laird (written communication, 1998) report that samples of silicrete-limonite material from three of the springs contain up to 125 ppm copper, 270 ppm zinc, 400 ppm nickel, and 10 ppm molybdenum.
Indication of production None
Reserve estimates None.

Additional comments

The gossan occurs in the same stratigraphic position as exists in the Crash (MG049) and Dahl (MG053) prospects in the 'Farewell mineral belt'.

References