Chathenda Creek

Prospect, Inactive

Alternative names

Johnson Creek

Commodities and mineralogy

Main commodities Au; Cu
Ore minerals chalcopyrite; marcasite; pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale NB
Quadrangle map, 1:63,360-scale A-2
Latitude 62.0788
Longitude -141.9257
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect is on the north bank of Chathenda Creek about 0.9 mile upstream from the mouth of Salt Creek and 1.2 miles downstream from Bonanza. The site is in the SW1/4 of section 34, T. 4 N., R. 19 E. of the Copper River Meridian. This is locality 39 of Richter and others (1975). Cobb and Richter (1980) included this prospect under the name 'Chathenda Cr.'. It is located to within a few hundred feet.

Geologic setting

Geologic description

This prospect consists of gold-bearing quartz-pyrite veins, some of which contain marcasite. The veins are in a zone up to 10 feet wide of mineralized, volcanic and diorite country rocks (Capps, 1916; Pilgrim, 1931, p. 66-68). The mineralized zone strikes N 65 W and dips 78 S. Gold values of 0.01 and 0.10 ounce of gold per ton were reported by Pilgrim (1931). A chip sample across 5 feet of limonite-stained, fine-grained, volcanic rock contained 1.5 parts per million (ppm) silver, 1,500 ppm chromium, 500 ppm copper, and 300 ppm lead (Richter and Matson, 1970 [OFR 70-275]). The host rocks are volcanic and volcaniclastic rocks of the Cretaceous, Chisana Formation (Richter and Jones, 1973). These volcanic rocks are intruded by the mid-Cretaceous, Chisana pluton about 1,000 feet north of the prospect. The Chisana pluton varies from clinopyroxene diorite to monzonite and has been dated by K/Ar methods as 110 +/- 3.0 Ma (Richter, Lanphere, and Matson, 1975).
Geologic map unit (-141.927827781065, 62.0784337281245)
Mineral deposit model Polymetallic veins (Cox and Singer, 1986; model 22c)
Mineral deposit model number 22c
Age of mineralization Mid-Cretaceous? The deposit may be related to emplacement of the Chisana pluton which has a K/Ar date of 110 +/- 3.0 Ma (Richter, Lanphere, and Matson, 1975).
Alteration of deposit Pyrite and quartz veining and replacement(?); oxidation has produced abundant iron-staining.

Production and reserves

Workings or exploration There are open cuts and two short adits in this area (Capps, 1916). A number of small gold-bearing quartz-pyrite lodes occur in mineralized volcanic country rock of the Cretaceous, Chisana Formation on the north side of Chathenda Creek (also see NB092 and NB093). By 1940 a large group of claims had been staked in this area but exploration, including trenches and some short adits, was unsuccessful.
Indication of production None

Additional comments

The prospect is in the Wrangell-St. Elias National Preserve.