Unnamed Occurrence (ARDF - MH284; northwest of the terminus of Chistochina Glacier), Chistochina Mining District, Southeast Fairbanks Census Area, Alaska, USAi

Regional Level Types
Unnamed Occurrence (ARDF - MH284; northwest of the terminus of Chistochina Glacier)	- not defined -
Chistochina Mining District	Mining District
Southeast Fairbanks Census Area	Census Area
Alaska	State
USA	Country

Location: This occurrence is northwest of the 1966 terminus of the Chistochina Glacier at an elevation of about 5,200 feet. The occurrence is in the SE1/4SE1/4 section 4, T. 20 S., R. 15 E., Fairbanks Meridian. It corresponds to locality 17 on figure 1 of Rose (1967)and locality 8 on figure 6 of Cobb (1979 [OFR 79-238]) and is approximately the same as locality 133 in table 2 of Nokleberg and others (1991). The location is accurate within 0.2 mile.
Geology: The rocks in this area are part of the Eagle Creek Formation of Early Permian age and consist of interlayered argillite and limestone (Nokleberg and others, 1991). The unit was mapped as Mankomen Formation by Rose (1967). Subsequently, the units were remapped as part of the Eagle Creek Formation, a member of the Mankomen Group (Richter and Dutro, 1975). The Eagle Creek argillite is extensively pyritized at the site. The pyritized argillite lies north of a body of Upper Triassic (?) ultramafic rock that is intruded by quartz monzonite of Mesozoic age (Rose, 1967). A grab sample of pyritic argillite contained 0.02 ounce of gold per ton and trace amounts of silver and zinc (Rose, 1967).
Workings: Geologic mapping and limited surface sampling.
Age: Post-Early Permian and probably Mesozoic, related to a nearby granodiorite intrusion.
Alteration: Pyritization of Lower Permian argillite.

Commodities (Major) - Au; (Minor) - Ag, Zn (?)
Development Status: None

Other Databases

Link to USGS - Alaska:	MH284

Other Regions, Features and Areas containing this locality

References