Marmot upper basin Prospect, Hyder Mining District, Prince of Wales-Hyder Census Area, Alaska, USAi

Regional Level Types
Marmot upper basin Prospect	Prospect
Hyder Mining District	Mining District
Prince of Wales-Hyder Census Area	Census Area
Alaska	State
USA	Country

The Marmot group of 51 claims that were staked in 1969 covered all or parts of the old Jumbo (Banded Mountain) (BC021), Galena (BC022), and Edelweiss (BC023) prospects, which are described separately in this report. The Marmot upper basin prospect area was only recently exposed by retreat of glacial ice. The prospect was active in 1973. Site is in Misty Fiords National Monument.
Location: The Marmot upper basin prospect (Berg and others, 1977, p. 106) is in Section 26 on the southeast side of Banded Mountain at an elevation of about 4600 to 4750 feet. This location is accurate to within about a quarter of a mile.
Geology: The country rocks in the general area of this prospect (Berg and others, 1977, p. 15-18, 22; Koch, 1996) are banded variegated pelitic hornfels, phyllite, and fine-grained schist of the Jurassic or older Mesozoic Hazelton Group. The metasedimentary rocks are intruded by andesite dikes that may be apophyses of the Triassic Texas Creek Granodiorite, and by aplite dikes that may be apophyses of Eocene Hyder Quartz Monzonite. The mineral deposit (Berg and others, 1977, p. 100, 106, 110, 112; Elliott and Koch, 1981, p. 9, loc. 19) consists of a stockwork(?) of quartz [-calcite] veins up to about 3 feet thick in locally iron-stained dark pelitic hornfels of the Hazelton Group. The veins contain pyrite, chalcopyrite, molybdenite, and galena. The highest assay values reported from vein and hostrock samples collected by the U.S. Bureau of Mines in 1972 were 2000 ppm Mo, 5000 ppm Pb, 3000 ppm Cu, 150 ppm Ag, and 0.1 ppm Au. Lead-isotope studies of the galena at the Marmot upper basin prospect (Maas and others, 1995, p. 229-248) indicate that the deposit is Eocene in age, contemporaneous with emplacement of the Hyder Quartz Monzonite.
Workings: Highest assay values reported from veins and hostrock samples collected by U.S. Bureau of Mines in 1972 were 2000 ppm Mo, 5000 ppm Pb, 3000 ppm Cu, 150 ppm Ag, and 0.1 ppm Au.
Age: Lead-isotope studies of the galena at the Marmot upper basin prospect (Maas and others, 1995, p. 229-248) indicate that the deposit is Eocene in age, contemporaneous with emplacement of the Hyder Quartz Monzonite.
Alteration: Local intense iron staining

Commodities (Major) - Ag, Cu, Mo, Pb; (Minor) - Au, Zn
Development Status: None
Deposit Model: Polymetallic veins

Other Databases

Link to USGS - Alaska:	BC019

Other Regions, Features and Areas containing this locality

References