Jeff and Russell Prospect, Juneau Mining District, Juneau, Alaska, USAi
Regional Level Types | |
---|---|
Jeff and Russell Prospect | Prospect |
Juneau Mining District | Mining District |
Juneau | City Borough |
Alaska | State |
USA | Country |
This page is currently not sponsored. Click here to sponsor this page.
Latitude & Longitude (WGS84):
58° 18' 56'' North , 134° 22' 26'' West
Latitude & Longitude (decimal):
Type:
Köppen climate type:
Nearest Settlements:
Place | Population | Distance |
---|---|---|
Juneau | 32,756 (2017) | 3.1km |
Mindat Locality ID:
198209
Long-form identifier:
mindat:1:2:198209:4
GUID (UUID V4):
d37dcfcb-7502-4a58-80c5-a7eeb4fdf684
Location: The Jeff and Russell prospect is at an elevation of approximately 1000 feet on the north side of Gold Creek. It is 1 mile southeast of Mt. Juneau and 1/4 northeast of Ebner Falls, in the SE1/4NE1/4 section 13, T. 41 S., R. 67 E. of the Copper River Meridian. The location is accurate.
Geology: The Jeff and Russell prospect was discovered in 1930 and was developed by a 2,630-foot adit and 1,080 feet of crosscuts. This area was explored extensively by Echo Bay Mines Ltd. from the mid-1980's through the 1990's. The deposit consists of quartz veins near the contact between black phyllite and felsic phyllite, greenstone, and metagabbro (Redman and others, 1989). The veins contain pyrrhotite. U.S. Bureau of Mines samples contained up to 10.1 ppm gold (Redman and others, 1989). This prospect is in the Juneau Gold Belt, which consists of more than 200 gold-quartz-vein deposits that have produced nearly 7 million ounces of gold. These gold-bearing mesothermal quartz vein systems form a zone 160 km long by 5 to 8 km wide along the western margin of the Coast Mountains. The vein systems are in or near shear zones adjacent to west-verging, mid-Cretaceous thrust faults. The veins are hosted by diverse, variably metamorphosed, sedimentary, volcanic, and intrusive rocks. From the Coast Mountains batholith westward, the host rocks include mixed metasedimentary and metavolcanic sequences of Carboniferous and older, Permian and Triassic, and Jurassic-Cretaceous age. The sequences are juxtaposed along mid-Cretaceous thrust faults (Miller and others, 1994). The sequences are intruded by mid-Cretaceous to middle Eocene plutons, mainly diorite, tonalite, granodiorite, quartz monzonite, and granite. Sheetlike tonalite plutons emplaced just east of the Juneau Gold Belt and undeformed granite and granodiorite bodies that are emplaced farther to the east are between 55 and 48 Ma (Gehrels and others, 1991). The structural grain of the belt is defined by northwest-striking, moderately to steeply northeast-dipping, penetrative foliation that developed between Cretaceous and Eocene time (Miller and others, 1994). The majority of the veins in the Juneau Gold Belt strike northwest. Isotopic dates indicate that the auriferous veins in the Juneau Gold Belt formed between 56 and 55 Ma (Miller and others, 1994; Goldfarb and others, 1997).
Workings: The Jeff and Russell prospect was discovered in 1930 and was developed by a 2,630-foot adit and 1,080 feet of crosscuts.
Age: Isotopic dates indicate that the auriferous veins in the Juneau Gold Belt formed between 56 and 55 Ma (Miller and others, 1994; Goldfarb and others, 1997).
Commodities (Major) - Au
Development Status: None
Deposit Model: Low-sulfide Au-quartz vein (Cox and Singer, 1986; model 36a)
Select Mineral List Type
Standard Detailed Gallery Strunz Chemical ElementsCommodity List
This is a list of exploitable or exploited mineral commodities recorded at this locality.Mineral List
2 valid minerals.
Detailed Mineral List:
ⓘ Pyrrhotite Formula: Fe1-xS |
ⓘ Quartz Formula: SiO2 |
Gallery:
List of minerals arranged by Strunz 10th Edition classification
Group 2 - Sulphides and Sulfosalts | |||
---|---|---|---|
ⓘ | Pyrrhotite | 2.CC.10 | Fe1-xS |
Group 4 - Oxides and Hydroxides | |||
ⓘ | Quartz | 4.DA.05 | SiO2 |
List of minerals for each chemical element
O | Oxygen | |
---|---|---|
O | ⓘ Quartz | SiO2 |
Si | Silicon | |
Si | ⓘ Quartz | SiO2 |
S | Sulfur | |
S | ⓘ Pyrrhotite | Fe1-xS |
Fe | Iron | |
Fe | ⓘ Pyrrhotite | Fe1-xS |
Other Databases
Link to USGS - Alaska: | JU148 |
---|
Other Regions, Features and Areas containing this locality
This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to
visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders
for access and that you are aware of all safety precautions necessary.