Big Springs Mine (Sammy Creek; Mac Ridge; Mesona claim; Jack Creek project; Bull Run Mine), Independence Mountains Mining District, Elko County, Nevada, USAi
This page is currently not sponsored. Click here to sponsor this page.
Latitude & Longitude (WGS84):
41° 33' 37'' North , 115° 58' 32'' West
Latitude & Longitude (decimal):
Type:
Köppen climate type:
Nearest Settlements:
Place | Population | Distance |
---|---|---|
Owyhee | 953 (2011) | 44.2km |
Mindat Locality ID:
41210
Long-form identifier:
mindat:1:2:41210:1
GUID (UUID V4):
22a2ef8b-c087-4d15-a3a7-9195733ac6dd
The Big Springs Mine is composed of seven deposits developed by Freeport-McMoran Gold Co. (later Independence Mining Co., now Anglo Gold): Mac Ridge, M242936; North Sammy Creek, W700398; South Sammy Creek, W700399; 701 deposit, 131 deposit, 401 deposit, and 601 deposit.
Structure: Deformation related to the Antler Orogeny is the earliest tectonic event recorded in the Big Springs rocks, during which siliceous western assemblage rocks were emplaced over eastern assemblage carbonate and siltstone along the Roberts Mountain thrust fault. Compressional deformation of the Sonoma Orogeny occurred in the late Permian, during which the foredeep accumulated Schoonover Sequence was thrust over both the allochthonous western and autochthonous eastern assemblage rocks. Sonoma tectonism in the Big Springs area is evidenced by SE-verging overturned folds and imbricate thrust faults, all of which have been cut by later normal faults. A strong N75W fabric is manifested in folds and shears throughout the Independence Range and may be related to the Wells fault. This structural zone may have been reactiviated during the formation of the NW-striking Northern Nevada Rift Zone and Basin and Range extensional faulting. Deposits are structurally controlled at intersections of NE-trending and E-W-trending fault zones and fold axes. The E-W structure is part of a large ore-controlling shear zone that also truncates the northern mineralized zone at Big Springs. Many of the dikes occur along the NE-trending and E-W-trending fault intersections. A strong N75W fabric is manifested in folds and shears throughout the Independence Range and may be related to the Wells fault. This structural zone may have been reactiviated during the formation of the NW-striking Northern nevada Rift Zone and Basin and Range extensional faulting.
Alteration: Propylitic alteration is common throughout the volcanic rocks of the Dorsey Creek member. Gold mineralization occurs locally when the propylitically altered rocks are overprinted by quartz-sericite-pyrite-dolomite alteration
Tectonics: Antler foredeep basin
Commodity: Ore Materials: gold Gangue Materials: pyrite, marcasite,arsenopyrite, arsenical pyrite, sphalerite, chalcopyrite, stibnite
Deposit: The Big Springs mine consists of seven distinct deposits (Mac Ridge, North Sammy Creek, South Sammy Creek, 701 deposit, 131 deposit, 401 deposit, and 601 deposit) plus many additional resource areas of anomalous gold mineralization which were not mined. The deposits are characterized by disseminated, near-surface gold mineralization within 400 feet of the surface. Mineralization is structurally controlled and occurs primarily in allochthonous rocks of the Dorsey Creek and Mikes Creek members of the Schoonover Sequence. Host rocks include thin-bedded to cherty argillite, chert, conglomerate, siltstone, arenite, massive limestone, and fossiliferous limestone. Deposits are structurally controlled at intersections of NE-trending and E-W-trending fault zones and fold axes. The E-W structure is part of a large ore-controlling shear zone that also truncates the northern mineralized zone at Big Springs.
Deposit type: Sediment-hosted Au
Development: The area was first explored in the early 1980s by Freeport- McMoRan Gold Company. Extensive drilling, mapping, sampling, and construction of access roads were completed by Freeport by 1982. Mining of the Big Springs deposit was initiated by a joint venture between Freeport- McMoRan Gold Company (later Independence Mining Company) and Bull Run Gold Mines, Ltd. The mine was placed into production in September, 1987 and was fully operational by October, 1987. Initial production was from heap-leaching oxidized ore, but second phase construction provided a fluid-bed roasting system and conventional ore-milling facilities. Initially, Freeport planned to process 400,000 tons/year from three deposits at Big Springs to produce about 60,000 oz/year gold. The deposit was mined out in 1994, having produced a total of 386,000 troy ounces of gold from seven separate deposits on the property. Most of the gold was contained in refractory sulfide ore requiring a pre-oxidizing roasting method to enable conventional CIL recovery. Big Springs Project. In 2004, Gateway Gold Corp. continued work on its Big Springs project. A new geological model was developed based on the results of last year?s drilling and the company expects drilling this year will validate the model. In 2006, Gateway Gold Corp. announced that based on recent drill results at the Big Springs Project, resources aggregate 914,000 tons grading 0.345 ounces of gold per ton inferred using a 0.2 opt Au cutoff. (was 904,200 tons grading 0.288 ounces of gold per ton measured+indicated prior to the new round of drilling.)
Geology: The deposits occur primarily in allochthonous rocks of the Devonian to Permian Schoonover Sequence, which are cut by diorite and quartz monzonite intrusives which also host ore.
Ore(s): Mineralization at Big Springs was controlled by an E-W shear zone that also truncates the northern mineralized zone .Ore deposits are localized at intersections of NE-trending faults with this E-W-trending fault zone and fold axes.
Select Mineral List Type
Standard Detailed Gallery Strunz Chemical ElementsCommodity List
This is a list of exploitable or exploited mineral commodities recorded from this region.Mineral List
Mineral list contains entries from the region specified including sub-localities11 valid minerals.
Rock Types Recorded
Note: data is currently VERY limited. Please bear with us while we work towards adding this information!
Rock list contains entries from the region specified including sub-localities
Select Rock List Type
Alphabetical List Tree DiagramDetailed Mineral List:
ⓘ Arsenopyrite Formula: FeAsS |
ⓘ Baryte Formula: BaSO4 |
ⓘ Chalcopyrite Formula: CuFeS2 |
ⓘ Goethite Formula: α-Fe3+O(OH) |
ⓘ Gold Formula: Au Localities: Big Springs Mine (Sammy Creek; Mac Ridge; Mesona claim; Jack Creek project; Bull Run Mine), Independence Mountains Mining District, Elko County, Nevada, USA Mac Ridge Deposit, Big Springs Mine (Sammy Creek; Mac Ridge; Mesona claim; Jack Creek project; Bull Run Mine), Independence Mountains Mining District, Elko County, Nevada, USA |
ⓘ Marcasite Formula: FeS2 |
ⓘ Pyrite Formula: FeS2 |
ⓘ Rutile Formula: TiO2 |
ⓘ Sphalerite Formula: ZnS |
ⓘ Stibnite Formula: Sb2S3 |
ⓘ 'Tetrahedrite Subgroup' Formula: Cu6(Cu4C2+2)Sb4S12S |
ⓘ Zircon Formula: Zr(SiO4) |
Gallery:
List of minerals arranged by Strunz 10th Edition classification
Group 1 - Elements | |||
---|---|---|---|
ⓘ | Gold | 1.AA.05 | Au |
Group 2 - Sulphides and Sulfosalts | |||
ⓘ | Sphalerite | 2.CB.05a | ZnS |
ⓘ | Chalcopyrite | 2.CB.10a | CuFeS2 |
ⓘ | Stibnite | 2.DB.05 | Sb2S3 |
ⓘ | Pyrite | 2.EB.05a | FeS2 |
ⓘ | Marcasite | 2.EB.10a | FeS2 |
ⓘ | Arsenopyrite | 2.EB.20 | FeAsS |
ⓘ | 'Tetrahedrite Subgroup' | 2.GB.05 | Cu6(Cu4C2+2)Sb4S12S |
Group 4 - Oxides and Hydroxides | |||
ⓘ | Goethite | 4.00. | α-Fe3+O(OH) |
ⓘ | Rutile | 4.DB.05 | TiO2 |
Group 7 - Sulphates, Chromates, Molybdates and Tungstates | |||
ⓘ | Baryte | 7.AD.35 | BaSO4 |
Group 9 - Silicates | |||
ⓘ | Zircon | 9.AD.30 | Zr(SiO4) |
List of minerals for each chemical element
H | Hydrogen | |
---|---|---|
H | ⓘ Goethite | α-Fe3+O(OH) |
O | Oxygen | |
O | ⓘ Baryte | BaSO4 |
O | ⓘ Goethite | α-Fe3+O(OH) |
O | ⓘ Rutile | TiO2 |
O | ⓘ Zircon | Zr(SiO4) |
Si | Silicon | |
Si | ⓘ Zircon | Zr(SiO4) |
S | Sulfur | |
S | ⓘ Arsenopyrite | FeAsS |
S | ⓘ Baryte | BaSO4 |
S | ⓘ Chalcopyrite | CuFeS2 |
S | ⓘ Marcasite | FeS2 |
S | ⓘ Pyrite | FeS2 |
S | ⓘ Sphalerite | ZnS |
S | ⓘ Stibnite | Sb2S3 |
S | ⓘ Tetrahedrite Subgroup | Cu6(Cu4C22+)Sb4S12S |
Ti | Titanium | |
Ti | ⓘ Rutile | TiO2 |
Fe | Iron | |
Fe | ⓘ Arsenopyrite | FeAsS |
Fe | ⓘ Chalcopyrite | CuFeS2 |
Fe | ⓘ Goethite | α-Fe3+O(OH) |
Fe | ⓘ Marcasite | FeS2 |
Fe | ⓘ Pyrite | FeS2 |
Cu | Copper | |
Cu | ⓘ Chalcopyrite | CuFeS2 |
Cu | ⓘ Tetrahedrite Subgroup | Cu6(Cu4C22+)Sb4S12S |
Zn | Zinc | |
Zn | ⓘ Sphalerite | ZnS |
As | Arsenic | |
As | ⓘ Arsenopyrite | FeAsS |
Zr | Zirconium | |
Zr | ⓘ Zircon | Zr(SiO4) |
Sb | Antimony | |
Sb | ⓘ Stibnite | Sb2S3 |
Sb | ⓘ Tetrahedrite Subgroup | Cu6(Cu4C22+)Sb4S12S |
Ba | Barium | |
Ba | ⓘ Baryte | BaSO4 |
Au | Gold | |
Au | ⓘ Gold | Au |
Other Databases
Link to USGS MRDS: | 10310525 |
---|
Localities in this Region
- Nevada
- Elko County
- Independence Mountains Mining District
- Big Springs Mine (Sammy Creek; Mac Ridge; Mesona claim; Jack Creek project; Bull Run Mine)
- Independence Mountains Mining District
- Elko County
Other Regions, Features and Areas containing this locality
North America PlateTectonic Plate
- Antler Foreland BasinBasin
- Basin and Range BasinsBasin
- Copper–Bull Run–Elko–Indian Wells BasinBasin
- Mojave DomainDomain
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.
References
Quick NavTopCommoditiesMineral ListRock TypesOther DatabasesLocalities in RegionOther RegionsReferences