Deep Post Mine

Producer in Eureka county in Nevada, United States with commodities Gold, Silver, Arsenic

Sections on this page

Identification information
Geographic coordinates
Site location context
Geographic areas
Public Land Survey System information
Commodities
Materials information
Alteration
Mineral occurrence model information
Host and associated rocks
Nearby scientific data
Geologic structures
Ore body information
Controls for ore emplacement
Economic information about the deposit and operations
Mining district
Land status
Ownership information
Bibliographic references
General comments
Reporter information

Geologic information

Identification information

Deposit ID	10310437
MRDS ID	W700371
Record type	Site
Current site name	Deep Post Mine
Related records	10084949, 10125664

Comments on the site identification

This record includes information from MRDS record W700371 for the Post Deposit

Geographic coordinates

Geographic coordinates:	-116.34732, 40.97518 (WGS84)
Elevation	1700
Relative position	The mine area is located about 37 km (23 miles) northwest of the town of Carlin. UTM is to the area of the open pit mine from which underground workings have been driven.

Site location context

Political divisions (FIPS codes)

Eureka(county)

Nevada(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Rodeo Creek NE(quadrangle 1:24,000 scale)

Battle Mountain(quadrangle 1:100,000 scale)

Winnemucca(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Middle Humboldt(hydrologic unit)

Humboldt(hydrologic accounting unit)

Black Rock Desert-Humboldt(hydrologic subregion)

Great Basin(hydrologic region)

Geographic areas

Country	State	County
United States	Nevada	Eureka

Public Land Survey System information

Meridian	Township	Range	Section	Fraction	State
Mount Diablo	36N	50E	29, 20		Nevada

Commodities

Commodity	Importance
Gold	Primary
Silver	Secondary
Arsenic Critical	Secondary

Comments on the commodity information

Commodity Info: Au occurs as micron to submicron-sized particles associated with quartz and clays in the oxide zones and with pyrite and marcasite in the sulfide zones. Simple refractory ore in the lower portions of the lower Post/Betze orebody is characterized by silicification with kaolinite & 5-10% disseminated pyrite. Carbon found distal and probably unrelated to the orebodies. Increasing Au grades associated with increasing amounts of pyrite/marcasite.
Ore Materials: GOLD, AURIFEROUS PYRITE, ARSENIAN PYRITE, ARSENOPYRITE, MARCASITE
Gangue Materials: quartz, pyrite, orpiment, realgar, kaolinite, dickite, sericite, illite, alunite, barite, stibnite, goethite, hematite, jarosite, gypsum, calcite

Materials information

Materials	Type of material
Gold	Ore
Pyrite	Ore
Arsenopyrite	Ore
Marcasite	Ore
Pyrite	Ore
Orpiment	Ore
Realgar	Ore
Kaolinite	Ore
Dickite	Ore
Sericite	Ore
Illite	Ore
Alunite	Ore
Barite	Ore
Stibnite	Ore
Goethite	Ore
Hematite	Ore
Jarosite	Ore
Gypsum	Ore
Calcite	Ore
Quartz	Gangue

Alteration

(Local) Decarbonization; argillic and silicic hydrothermal; oxidation.

Mineral occurrence model information

Model code	173
USGS model code	26a.1
Deposit model name	Sediment-hosted Au
Mark3 model number	17

Host and associated rocks

Host or associated

Host

Rock type

Sedimentary Rock > Clastic Sedimentary Rock > Argillite

Rock unit name

VININI FM.

Stratigraphic age (youngest)	Ordovician

Host or associated

Host

Rock type

Sedimentary Rock > Chemical Sediment > Chert

Rock unit name

POPOVICH FM./RODEO CREEK UNIT

Stratigraphic age (youngest)	Devonian

Host or associated

Host

Rock type

Sedimentary Rock > Clastic Sedimentary Rock > Mudstone

Rock type qualifier

CALCAREOUS

Rock unit name

POPOVICH FORMATION

Stratigraphic age (youngest)	Devonian

Host or associated

Host

Rock type

Sedimentary Rock > Clastic Sedimentary Rock > Siltstone

Rock unit name

POPOVICH FORMATION

Stratigraphic age (youngest)	Devonian

Host or associated Host

Rock type Sedimentary Rock > Clastic Sedimentary Rock > Sandstone

Host or associated	Host
Rock type	Sedimentary Rock > Clastic Sedimentary Rock > Sandstone

Host or associated

Host

Rock type

Sedimentary Rock > Chemical Sediment > Chert

Rock unit name

ROBERTS MOUTAIN FM.

Stratigraphic age (youngest)	Early Devonian
Stratigraphic age (oldest)	Wenlock

Host or associated

Host

Rock type

Sedimentary Rock > Carbonate > Limestone

Rock unit name

ROBERTS MOUTAIN FM.

Stratigraphic age (youngest)	Early Devonian
Stratigraphic age (oldest)	Wenlock

Host or associated

Associated

Rock type

Plutonic Rock > Mafic Intrusive Rock > Diorite

Rock unit name

GOLDSTRIKE STOCK

Stratigraphic age (youngest)	Late Jurassic
Chronological age	158

Host or associated

Associated

Rock type

Plutonic Rock > Granitoid > Granodiorite

Rock unit name

GOLDSTRIKE STOCK

Stratigraphic age (youngest)	Late Jurassic
Chronological age	158

Host or associated

Associated

Rock type

Plutonic Rock > Granitoid > Quartz Monzonite

Stratigraphic age (youngest)	Late Jurassic
Chronological age	158

Host or associated Associated

Rock type Plutonic Rock > Porphyry

Rock type qualifier BIOTITE MONZONITE

Stratigraphic age (youngest) Middle Eocene

Chronological age 39

Host or associated

Associated

Rock type

Volcanic Rock (Aphanitic) > Felsic Volcanic Rock > Latite

Rock unit name

LATITE SILL

Stratigraphic age (youngest)	Middle Eocene
Chronological age	39

Host or associated

Associated

Rock type

Plutonic Rock > Mafic Intrusive Rock > Diorite

Rock unit name

DIORITE SILL

Stratigraphic age (youngest)	Jurassic

Nearby scientific data

(1)	Slope Assemblage - Calcareous shale, siltstone, chert, quartzite, and greenstone	ListMap

Economic information

Geologic structures

Type of structure	Regional
Structure description	ROBERTS MOUNTAIN THRUST
Type of structure	Local
Structure description	N-NNW-TRENDING ZONE CONSIDERED MAIN HYDROTHERMAL CONDUIT; NNW TO N, AND NE-STRIKING FAULTS

Ore body information

General form STRATIFORM (APPROXIMATELY)

General form	STRATIFORM (APPROXIMATELY)

Controls for ore emplacement

STRUCTURALLY CONTROLLED NEAR SOUTHERN TERMINUS; PENETRATIVE FARTHER NORTH. HIGH ANGLE FAULTS CONTROL HIGHER GRADE AU. IMBRICATE THRUSTS RELATED TO ROBERTS MT. THRUST OR LATER EVENT INFLUENCED ORE LOCALIZATION. OXIDE ORE GENERALLY OCCURS IN VININI FM.(OR NEWMONT'S RODEO CREEK UNIT); REFRACTORY SULFIDE ORE TYPICALLY OCCURS IN POPOVICH & ROBERTS MT. FORMATIONS. PLUTONIC ROCKS OFTEN ACTED AS DAMS TO MINERALIZING FLUIDS.

Comments on the geologic information

AREHART, FOLAND, ET AL. (1993, LATEST PUB. ON THIS DEPOSIT) GIVES AGE OF MINERALIZATION AS 117 MA. OTHER POSSIBLE AGES OF MINERALIZATION ARE: 36-37 MA, 39 MA, OR 158 MA. THE LOWER POST, BETZE, AND DEEP POST DEPOSITS LIE BENEATH THE POST DEPOSIT AND SPACIALLY DISTINCT FROM POST. POST LIES ON THE UPPER PLATE OF THE ROBERTS MOUNTAIN THRUST; BETZE & LOWER POST ARE IN THE LOWER PLATE OF THIS THRUST. LOWER POST AND BETZE ARE A SINGLE OREBODY (AREHART ET AL). ASSOCIATED IGNEOUS ROCKS, SHOWN ABOVE, ALSO HOST ORE IN THE POST DEPOSIT. NNW TO N FAULTS AND SOME NE FAULTS SHOW MOVEMENT AFTER ORE FORMATION. FAULTING CAUSED BRECCIATION AND PREPARATION FOR HIGHER GRADE MINERALIZATION. COLLAPSE & HYDROTHERMAL BRECCIAS OF ABOVE-NAMED HOST ROCKS ALSO HOST ORE. MINOR AU MINERALIZATION FOUND IN GOLDSTRIKE INTRUSIVE, USUALLY ALONG FAULTS OR JOINTS. AMERICAN BARRICK AND NEWMONT USE DIFFERENT NAMES FOR THE SAME UNITS (SUCH AS ROBERTS MOUNTAIN FM.).

Economic information about the deposit and operations

Operation type	Surface
Development status	Producer
Commodity type	Metallic
Deposit size	Large
Significant	Yes
Discovery year	1982
Discoverer	Geologists working for Western States Minerals Corporation
Year of first production	1986

Mining district

District name	Lynn District
District name	Goldstrike subdistrict
District name	Carlin Trend

Land status

Ownership category	Private
Ownership category	BLM Administrative Area
Area name	Elko Administrative District

Ownership information

Type Owner-Operator

Owner Barrick Gold in cooperation with Newmont Gold

Year 2006

Type	Owner-Operator
Owner	Barrick Gold in cooperation with Newmont Gold
Year	2006

Comments on the workings information

OPEN PIT

Comments on other economic factors

The pre-mine resource for the Deep Post deposit was listed in 2002 as 4 million ounces of gold.

Comments on development

Anomalous gold detected in outcrops; orebody encountered in first drill hole. Western States Minerals commenced mining in 1986, and sold the Post deposit to Barrick Goldstrike in January 1987. Lower Post was discovered by deep drilling in 1987. Further drilling in 1987 defined the Betze orebody, "the largest deposit discovered to date in the Carlin trend" (Lauha & Bettles, 1993). The Post orebody is mined by Barrick Goldstrike as a major ore source for the Goldstrike mine processing facilities. Most reserves are mined from Betze pit, which was expected to reach depth of approx. 1,600 feet, with a stripping ratio of 1:7. Refractory ore is processed by autoclave , which is expected to reach a daily capacity of 15,000 tons/day in 1993. The Newmont portion of Lower Post will be mined sometime after 1993. ; econ.com: cyanidation relatively unsuccessful on refratory sufide ore, so barrick processes such ores by roasting or pressure oxidation, then cyanidation.

Reference information

Bibliographic references

Deposit

Rocky Mountain Pay Dirt, March, 1988, p. 4a-5a.
Deposit

Rocky Mountain Pay Dirt, June, 1988, p. 3a.
Deposit

Knutsen, G. C., Bettles, K. H., Sulfrian, C. E., and Zimmerman, C. J., 1987, Discovery and geology of the Post Gold Deposit, Eureka County, Nevada: Society of Mining Engineers Preprint Number 87-86, 6 p.
Deposit

Albino, George, 1993 Oral Communication, July 22, 1993, Reno, NV
Deposit

Arehart, G.B., Foland, K.A., Naeser, C.W., and Kesler, S.E., 1993, 40Ar/39Ar, K/Ar, and Fission Track Geochronology of Sediment-Hosted Disseminated Gold Deposits at Post-Betze, Carlin Trend, Northeastern Nevada; Economic Geology, v. 88, no. 3, P. 622-646
Deposit

Bonham, H.L., 1988, Bulk-Mineable Precious-Metal Deposits, in, The Nevada Mineral Industry, 1987, Nevada Bureau of Mines and Geology MI-1987
Deposit

Bonham, H.L., 1986, Bulk-Mineable Precious-Metal Deposits and Prospects, Nevada Bureau of Mines and Geology Map 91
Deposit

Bonham, H.L., 1991, Bulk-Mineable Precious-Metal Deposits and Prospects, Nevada Bureau of Mines and Geology Map 91, 3rd ed.
Deposit

Environmental Assessment, 1987, Nevada Bureau of Mines and Geology Files
Deposit

Nevada Bureau of Mines and Geology Mining District File 115, Numerous Press Clippings
Deposit

Lauha, E.A., and Bettles, K.H., 1993, A Geologic Comparison of the Post/Betze and Purple Vein Deposits of the Goldstrike and Meikle Mines, Nevada, SME Preprint 93-170, presented at SME Annual Meeting, Reno, NV, Feb. 15-18, 1993
Deposit

Bonham, H.L., and Hess, R.H., 1990, Bulk-Mineable Precious-Metal Deposits, in The Nevada Mineral Industry, 1989, Nevada Bureau of Mines and Geology MI-1989, p. 21
Deposit

Bonham, H.L., 1989, Bulk-Mineable Precious-Metal Deposits, in The Nevada Mineral Industry, 1988, Nevada Bureau of Mines and Geology MI-1988, p.21
Deposit

Arehart, G. B., Eldridge, C.S., Chryssoulis, S.L., Kesler, S.E., 1993, Ion Microprobe Determination of Sulfur Isotope Variations in Sulfides from the Post/Betze Sediment-Hosted Disseminated Gold Deposit, Nevada, USA, Geochimica et Cosmochimica Acta, v.57, pp.1505-1519
Deposit

Long, K.R., DeYoung, J.H., Jr., and Ludington, S.D., 1998, Database of significant deposits of gold, silver, copper, lead, and zinc in the United States; Part A, Database description and analysis; part B, Digital database: U.S. Geological Survey Open-File Report 98-206, 33 p., one 3.5 inch diskette.
Deposit

Thompson, Tommy, Teal, Lewis, and Meeuwig, Richard, editors, 2002, Gold Deposits of the Carlin Trend, NBMG Bulll. 111.
Deposit

Chris H. Clode, Steven R. Grusing, Ivan M. Johnston, and Dean G. Heitt, 2002, Geology of the Deep Star Gold Deposit, in Gold Deposits of the Carlin Trend, NBMG Bull. 111.
Deposit

LONG AND OTHERS, 1998

General comments

Subject category	Comment text
Deposit	The higher grade ore is generally found adjacent to faults and in crests of folds, below impermeable units. The deposit contains both sulfide and oxide ore. Lower Post and Betze are horizontally and vertically adjacent parts of the same orebody, discovered and then named separately. Betze is NW of and below Post; the Lower Post is directly below Post. Supergene alunite from Post has been K/Ar dated at 8.48 to 9.58 Ma (Arehart, cited in Lauha & Bettles). The Post orebody is oxide ore, hosted by Vinini Fm. The Lower Post/Betze ores are refractory, hosted by Popovich and to a lesser extent Roberts Mountains Formation. The secondary mineralization trend at Lower Post/Betze is N40-70E.

Subject category

Comment text

Deposit

The higher grade ore is generally found adjacent to faults and in crests of folds, below impermeable units. The deposit contains both sulfide and oxide ore. Lower Post and Betze are horizontally and vertically adjacent parts of the same orebody, discovered and then named separately. Betze is NW of and below Post; the Lower Post is directly below Post. Supergene alunite from Post has been K/Ar dated at 8.48 to 9.58 Ma (Arehart, cited in Lauha & Bettles). The Post orebody is oxide ore, hosted by Vinini Fm. The Lower Post/Betze ores are refractory, hosted by Popovich and to a lesser extent Roberts Mountains Formation. The secondary mineralization trend at Lower Post/Betze is N40-70E.

Reporter information

Type	Date	Name	Affiliation	Comment
Reporter	01-NOV-2004	LaPointe, D.D.	Nevada Bureau of Mines and Geology
Editor	01-SEP-2007	Schruben, Paul G.	U.S. Geological Survey	Converted from S&A FileMaker format to Oracle. Edit checks on rocks, units, and ages with Geolex search, and other fields.

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.

Maps centered on this site

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