Porgera Mine

Producer in Papua New Guinea with commodities Gold, Silver, Copper, Lead, Zinc
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Alteration
  8. Host and associated rocks
  9. Nearby scientific data
  10. Geologic structures
  11. Ore body information
  12. Controls for ore emplacement
  13. Economic information about the deposit and operations
  14. Ownership information
  15. Reserves and resources
  16. Links to other databases
  17. Bibliographic references
  18. General comments
  19. Reporter information

Geologic information

Identification information

Deposit ID 10055079
MRDS ID RE00015
Record type Site
Current site name Porgera Mine

Geographic coordinates

Geographic coordinates: 145.08219, -5.46459 (WGS84)
Elevation 2500
Relative position FIVE KM WEST OF PORGERA TOWNSHIP, TWENTY-FIVE KM SOUTH OF LAGAIP FAULT ZONE, AND ONE HUNDRED AND THIRTY KM (80 MILES) WEST OF MOUNT HAGEN IN THE ENGA DISTRICT.

Site location context

Political divisions (FIPS codes)

Papua New Guinea(country)

Geographic areas

Country
Papua New Guinea

Comments on the location information

  • LAGAIP FAULT ZONE SEPARATES THE PAPAUAN PLATFORM FROM THE CENTRAL OROGENIC ZONE THAT FORMS THE MOUNTAINOUS SPINE OF NEW GUINEA AND MARKS THE ZONE OF INTERACTION BETWEEN THE AUSTRALIAN CONTINENTAL PLATE AND THE PACIFIC OCEAN PLATE.

Commodities

Commodity Importance
Gold Primary
Silver Primary
Copper Tertiary
Lead Tertiary
Zinc Critical Tertiary

Materials information

Materials Type of material
Chalcopyrite Ore
Galena Ore
Gold Ore
Marcasite Ore
Pyrite Ore
Silver Ore
Sphalerite Ore
Tetrahedrite Ore
Barite Gangue
Calcite Gangue
Chalcedony Gangue
Dolomite Gangue
Siderite Gangue

Alteration

  • (Local) Early Low Grade Propylitic Assemblages Of Chlorite And Calcite Overprinted By Phyllic Assemblages Of Sericite And Dolomite, Subordinate Quartz And Clay.

Analytical data

Result MORE THAN SIXTY PER CENT OF GOLD IS SUBMICROSCOPIC WITH ANHEDRAL BLEBS RARELY UP TO 8MM IN DIAMETER. SILVER CONTENT RANGES UP TO 50% WITH AN AVERAGE OF 10-30%. MORE THAN ONE TYPE OF REFRACTORY GOLD AND EXTREME VARIABILITY OF GOLD GRADE.

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite
    Stratigraphic age (youngest) Miocene
    Stratigraphic age (youngest) Miocene
    Stratigraphic age (youngest) Late Cretaceous
    Stratigraphic age (youngest) Late Cretaceous
  • Host or associated Associated
    Rock type Plutonic Rock > Mafic Intrusive Rock > Gabbro
  • Host or associated Associated
    Rock type Volcanic Rock (Aphanitic) > Intermediate Volcanic Rock > Andesite
  • Host or associated Associated
    Rock type Volcanic Rock (Aphanitic) > Mafic Volcanic Rock > Basalt
  • Host or associated Associated
    Rock type Plutonic Rock
    Rock unit name Porgera Intrusives
    Rock description Porgera Intrusives
  • Host or associated Host
    Rock type Sedimentary Rock > Clastic Sedimentary Rock
    Rock unit name Chim
    Rock description Chim
  • Host or associated Host
    Rock type Sedimentary Rock > Clastic Sedimentary Rock > Shale > Black Shale
  • Host or associated Host
    Rock type Sedimentary Rock > Clastic Sedimentary Rock > Sandstone

Nearby scientific data

(1) 145.08219, -5.46459

Economic information

Geologic structures

Type of structure Regional
Structure description East-Trending Steeply Dipping Roamane Fault. Extensive Zones Of Brecciation.
Type of structure Local
Structure description Thrusts And Steeply Dipping Faults, Fractures And Multiple Veins. Banded And Colloform Textures .

Ore body information

  • General form IRREGULAR
    Strike NORTH WEST
    Dip INTRUSIVE CONTACTS DIP GREATER THAN 45 DEGREES
    Plunge direction SEVERAL TIGHT FOLDS PLUNGE TO THE SOUTHEAST
    Width 7000M

Controls for ore emplacement

  • Intense Fracture Patterns Control The Shape And Distribution Of Intrusions And Microscopic Veining Which Localize Mineralization.

Comments on the geologic information

  • INTRUSIVE COMPLEX CONSISTS OF LARGE NUMBER OF SMALL, BASIC TO INTERMEDIATE STOCKS, SILLS, AND DIKES WHICH APPEAR ALIGNED AS A SERIES OF CONE SHEETS. SEMI-CIRCULAR STRUCTURAL CONTROL AND CIRCULAR AEROMAGNETIC ANOMALY SUGGESTS PRESENCE OF LARGE, DEEP-SEATED PLUTONIC BODY. RECENT INVESTIGATIONS HAVE IDENTIFIED FIVE MINERALIZATION TYPES THAT ARE SPATIALLY INDEPENDENT OF ANY PARTICULAR LITHOLOGIC UNIT (FLEMING ET AL.,1986)

Economic information about the deposit and operations

Development status Producer
Commodity type Metallic
Significant No
Discovery year 1933
Discoverer Alluvial Gold Was Originally Discovered In The Pogera River 1933-1939; Lodes Discovered By The Australian Bureau Of Mineral Resources 1967. (Cotton, 1975); (Fleming Et Al., 1986)

Ownership information

  • Type Owner
    Owner Mim 1/3, Renison Goldfields 1/3, Placer Development 1/3.

Reserves and resources

  • Type In-situ
    Estimate year 1984
    Total resources 76800000mt ore
    Commodity Subtype Grade units Group Importance Year
    Gold Au 3.8 g/mt Gold Major 1984

Comments on development

  • 1961 SYSTEMATIC EXPLORATION BEGAN. 1979-1987 EXTENSIVE EXPLORATION AND DRILLING BY PLACER (PNG) PTY. LTD., ON BEHALF OF PORGERA JOINT VENTURE (MT. ISA MINES LTD., RENISON GOLDFIELDS CONSOLIDATED LTD. AND PLACER)

Reference information

Bibliographic references

General comments

Subject category Comment text
Deposit THE PORGERA DEPOSIT REPRESENTS A COMPLEX HYDROTHERMAL GOLD BEARING QUARTZ-SULFIDE-CARBONATE-CHLORITE VEINING, SPATIALLY AND GENETICALLY RELATED TO A COMPLEX INTRUSIVE SUITE OF HORNBLENDE DIORITE AND OTHER PROPHYRITIC DIORITE UNITS, CONSISTING OF METER WIDE DIKES TO STOCKS AND SILLS TENS TO HUNDREDS OF METERS IN DIMENSION. ADULARIA AU-AG AND ASSOCIATED HOT SPRING AU-AG.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-MAR-1991 Moyer, Lorre A. (Marcus, S.M.) U.S. Geological Survey

Beyond USGS

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