Outer Melanesian Arc II - Melanesia Area

Eocene-Oligocene to late Miocene-Pliocene-Pleistocene Outer Melanesian magmatic arc and Melanesian borderlands in the Solomon Islands
Tract ID 009pCu7210
Country Fiji-Solomon Islands-Vanuatu
Commodity Cu
Study area name Southeast Asia and Melanesia
Tectonic setting island arc
Deposit type porphyry copper
Grade-tonnage model Porphyry copper, Cu-Au subtype (Singer and others, 2008)
Geologic age
Geologic feature age Eocene through Holocene
Generalized age Tertiary-Paleogene
Oldest rocks age 55.8Ma
Youngest rocks age 0Ma
Age range 55.8Ma
Identified Cu resources 6,900,000metric tons
Known prospects 24
Mean Cu (t/sq km) 419t/sq km
Map scales used 100K, 200K, 250K, 500K, 1M

Results of the assessment

Assessment date 2011
Estimators Jane M. Hammarstrom, Gilpin R. Robinson, Jr., Steve Ludington, Arthur A. Bookstrom
Assessment depth 1km
Quantitative assessment Yes

Estimated number of deposits

Number of deposits Confidence level
1 90%
5 50%
10 10%
10 5%
10 1%
Mean estimated deposits 5.23 ±3.21 (0.61%)
Probability of mean 0.32
Probability of no copper 0.07

Estimated deposit density

Known
deposits
Total
deposits
Area
(sq km)
Deposit density
per 100,000 sq km
3 8.23 38,180 22

Mean estimated tonnage

Copper 16,000,000
Molybdenum 92,000
Gold 1,200
Silver 5,100
Ore 3,200

Undiscovered copper resource

Confidence level 90% 50% 10% 5%
Tonnage 480,000 9,100,000 40,000,000 60,000,000

Economic analysis

Fraser country Papua New Guinea* (for Solomon Islands, Vanuatu, Fiji)
Fraser type 0.08%
Fraser high 0.92%
Typical cost 0%
High cost 1%
Infrastructure setting High cost
Comments on depth deep
Expected depth distribution
0 - 250m 0.1
250m - 500m 0.3
500m - 1km 0.6
Economically recoverable resources
Copper 7,000,000t
Molybdenum 30,000t
Gold 340t
Silver 2,300t
Probability no econ recoverable 0.61
Econ NPV 1,300x $1M
Exp dollars 13.15x $1M/100,000 sq km
Exp value class Low

Bibliographic references

General Hammarstrom and others (2013)
Economic Robinson and Menzie (2012)

Deposits and prospects associated with this tract

Name Type State Country Development Details
Fauro prospect Western Solomon Islands Occurrence Details
Hidden Valley prospect Guadalcanal Solomon Islands Occurrence Details
Tirua prospect Western Solomon Islands Prospect Details
Kule prospect Western Division Fiji Occurrence Details
Nathilenga prospect Western Division Fiji Occurrence Details
Nuku prospect Central Division Fiji Occurrence Details
Rama Creek prospect Central Division Fiji Occurrence Details
Savundrondro Creek prospect Northern Division Fiji Occurrence Details
Tawaravi Creek prospect Western Division Fiji Occurrence Details
Vunda prospect Western Division Fiji Occurrence Details
Wainivau prospect Western Division Fiji Occurrence Details
Koloula deposit Guadalcanal Solomon Islands Prospect Details
Ballyorlo prospect Western Solomon Islands Prospect Details
Kele prospect Western Solomon Islands Prospect Details
Mase prospect Western Solomon Islands Prospect Details
Mbetilonga prospect Guadalcanal Solomon Islands Prospect Details
Meriguna prospect Western Solomon Islands Prospect Details
Poha prospect Guadalcanal Solomon Islands Prospect Details
N Malakula area(?) prospect Melampa Vanuatu Prospect Details
Tuvatu prospect Western Division Fiji Prospect Details
Waivaka deposit Central Division Fiji Prospect Details
Namosi deposit Central Division Fiji Prospect Details
Waivaka Group Group Central Division Fiji Prospect Details