Abstract: Mineral Resources in Southwest Pacific

A. John Halunen

Onshore exploration and exploitation of mineral deposits in the southwest Pacific is now under way for copper and associated metals, nickel, gold, phosphate, and petroleum. A major copper mine on Bougainville, Papua New Guinea, has been in operation several years and a second major disseminated copper deposit is now under development at Namosi, Viti Levu, Fiji. Several gold mines have been operating in the region, particularly at Fiji and the Solomon Islands. Nickel production has been the economic mainstay for New Caledonia. Onshore petroleum exploratory drilling commenced in early 1978 on Tongatapu, Tonga, and preliminary results should be available by mid-year.

Offshore petroleum exploration is planned following the evaluation of the present effort in Tonga. In Bligh Water, Fiji, a concession has been taken to determine the depth to the Curie isotherm from the extensive magnetic data in the area. Following this thermal-maturation study exploratory drilling of apparent reef structures is planned.

A large manganese nodule deposit has been discovered in the Cook Islands. Although the concentration of nodules per unit area is very high, the copper-nickel-cobalt content appears to be generally less than 1% making this nodule field economically noncompetitive with other deposits. Additional work is planned for better delineation of the extent and grade of this deposit. The search for manganese nodules continues in Western Samoa, Tonga, the Solomon Islands, and Gilbert Island.

Studies of metalliferous sediments are under way on the Fiji Plateau and Lau basin as well as in the active volcanic arcs of the New Hebrides and Tonga.

Recent interest in the precious red coral industry has resulted in commencement of a search for this "mineral" in the Cook Islands, Western Samoa, and Tonga.

AAPG Search and Discovery Article #90962©1978 AAPG 2nd Circum-Pacific Energy and Minerals Resource Conference, Honolulu, Hawaii