Cook Islands Seabed Minerals Authority
Runanga Takere Moana


Our Journey


Exploration history

Seabed minerals explorations within the EEZ of the Cook Islands were reported to have been first carried out by the US and USSR research vessels in the 1960s. These surveys were later picked up by other companies and consortia in the early 1970s and continued until the late 1980s that resulted in the discovery of significant manganese nodule resources. These early seabed mineral investigations were mainly focused on identifying mineral occurrences and understanding their mode of occurrence and the geological setting in which they occur. Apart from efforts to identify other mineral types such as metalliferous sediments, cobalt-rich crusts, phosphate and precious coral, manganese nodules was the chief target of seabed mineral prospecting in the offshore areas of the Cook Islands.

Early surveys were not carried out in a reasonably detailed and systematic manner hence manganese nodule resources could not be quantified. It was not until the Japan-SOPAC Cooperative Study that commenced in 1985 for twenty-one years that any serious attempt was made to estimate the manganese nodule resources within the Cook Islands’ EEZ. Four exploration cruises (i.e. in 1985, 1986, 1990 and 2000) were carried out in the Cook Islands as part of this programme. The 2000 survey was conducted in the central eastern part of the country’s EEZ.

The East-West Centre undertook a study in 1993 in conjunction with SOPAC and MMAJ based on all available data at the time. They concluded that more exploration is needed to define the resource and determine the most favourable area before a decision could be made to develop the resource. Further they noted that “…nodule mining in the Cook Islands if proven economically feasible is still at a minimum a decade or more in the future”

In a 1995 East-West Center economic feasibility study, 652,000 km2 of the Cook Islands EEZ, where nodule abundances are greater than 5 kg/m2, were estimated to contain 7,474,000,000 tons of nodules. These nodules were estimated to contain 32,541,000 tons of cobalt, 24,422,000 tons of nickel and 14,057,000 tons of copper. In addition, there is the prospect of rare earth minerals being located in the mud on the seabed floor.

A 1996 economic assessment by the Bechtel Corporation of San Francisco concluded that a nodule mining project for cobalt (Co) in the CIEEZ, given a large number of assumptions, would be feasible so long as the price of Co did not drop below US$16.75 per pound in April l996 dollars.

In 1998, an informative report by Stuart Kingan[2], a scientist resident in the Cook Islands, was prepared for the government, with the hope of attracting foreign investment in DSM exploration and mining. Since then, the progress of the developmental process in DSM in the Cook Islands has continued, but with varying degrees of activity.

In 2000, a Norwegian study building on the Bechtel study determined that the cobalt price then at $US15 per pound made investment in any DSM venture uneconomic.

Despite that setback, successive Cook Islands governments have been proactive, with the assistance of international partners, in taking the necessary steps to develop a national framework for the regulation of its nation’s future in deep sea mining within its EEZ.


Below are expeditions that have been carried out in Cook Island waters (EEZ) since the late 1970s:

research vessel & year of survey

survey area

surveyed commodity

RV Tangaroa (1974)

Rarotonga, Cook Islands

Manganese nodules

MV Ravakai (1976)

Area between Rarotonga and Penrhyn

Manganese nodules, Metalliferous sediment and Phosphate

RV Acheron (1977)

Southern Group, Cook Islands

Precious coral, Manganese nodules

RV Machias (1978)

Penrhyn and Samoa Basins, Nearshore waters of the Cook Islands

Manganese nodules and Precious Coral

RV Machias (1980)

Northern Cook Islands

Manganese nodules and Precious coral

RV Machias (1980)

East  of  Penrhyn  Island,  Penrhyn  Basin, Penrhyn, Manihiki, Nassau Islands

Manganese  Nodules,  Precious coral and Phosphate

RV Sonne (1980)

Aitutaki Passage

Manganese Nodules

RV Hakurei Maru (1980)

South Penrhyn Basin

Manganese Nodules

MV Ravakai (1983)

Slopes of Rakahaga and Manihiki Atoll

Precious Coral

RV Hakurei Maru (1983)

South Penrhyn Basin

Manganese Nodules

RV Hakurei Maru 2 (1985)

Western Penhryn Basin, eastern margin of the  Manihiki  plateau  and  the  North  of Penrhyn Island.

Manganese Nodules

HMNZS Tui (1986)

Manihiki Plateau and adjacent Southwest sea areas

Cobalt-rich crust, Manganese nodules

RV Hakurei Maru 2 (1986)

Western  edge  of  the  southern  Penhryn Basin (to the east of the Manihiki plateau)

Manganese Nodules

RV Moana Wave (1987)

Cook  Islands:  Suwarrow  trough,  eastern Manihiki Plateau, Rakahaga-Manihiki island area

Cobalt-rich crust and Metalliferous sediments

RV  Thomas  Washington (1987)

Northern Cook Islands and adjacent High Seas

Manganese nodules, Cobalt-rich crust, Deep sea sediment

RV Sonne (1990)

North-east edge of Manihiki Plateau

Complex of Volcanic Cones and mineral resources

RV Hakurei Maru 2 (1990)

Southern Cook Islands

Manganese Nodules

RV Hakurei Maru 2 (2000)

Central Coo Islands (i.e.    Southern Penrhyn Basin)

Manganese Nodules

RV Grinna (2019)

Central Cook Islands (CIIC-SR reserve area)

Manganese Nodules

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