Experts discuss seabed exploration

New Zealand experts have given their opinions on the opening up of 120,000 square kilometres of seabed for exploratory surveying of minerals in the Cook Islands.

Over the next three months, the Cook Islands will be receiving tenders from interested parties seeking to undertake exploratory surveying in the Exclusive Economic Zone.

Finance Minister Mark Brown said estimates placed the value of the seabed minerals in the range of billions of dollars.

Professor Jonathan Gardener from Victoria University Wellington said the big concern with this sort of mining is that no-one knows much about the biological community, or perhaps communities, living in this environment.

He said nodules tended to form over a long period of time in an environment that was relatively stable.

Thus, mining of nodules could disrupt what are believed to be old and stable biological communities.

“We don’t know how the biological communities will respond to this mining disturbance. We don’t know if they can recover, and if they do, at what rates.”

Gardener said large scale mining activities have the potential to change, over very long periods of time, biological communities that are part of the marine environment.

“The precautionary principle indicates that until we have a much better understanding of the impact of mining on such communities, then mining should not proceed, or should only proceed at small scales.”

As is often the case, he says scientists need more data to be able to judge the risks before mining activity begins.

Professor Barry Barton of the University of Waikato said the Cook Islands Government had done some good work.

“We have to remember that the technology here is new, the economic resources are little-known, and the environment is little-known too.”

Barton said there could be good progress made in getting important resource and environmental information in place, not only for specific projects, but for the Cook Islands marine areas in general.

“New Zealand’s experience shows that developing sound environmental science is important, and not always easy. Good baseline information should be an early priority.”

Dr Ian Graham from GNS Science commented on specific aspects of the seabed exploration and mining.

“Prospectors are interested in ferromanganese nodules - metal-rich concretions that form by direct precipitation from seawater.”

He said they occur in vast quantities in many parts of the deep ocean, and are sought for their metal content, particularly copper, nickel and cobalt.

Graham said miners are likely to use mainly non-invasive techniques such as sonar and photography to assess surface density and either dredging or piston coring to collect samples for analysis.

“There is no need for seismic or other deeply-penetrating geophysical techniques, since the deposits occur on, rather than beneath, the seafloor.”

Cook Islands Seabed Minerals Commissioner, Paul Lynch, previously told CI News that the Cook Islands would not be approving any tenders for exploration without properly weighing up the risks.

He said the government was committed to ensuring that the marine environment was not harmed in the process of exploration.