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ocean resources

Peter Herzig, left, and Mark Hannington investigating samples from massive sulphide deposits on a research cruise in the western Pacific.

The ocean floor is littered with hidden treasure including gold and other valuable metals that are in high demand on world markets. This is the undersea realm that most excites Peter Herzig, an economic geologist who supports responsible development of marine resources and who heads GEOMAR, one of the world's largest centres for ocean research, based in Kiel, Germany.

No one has yet managed, on a commercial basis, to mine the seafloor for precious metals, though Toronto-based Nautilus Minerals Inc. has come close. It is currently pursing a deal to develop the Solwara 1 gold deposit off the coast of Papua New Guinea, which Dr. Herzig first explored about a decade ago. The company (which is not connected to Dr. Herzig) now says the project is on hold while it seeks to resolve a contract dispute with the PNG government. Meanwhile, exploration licences have been granted to various countries interested in mining the central Pacific for its manganese nodules – potato-sized lumps of metal that are widely scattered throughout international waters.

This week, Dr. Herzig was in Toronto to lay out the risks and benefits of mining the ocean for its resources. He also sits on an expert panel currently assessing Canada's ocean science program. Dr. Herzig's strong connections with Canada began in 1988 when he was a postdoctoral fellow at the University of Toronto. He spoke with The Globe and Mail about the coming era of ocean resource development as well as the state of Canada's presence on and under the waves.

What's the attraction in undersea mining for gold?

Metal prices have increased considerably and there is growing demand from Asian markets. Even thought the deposits are not particularly large, the metal concentrations are extremely high and at current prices, the deposits are commercially viable.

What about the impact to the seafloor environment?

I think it's possible to do it in a sustainable way because the impact is focused only on the mining area.

How did the gold get there?

In volcanically dominated areas there are magma chambers that lie 2 or 3 kilometres below the seafloor. Seawater is pushed down into cracks near these chambers where it is heated to hundreds of degrees and chemically converted, becoming very acidic. As the water comes back up, it leeches gold, copper, zinc, indium (which is used to make flat-panel video screens), and other metals. At the seafloor the metals combine with sulphur and precipitate out of the water.

Where are the most attractive deposits located?

They are in the western to southwestern Pacific. That includes Papua New Guinea, Fiji, The Philippines, New Zealand, and also Tonga, where the government of South Korea has applied for a licence.

What do you say to people who argue that these deposits should be left alone?

My answer is that in a few decades we will have ten billion people on the planet and the pressure on the oceans for food, energy and resources will undoubtedly increase. We need to be able to reach a balance between the economic use of the oceans and the protection of marine ecosystems.

What about mining for manganese nodules?

That's more of an ethical question. These things took millions of years to form. Do we want to go and take them? Manganese-nodule mining would mean disturbing something like 200 square kilometres per year, so you can imagine what would happen to the central Pacific. This would greatly influence biological communities and I think it would be totally unacceptable with current technology.

What's your assessment of the state of ocean science in Canada?

It's not that visible and it's poor in terms of support. The people are excellent. The technology developed in Canada, such as ROPOS (Remotely Operated Platform for Ocean Science) is world class. But there was no host institution to run that, so it's faded from view. And research vessels have never been a strength of Canada, which means researchers here have to go elsewhere. Given that you have the longest coastline in the world and that claiming jurisdiction in the Arctic is a big issue for Canada, I would say there is a lot of room for improvement.

What do you recommend?

I have suggested that Canada set up an ocean research institute. It probably would need $100-million to start and an annual budget of $50-million. And it would need one or two research vessels. The Canadian government has ordered the construction of patrol vessels for the Arctic and the hope of all my Canadian colleagues is that some of those would become research vessels.

This interview has been condensed and edited.

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