The great NZ land grab

Fancy a trip to the Challenger Plateau? Or the Three Kings Ridge?

They may sound unfamiliar but these vast sections of land are now officially part of New Zealand - it's just that they're underwater.

New Zealand, along with Australia and Brazil, is one of just three countries to be granted sovereign rights to its continental shelf by the United Nations.

We now have rights over 5.45 million sq km of our continental shelf - an area three times the size of France.

"We're huge, technically. If you look at it there's more than a square kilometre per person," said Dr Vaughan Stagpoole, marine geophysicist for GNS Science, the New Zealand institute that researches our geology and environment.

Stagpoole was one of a team of people including other scientists from GNS and Niwa and officials from the Ministry of Foreign Affairs and Trade who have worked since 1996 on the project of submitting a claim for our continental shelf to the United Nations.

By the end, their submission to the UN was 2600 pages long.

"We knew we would get something, it was just a case of putting the best argument forward," Stagpoole said.

The project included at least six months of surveying the seabed using sonar and seismic equipment on five ships including Niwa's RV Tangaroa.

The deepest part of our new territory is about 10,000m in the Kermadec Trench, dwarfing our tallest mountain, Aoraki Mount Cook (3754m). The shallowest is 250m in the Reinga Basin off the northwest of the North Island. (The Sky Tower is 328m tall.)

The seabed may contain valuable minerals or petroleum reserves.

An offshore oil well may represent an investment of $100 million which could generate billions of dollars in revenue for the country.

But Stagpoole said the new territory increased New Zealand's responsibility.

"Now that we have this territory there's also a commitment for New Zealand to manage it properly."

The success of our claim has now resulted in GNS helping other countries with their UN submissions.

So far they are offering consultancy advice to Malaysia, Brunei, Sri Lanka and the Philippines.