Final seabed survey to determine New Zealand's continental shelf boundary

The research vessel Tangaroa will set off on 20 May for the final data-gathering phase of a $44 million project to map the outer limits of New Zealand's continental shelf.

The four-week voyage will survey the seabed over a large area to the east of the Chatham Islands, which are about 700km east of New Zealand.

Seismic survey equipment on Tangaroa has the ability to penetrate the sea floor to depths of up to 3km to determine sediment thickness and the shape of the seafloor - critical factors in determining the precise extent of New Zealand's legal continental shelf boundary.

In the area to be surveyed, the survey team expects to image extinct Ruapehu-sized volcanoes, ravines up to 1km deep, and sedimentary drift deposits up to 1km thick. Tangaroa will also dredge rocks from five seafloor sites 600km northeast of the Chatham Islands.

Analysis of the rocks, including measurements of their age, will help establish how far the New Zealand continent extends from the Chatham Rise. The ship will also be taking gravity and magnetic measurements of the seafloor.

The information will be used to support New Zealand's continental shelf submission to the United Nations, which is due to be tabled by 2009, says Land Information New Zealand (LINZ) Project Leader, Russell Turner.

"The New Zealand Continental Shelf Project is about drawing the boundary around the sovereign rights we exercise over the sea bed extending beyond the current 200 nautical mile limit or Exclusive Economic Zone (EEZ).

"The data collected from the marine surveys will assist us in presenting a very accurate case to the UN," says Russell Turner.

Under the United Nations Convention on the Law of the Sea (UNCLOS), which New Zealand ratified in 1996, countries must lodge submissions defining their outer shelf limits.

"This voyage of Tangaroa is the last of seven data-gathering voyages undertaken since 1996. The next phase of the project will focus on processing the data to provide the strongest possible backing for our submission."

LINZ has contracted scientific advisers Dr Ian Wright from NIWA (National Institute of Water and Atmospheric Research), Dr Bryan Davy and Dr Dan Barker from GNS (Institute of Geological and Nuclear Sciences) to provide expert help and analysis during the voyage.

Tangaroa is New Zealand's premier scientific research vessel. The 2280 tonne purpose-built vessel is equipped with laboratory space and specialist equipment. It will have a crew of 14 during the 30-day voyage, as well as 8 science and technical staff.

ENDS

For more information see the Continental Shelf section of the LINZ website or contact the following people:

Russell Turner
Ph: (04) 460 0588
Email: rturner@linz.govt.nz
Project Leader New Zealand Continental Shelf Project
Land Information New Zealand
PO Box 5501
WELLINGTON

Geoff Baird
Ph: (04) 386 0543
Email: g.baird@niwa.co.nz
Manager, Science Communication
National Institute of Water and Atmospheric Research Ltd
PO Box 14 901
WELLINGTON

John Callan
Communications Co-ordinator
Ph: (04) 570 4732
Email: j.callan@gns.cri.nz
Institute of Geological and Nuclear Sciences
PO Box 30 368
LOWER HUTT

Media liaison:

Judith Hamblyn
Ph : 04 498 3502
Email: jhamblyn@linz.govt.nz
Communications Adviser
Land Information New Zealand
PO Box 5501
WELLINGTON