N.Z. SEABED SURVEY

Press, Volume CV, Issue 30998, 2 March 1966, Page 3

N.Z. SEABED SURVEY

(N'.Z. Press Association)

WELLINGTON, March 1.

A six-man team from the New Zealand Oceanographic Institute is at present at sea surveying the earth’s magnetic field in the Bay of Plenty.

The study is one of a series of five the institute has on its early 1966 programme.

The first, carried out last month, was a hydrological survey in the region northwest of North Cape. One of a number undertaken to complete the regional hydrology of New Zealand waters, the cruise involved measurements of temperature and salinity of sea water at all depths, an institute spokesman said today. The results obtained will be of considerable interest to marine scientists, fisheries and naval personnel. firstly because the distribution of temperature and salinity are of fundamental importance to marine life and. secondly, from them the ocean circulation and current patterns can be computed. Volcanic Centres

On the present cruise, the institute members hope to identify any submarine volcanic centres which occur in the Bay of Plenty area, even though they are not visible on the sea-bed. The nature of these structures, if they occur, can probably be determined by comparing their magnetic field with that around White Island, a known dormant volcano.

The third cruise, which will leave Auckland nn Saturday week, will be to obtain better

structural and geophysical information on the Lord Howe Rise, a submarine ridge extending in a south-east-north-west direction from New Zealand and occupying an important part of the Tasman Sea floor.

Geological History

It is the submarine equivalent of a mountain range some 250 nautical miles wide and some 1300 long. Its topography is buried under a thick blanket of sediments and its origin is closely related with the development and geological history of the Tasman and New Zealand land mass.

On a cruise starting from New Plymouth on March 27, five institute staff members will take the m.v. Taranui out to survey the depth and sediment of the continental shelf and slope off Raglan. This will complete a picture of the submarine topography and

sediments started some time ago. The last cruise, between April 1 and 5, will involve work off Taranaki and in the Cook Strait.