The Campbell Plateau is a large submarine platform extending southward and eastward from the region of Stewart Island. The maximum east-west width of the Plateau, measured across the 750-fathom isobath, is about 570 miles, while the maximum north-south width is about 380 miles. Most of the Plateau lies between the 200- and 500-fathom isobaths, but it breaks surface in several places, forming the Bounty Islands, Antipodes Islands, Auckland Islands, and Campbell Island.
On its northern side the Campbell Plateau descends into the Bounty Trough, on its western side into the Tasman Basin, and on its south-eastern side into an extension of the South-west Pacific Basin. The slopes bounding the Plateau to the north and south-east are relatively gentle, but on the west the downward gradient is considerably steeper, and the edge of the Plateau better defined than in other sectors.
The surface of the Plateau is diversified by a number of banks, the most important being Discovery Bank, situated about 230 miles ENE of the Auckland Islands and rising to within 45 fathoms of the surface. These banks are probably the eroded remains of volcanoes that have been levelled off by the sea at low stands of sea level during the ice ages.
by Henry Moir Pantin, B.A.(CANTAB.), PH.D.(CANTAB.), New Zealand Oceanographic Institute, Department of Scientific and Industrial Research, Wellington.