Abstract
An active submarine volcanic centre has been detected on the western flank of the Tonga-Kermadec ridge midway between the Tonga and Kermadec islands group. It has the form of an isolated cone about 1000 m high reaching to within 200 m of the sea surface. Activity of the volcanic centre was observed acoustically and visually (upwelling and discolouration of sea water over the seamount) several times during 1977–79.