Kermadec Arc at 24.8°S

A large submarine volcano in the Northern Kermadec Arc, ~120 km N of Monowai, is known informally as Volcano 19 from a research cruise designation. The basaltic to basaltic andesite edifice contains a 2.5 x 3.5 km outer caldera and a 1.9-km-wide inner caldera on the west. A cone complex lies in the center of the outer caldera, east of the inner caldera. Hydrothermal fields are located near the summit of the cone complex and at the base of the southern wall of the western inner caldera. Large high-temperature chimney vents discharge clear fluids and black plumes.