Scientists have completed mapping a previously unsurveyed part New Zealand's Exclusive Economic Zone.
They used sonar mapping and other techniques to draw a picture of 38,000 square kilometres of ocean floor on Colville Ridge, located to the west of the Kermadec Islands.
They say a key finding was so-called hydrothermal alteration of the seafloor rocks.
That means dissolved elements have passed through them, so part of the area could hold metallic minerals such as copper and gold.
The study by NIWA's deepwater research ship Tangaroa has produced a seafloor map with a resolution 30 times better than the previous map, which had been compiled from satellite data.
