The eighth continent is almost entirely underwater

Zealandia is 94% underwater, a continent hidden beneath the waves.

Its highest ground is New Zealand's Southern Alps, pushed up by the Alpine Fault.

Far to the east, the Chatham Islands are another piece of it above the sea.

In all it covers about 4,900,000 square kilometres, nearly the size of Australia.

New Zealand is the largest part still above sea level.

New Caledonia and its islands are another.

Seafloor spreading split it from Australia 52 million years ago.

The same movement squeezed the Alpine Fault and lifted the Southern Alps.

Volcanoes built the Banks and Otago Peninsulas.

In 2023 geologists finished mapping the whole landmass.

Eleven of them had already agreed it meets every test for a continent.

Its crust is thin, so it floats lower on the mantle, and that is why Zealandia sank.