Zealandia (continent)
Coordinates: 40°S 170°E / 40°S 170°E
Zealandia (pronunciation: /ziːˈlændiə/), also known as the New Zealand continent or Tasmantis, is a nearly submerged continental fragment that sank after breaking away from Australia 60–85 Ma (million years) ago, having separated from Antarctica between 85 and 130 Ma ago.
The land mass may have been completely submerged about 23 Ma ago, and most of it (93%) remains submerged beneath the Pacific Ocean. How strongly Bollons Seamount (south of the Chatham Islands) remains connected to Zealandia is unknown. With a total area of approximately 4,920,000 km2 it is the world's largest current microcontinent, more than twice the size of the next-largest microcontinent and more than half the size of the Australian continent.
As such, and due to other geological considerations, such as crustal thickness and density, it is arguably a continent in its own right. This was the argument which made news in 2017, when geologists from New Zealand, New Caledonia and Australia concluded that Zealandia fulfills all the necessary requirements to be considered a continent, rather than a microcontinent or continental fragment.
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