Zealandia used to be one of the world's continents before it broke away from Australia 60 to 85 million years ago. It was also once attached to Antarctica, but detached from the frozen land mass a few million years earlier.
Roughly 93 percent of the continent is submerged under water, however the remaining seven percent is made up by New Zealand and New Caledonia. But for the first time, a group of 32 scientists from 12 countries are drilling into the sunken continent to get answers on its history.
Project director Jamie Allan said: "This expedition offered insights into Earth's history, ranging from mountain-building in New Zealand to the shifting movements of Earth's tectonic plates to changes in ocean circulation and global climate."
Credit: Wikimedia Commons
They embarked on a nine-week voyage (which is roughly the same time it would take to travel by boat from the UK to Sydney twice) and collected 2,500 metres of rock samples and sediment. The team are hoping this will shed light on how the geology, volcanism and climate led to Zealandia being buried by the sea.
Expedition co-chief scientist Gerald Dickens from Rice University, Houston, said: "More than 8,000 specimens were studied, and several hundred fossil species were identified.
"The discovery of microscopic shells of organisms that lived in warm shallow seas, and of spores and pollen from land plants, reveal that the geography and climate of Zealandia were dramatically different in the past."
The group says these finds should also help to explain how and why some plants and animals exist in both New Zealand and New Caledonia.
Credit: NOAA
There was a push earlier this year for Zealandia to be recognised as Earth's eighth continent. A paper published in the Geological Society of America's Journal argued that the land mass (regardless of whether it was submerged) is two-thirds the size of Australia.
The authors of the research said Zealandia fulfilled a certain set of criteria which could guarantee its status as a continent. That includes elevation above the ocean floor, a broad range of geology, a well-defined area and a crust thicker than the regular ocean floor.
Technically, they aren't wrong, considering the Glossary of Geology defines a continent as: "One of the Earth's major land masses, including both dry land and continental shelves." Labelling it the eighth continent would result in virtually every textbook on the subject needing to be rewritten. But we have seen this sort of thing before - remember when Pluto was brutally erased from the list of planets in our solar system?
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Sources: Eureka Alert, GeoSociety
Topics: New Zealand, Research, Australia