[即时新闻]170219-Zealandia – The eighth continent?
We used to believe there were nine planets, but now there are eight (Pluto is not a planet). Now we may have to change how many continents there are. We are taught there are seven - Asia, Africa, North and South America, Antarctica, Europe, and Australia. Geologists now say there is an eighth continent - Zealandia. This is a big, largely underwater landmass in the Pacific Ocean. Six per cent of it is above water and is New Zealand and New Caledonia. The rest is under the ocean. It is five million square kilometres, which scientists say is big enough to be a continent.
Geologists explained why Zealandia is a continent in a research paper in the Geological Society of America's Journal. They argue that the land does not have to be above water to be a continent. They said Zealandia is a continent because of four points: It is a lot higher than the area around it, it has a special geology, it is easy to see its shape, and it is thicker than the ocean floor. A geologist said it would be easy to understand that Zealandia is a continent, "if you could pull the plug on the world's oceans" and let the water out. It may take time for scientists to agree there are eight continents.
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