‘Zealandia’ – Scientists discover new continent


Scientists Discover New Continent – Zealandia


New Continent – Zealandia

  • Scientists, have recently found out that there is a new continent on Earth named ‘Zealandia’.
  • Scientists claim the ‘continent’ had been hidden and virtually invisible to the human eye for a millenia, until now.
  • The research carried out by some 11 scientists makes the case for the eighth continent by establishing that New Zealand and New Caledonia are not just an island chain.
  • As per these scientists observation, New Zealand and New Caledonia are part of 4.9 million square kilometer earth crust that is different from Australia.
  • Till now, it has known that Earth has only seven continents, namely Asia, Africa, Europe, South America, North America, Antarctica and Australia.

New continent

New Continent – Historical background

  • The concept of Zealandia is not new. In fact, Luyendyk coined the word in 1995. But Luyendyk says it was never intended to describe a new continent. Rather, the name was used to describe New Zealand, New Caledonia, and a collection of submerged pieces and slices of crust that broke off a region of Gondwana, a 200 million-year-old supercontinent.
  • Researchers behind the new study took Luyendyk’s idea a huge step further, re-examining known evidence under four criteria that geologists use to deem a slab of rock a continent:
    1. Land that pokes up relatively high from the ocean floor
    2. A diversity of three types of rocks: igneous, metamorphic, and sedimentary rocks
    3. A thicker, less-dense section of crust compared to surrounding ocean floor
    4. “Well-defined limits around a large enough area to be considered a continent rather than a microcontinent or continental fragment”
  • Over the past few decades, geologists had already determined that New Zealand and New Caledonia showing the characters of above mentioned points 1, 2, and 3.
  • These are large islands that poke up from the sea floor, are geologically diverse, and are made of thicker, less-dense crust.
  • This eventually led to Luyendyk’s coining of Zealandia, and the description of the region as ‘continental’, since it was considered a collection of microcontinents, or bits and pieces of former continents.
  • At a glance, this new continent – Zealandia seemed broken-up. But the new study used recent and detailed satellite-based elevation and gravity maps of the ancient seafloor to show that Zealandia is indeed part of one unified region.

New Continent – Geological features

  • The study’s authors point out that while India is big enough to be a continent, and probably used to be, it’s now part of Eurasia because it collided and stuck to that continent millions of years ago.
  • Zealandia, meanwhile, has not yet smashed into Australia; a piece of seafloor called the Cato Trough still separates the two continents by 25 kilometres (15.5 miles).
  • In case for Zealandia the plate is divided into northern and southern segments by two tectonic plates: the Australian Plate and the Pacific Plate.
  • This split makes the region seem more like a bunch of continental fragments than a single slab.
  • But the scientists point out that Arabia, India, and parts of Central America have similar divisions, yet are still considered parts of larger continents.
  • The researchers also wrote, rock samples suggest Zealandia is made of the same continental crust that used to be part of Gondwana, and that it migrated in ways similar to the continents Antarctica and Australia.