- The eighth continent, called Sealand, Hidden under New Zealand and the surrounding Pacific Ocean.
- Since 94% of Zealandia is submerged, it is possible to distinguish the age and Map it It’s hard.
- New research shows that Sealandia is 1 billion years old, about twice as long as geologists think.
- For more stories, please visit www.BusinessInsider.co.za.
Approximately 3,500 feet below the South Pacific is a piece of land measuring 2 million square miles (5.2 million square kilometers)-about half the size of Australia.
But scientists couldn’t reach an agreement on whether this submerged piece of land. Sealandia, Is it mainland?Geologist team Declared as one 2017, but not all researchers believe it.
“It’s not like a mountain, a country, or a planet. There is no formal agency to approve a continent,” Nick Mortimer, a New Zealand GNS Science geologist who led the 2017 team, told Insider.
Although the definition of a continent is controversial, Mortimer’s team suggested that the continent should have a clear boundary, an area greater than 386,000 square miles (1 million square kilometers), higher than the surrounding oceanic crust, and the continental crust is thicker than that of the oceanic crust.
Sealandia meets all these regulations.
Mortimer said: “If you want to drain the ocean, Sealandia will become a well-defined plateau above the ocean floor.”
He considered it to be “the thinnest, deepest, and smallest continent.”
However, the problem is that until recently, the oldest crust and rocks collected from Sealand were only 500 million years old, while all other continents contained crusts of 1 billion years or more. But a recent study The discovery that part of the submerged continent is twice as old as geologists previously thought may support Mortimer’s argument.
“This new study outlines the last continental frame,” said New Zealand geologist Rose Turnbull, co-author of the study. In the press release“There is no doubt that we live on one continent.”
How to date a continent
Aaron Choi/Shutterstock
Sealandia is a term coined by the geophysicist Bruce Luyendyk in 1995. It consists of New Zealand and a series of submerged crust blocks that fractured from the ancient Gondwana continent. About 85 million years ago.
Approximately 94% is underwater-Sealandia sank under the waves about 30-50 million years after leaving Gondwana. Therefore, this is a challenging land to study.
The geologists behind the recent research studied 169 Zeelandia granites found under the South Island and Stewart Islands in New Zealand. Granite is formed when magma crystallizes deep in the earth’s crust.
By extracting microscopic crystals from granite, the team was able to determine the age of the crystals themselves and the crust that formed them. The results show that the crust was once part of another supercontinent called Rodinia, which was formed 1.3 to 900 million years ago.
In other words, the geological history of Sealandia predates 500 million years ago.
Map Sealandia in unprecedented detail
Global Navigation Satellite System Science
part Turnbull’s mission Was to create a 4D map of the west coast of Zelandia-to visualize how the border looks in three dimensions and how it changes over time.
Last year, Mortimer helped map the shape and depth of the sea floor around Zealand-this is the so-called bathymetry map.
The map is part of a global initiative to survey the entire ocean floor of the earth by 2030, and it also reveals the size and coastline of Zealand in unprecedented detail. In addition, Mortimer’s team also drew a structural map showing the location of the continental and oceanic crust that make up the submerged land.
Mortimer said that these new, detailed maps, coupled with the discovery that parts of the Sealand continent are older than geologists realized, provide further evidence that it should be considered the eighth continent.
He said: “We hope that Sealandia will eventually appear on the world map, taught in schools, and become a familiar name like Antarctica.”
