Current Affairs Brain Booster for UPSC & State PCS Examination (Topic: Zealandia)

Brain Booster for UPSC & State PCS Examination

Current Affairs Brain Booster for UPSC & State PCS Examination

Zealandia

Earth's mysterious eighth continent doesn't appear on most conventional maps; that's because almost 95% of its land mass is submerged thousands of feet beneath the Pacific Ocean.
Researchers from GNS Science in New Zealand announced that they'd mapped the shape and size of the continent in unprecedented detail. They put their maps on an interactive website so that users could virtually explore the continent.
GNS Science is a New Zealand Crown Research Institute. It focuses on geology, geophysics, and nuclear science.

Scientists confirmed the existence of an eighth continent, called Zealandia, under New Zealand and the surrounding ocean in 2017. ( But they hadn't been able to map its full breadth until now.
The submerged continent of Zealandia broke away from the supercontinent Gondwanaland about 80 million years ago.
For the past 23 million years the massive continent has been nearly completely submerged. In total, the continent is 1.9 million square miles and is about half the size of Australia.
About 94 percent of Zealandia is underwater with the only above water landmasses making up a few Pacific islands including New Zealand.
Nick Mortimer and his team, who led the work, mapped the bathymetry surrounding Zealandia — the shape and depth of the ocean floor — as well as its tectonic profile showing where Zealandia falls across tectonic-plate boundaries.

Bathymetry is the measurement of the depth of water in oceans, rivers, or lakes.
Bathymetric maps look a lot like topographic maps, which use lines to show the shape and elevation of land features.
On topographic maps, the lines connect points of equal elevation. On bathymetric maps, they connect points of equal depth.
Today, echo sounders are used to make bathymetric measurements. An echo sounder sends out a sound pulse from a ship’s hull, or bottom, to the ocean floor. The sound wave bounces back to the ship. The time it takes for the pulse to leave and return to the ship determines the topography of the seafloor. The longer it takes, the deeper the water.
Multibeam echo sounders can also provide information about the physical characteristics of a seafloor feature.

Zealandia once made up approximately 5% of the area of Gondwana. It contains the principal geological record of the Mesozoic convergent margin of southeast and, until the Late Cretaceous, lay Pacificward of half of West Antarctica and all of eastern Australia.
Thus, depictions of the Paleozoic-Mesozoic geology of Gondwana, eastern Australia, and West Antarctica are both incomplete and misleading if they omit Zealandia.
The importance of Zealandia is not so much that there is now a case for a formerly little-known continent, but that, by virtue of its being thinned and submerged, but not shredded into microcontinents, it is a new and useful continental end member.
Zealandia illustrates that the large and the obvious in natural science can be overlooked.
Currently used conventions and definitions of continental crust, continents, and microcontinents require no modification to accommodate Zealandia.