We all have known since childhood that there are seven continents in the world. But have you ever thought furthermore, about the existence of Earth's eight continent ? Maybe not. Well, then you might be startled by knowing that a recent research has discovered the existence of the eight continent of the world, named Zealandia (also known as Te Riu-a-Māui), beneath New Zealand, being submerged into the Pacific Ocean.

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If we go back to the 240 million years old earth, then you might find the map of the world quite different. All the present landmasses (e.g. continents, countries, islands) were set in together as a giant super-continent named as Pangea. It chronologically split into today's continents, of which the northern part known as Laurasia land, and the southern part known as the Gondwana land. These eventually developed today's modern continents, i.e., Asia, Europe, North America, South America, Africa, Oceania, Antarctica.

Maximum portion of Zealandia is under water of southern Pacific Ocean. Thus it seemed to be quite challenging to map out the extent of this lost eighth continent of Earth, until a recently conducted study by the scientists from GNS Science in New Zealand. They have succeeded to map the shape and size of Zealandia with unprecedented detail.

Nick Mortimer, the lead researcher, mentioned in the interactive website of GNS Science,
We have made these maps to provide a complete, accurate and up to date picture of the geology of New Zealand as well as the southwest Pacific area- better than we have had before.

Scientists have prepared the tectonic map and bathymetric map of Zealandia, which provide us interesting informations about size, shape, tectonic status, ocean floor depth, and as well as an idea about the formation of Earth's eighth continent Zealandia before it get submerged deep into the Pacific Ocean.


85 million years old origin of Zealandia

Though concept of Zealandia had developed recently, but the history of Zealandia is beyond thinking– its approximately 85 million years old.

American geophysicist Bruce Peter Luyendyk coined the name ‘Zealandia’ in 1995. But that time he did not refer it as a continent, rather he used it to describe the whole composition of New Zealand and adjacent waterlogged landmasses, that split from Pangea millions of years ago.

As mentioned previously that Pangea split into Laurasia land and Gondwana land, geologic processes leads to the development of the continents of northern and southern hemisphere, and accordingly forced Zealandia to get submerged into the ocean, almost 30 to 50 million years afterward, since it dispersed from Pangea.


Findings of the research on Zealandia

The research reveals that Zealandia covers nearly 5 million square kilometres (or 2 million square miles) area, which is approximately half of the total landmass of Australia.

They mentioned that only 6% of Zealandia is raised above the ocean surface which includes whole New Zealand, New Caledonia, and some other minor islands of south-western Pacific region.

The hard toil of scientists for better understanding about this ‘lost’ eighth continent of Earth, have resulted to the outcome of tectonic map and bathymetric map of Zealandia.


Tectonic map of Zealandia


Tectonic_map_of_Zealandia
Tectonic Map of Zealandia | Image Courtesy : GNS Science

The tectonic map of Zealandia, prepared by the scientists, reveals the tectonic location and status of the tectonic plates around Zealandia. It includes the mapping of the subduction zones of the plate boundaries of that area.

This tectonic map also includes a colourful description about tectonic history of the new continent. The map provides a clear idea of the crust structure. Such as, the main landmass of Zealandia or the continental crust is shown in orange, red, yellow and brown colour. These collectively depicts the old Gondwana landmass. Whereas, in other side, the comparatively young oceanic crust is shown in variation of blue colour. The underwater volcanoes are also demarcated with red triangles.


Bathymetric map of Zealandia


Bathymetric_Map_of_Zealandia
Bathymetric Map of Zealandia | Image Courtesy : GNS Science

The bathymetric map of Zealandia implies the ridges, territorial extent, coastline of the continent. The map also includes naming of various geologic features which are submerged thousands of feet beneath the Pacific Ocean.

It needs to be mentioned in this context, this bathymetric map is a part of ‘Seabed 2030’ project, which is a global exertion to map the whole ocean floor of the Earth by 2030, and about 20% of this project is completed till date.


A landmass must have to fulfill some criteria to introduce itself as a continent. Such as,
  • It must cover an area of minimum 1 million square kilometres with clearly defined limits.
  • It must be surrounded by ocean(s).
  • Its crust will be thicker and older than ocean crust, and the entire landmass have to be raised above the surrounding ocean crust, etc.
Hence, it is seen that Zealandia meets all the criteria, for which scientists claim Zealandia as the 8th continent of Earth alongside the other 7 continents.


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