Geology books will likely have to add a new continent shortly: Zealand. With an area of 4,9 million square kilometers, is almost completely submerged in the waters of the Pacific Ocean, to the point that its only visible parts are New Zealand and New Caledonia.
The existence of Zealandia was recently confirmed by scientists from the New Zealand center GNS Science, who have been investigating the possible existence of the continent for 20 years. Through data collected by underwater sensors, they have managed to discover an area that brings together the conditions necessary to be classified as a continent.
You might think that the fact that it has almost the 95% of its territory is under water This would be enough to disqualify it from being classified as a continent. However, because it has a well-defined area, a crust thicker than the ocean floor, and is higher than the surrounding area, it has been possible to elevate it to the category of continent, according to the study published in the journal of the Geological Society of America (GSA).
The geologist and leader of the research, Nick Mortimer, expressed that this discovery will serve not only to add it to the science books, but also to be able to explore the cohesion and disintegration of the continental crustIt is the thinnest and smallest continent ever found, which, despite being submerged, has not fragmented.
Mortimer and his team hope that Zealandia will be recognized by the scientific community and appear on the world map. Despite being almost entirely underwater, satellite data and research surveys indicate that it is a royal continentHowever, they will have to wait for other researchers to mention it in their studies.
History of Zealandia
The discovery of Zealandia has its roots in the past, where geologists from classical Greece such as Aristotle, Eratosthenes and later the cartographer Ptolemy They mentioned an imaginary continent which they called Terra Australis IgnotaIn search of this land mass, the Dutch explorer Abel Tasman In 1642 he came across the islands we know today as New Zealand, although those lands seemed too small to be what he was looking for.
Since the discovery of Tasman, there have been 375 years until a team of scientists confirmed that the continent, known as Zealandia, actually existed, although most of it is underwater. It is estimated that 94% of its surface is submerged.
A new study published in tectonics by scientists at GNS Science has produced a definitive map of Zealandia. This continent stretches across 5 million square kilometers, and it was not until now that its existence could be established full surfaceThe history of Zealandia is linked to that of Gondwana, an ancient supercontinent that fragmented hundreds of millions of years ago, giving rise to the land masses we know today. The study of the continents is essential to understand this context.
Geological features of Zealandia
Zealandia broke away from Gondwana approximately 80 million yearsUnlike its neighboring continents, such as Antarctica or Australia, which remain largely above sea level, most of Zealandia's territory is submerged. Only the islands of New Zealand, New Caledonia, and small territories such as the island of Lord Howe and the pyramid of ball emerge above the waters.
Mortimer's team's research has made it possible to define the two thirds were missing of Zealandia and refine existing maps. “Reconnaissance geological mapping of the entire 5 million km2 continent of Zealandia is now complete,” Mortimer said.
To understand Zealandia's geology, the team analyzed rock and sediment samples from the ocean floor, mostly from drill holes and also from the islands' shorelines. Among the materials analyzed were basalts, sandstones y sandstone pebblesThe sandstones were found to be of Upper Cretaceous age (about 95 million years old) and contained granite and volcanic pebbles from the Early Cretaceous. The basalts were dated to the Eocene, about 40 million yearsThis analysis provides data for understanding the volcanic activity in the region.
The results, along with data from regional magnetic anomalies and other studies helped scientists map the underwater geology of North Zealandia. The first European sighting of the area was in 1642 by Abel Tasman. Since then, other explorers and scientists have sailed the waters around Zealandia in search of the lost continent, unaware that they were floating above it.
The implications of the discovery of Zealandia
The continental crust is usually about 1000 feet deep. 40 km and is significantly thicker than oceanic crust, which typically has about 10 km. In comparison, Zealandia has about 20 km deep because its platform extended significantly as it separated from Gondwana. Although it eventually sank, it did not do so to the level of the normal oceanic crust.
Based on the depth of its crust and the type of rocks it is made of, scientists say Zealandia meets all the criteria to be considered a continent. This recognition has important implications, not only in geological terms, but also political and economic ones.
La United Nations Convention on the Law of the Sea allows countries to extend their legal territories beyond their Exclusive Economic Zone, which reaches the 370 km from its shores, to claim its extended continental shelf, which includes mineral and oil resources. Thus, by demonstrating that Zealandia is part of a larger continent, New Zealand could see its territory increase six times.
This has led to an increase in the funds available for the marine exploration of the region, making the study of . relevant.
Over the past few years, numerous studies and research have been carried out on Zealandia. One of the most significant findings indicates that the crust of this continent is considerably thinner than that of other landmasses, but it meets several criteria that position it as a legitimate continent. Recent studies have suggested that Zealandia has a rich geological history that may provide valuable information about the tectonic processes and the evolution of the Earth.
In 2021, a study suggested that Zealandia has more billion years, which is roughly double what was previously believed in research. This further highlights Zealandia's importance in geology, as it is possibly one of the oldest formations on Earth.
Zealandia's future in science and exploration
Zealandia has been divided into two main regions: North Zealandia (or Western Province) and South Zealandia (or Eastern Province). These two formations are separated by the Alpine Fault and the Kermadec Trench, along with the Hikurangi Plateau. This separation allows us to study how Zealandia was formed and how it relates to nearby continental landmasses in geological history.
As sea levels have fluctuated at different periods, it has been suggested that the continent played an important role in the origin of the Pacific Volcanic Ring of FireThis discovery will not only change the way we think about the geography of the Pacific Ocean, but will also offer new opportunities for scientific research.
The scientific community continues to study Zealandia to learn more about plate tectonics, volcanic activity, and the evolution of the region's flora and fauna. Recent studies have revealed that volcanoes have erupted on Zealandia several times throughout its history, but currently, volcanic activity is low, except in certain specific regions.
For geologists around the world, Zealandia represents a window into bygone eras and an opportunity to deepen our understanding of how tectonic plates influence the formation of continents and their impact on the planet. processes that shape the EarthAlong these lines, a growing interest in marine exploration could increase the amount of data available on this submerged continent.
