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The formation of a new embryonic continent began in the southern Indian Ocean. This conclusion was made by French and Australian geologists following the study of the rocks’ composition.

It is believed that the continental crust grows on the borders of continents and oceans in the so-called subduction areas, where oceanic lithospheric plates sink into the mantle beneath the continent. When they are remelted and mixed with the base material of continental plates, granite magma is formed, which creates the upper granite layer of the continents, RIA Novosti reports with reference to the Terra Nova Magazine.

From a geological point of view, this outer layer distinguishes the continents from the oceans: the relatively thin oceanic crust consists mainly of basalts formed in the process of the melting of mantle material. Meanwhile, the continental crust is thicker and has a granite composition.

The results of a study conducted by scientists on the Kerguelen Islands in the Indian Ocean near Antarctica show that granite magma, and accordingly the continental crust, can form not only in subduction areas, but also in the center of the oceans. The authors suggest that this is how new continents emerge.

The islands of the archipelago are in fact the peaks of volcanoes towering above the water, breaking through the oceanic crust of the Kerguelen Plateau. The basalts that erupted out of them had shaped the islands. But along with the traditional for the oceans basalts, there is one intrusion of more acidic rocks of the granite family, found only on the continents. Due to this intrusion, the crust in the Kerguelen region is thick, as on the mainland.

Based on the study results, scientists formulated the hypothesis that the syenitic massif of the Kerguelen Island is the embryo of the continent, which will be a completely shaped continent in millions of years.

It was previously reported that an underwater volcanic eruption flooded one of the islands of the Tongan archipelago, while creating another three times larger island. According to Taaniela Kula, an employee of the Geological Survey of the Kingdom of Tonga, a new island is about 400 meters long and 100 meters wide. It is located 120 meters west of its flooded precursor.

The emergence of a new island was promoted by an 18-day underwater eruption, which occurred in October in an area prone to earthquakes and volcanic activity.

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