Geologists from France and Australia studied the structure of the rocks of the French Kergolin archipelago in the southern regions of the Indian Ocean, and it became clear to them that there was a process of "continental embryo".
Terra Nova believes that the continental crust originates at the boundaries of continents and oceans, in areas called subduction sites, where the sheets of oceanic sheath dive into the Earth's mantle. After melting and mixing with the basic materials of the continental plates, granite magma is formed, which at its height forms the upper "granite" layer of the continents.
From a geological point of view, this outermost layer distinguishes the continents from the oceans: the relatively thin oceanic crust consists mainly of basaltic rocks formed as a result of the melt of mantle materials, while the continental crust is thicker and has a granite structure.
The results of the study, conducted by scientists in the volcanic archipelago of Kergolin located in the Indian Ocean close to Antarctica, show that granite magma, that is, the continental crust, can form not only in subduction areas, but also in the middle of the ocean. Researchers assume that it is in this way that new continents arise.
Since these islands are volcanic, they are basaltic rocks. But besides the traditional basalt rocks of the ocean, the researchers discovered the presence of acidic rocks - the traditional cyanite rocks. Therefore, researchers believe that the crust in the Kirgolin region is abnormally thick, as well as in continents.
It became clear to the researchers from the study of the composition of the discovered cyanite rocks, that they originated in the same way they originated in the continents in the form of layers, each of which was gradually raising the layers of the surrounding rocks. Radioactive carbon analysis showed that it was formed approximately 3.7 million years ago 11.6 - 7.9 million years ago.
Researchers have formulated their hypothesis in the following way: the presence of cyanite rocks in the islands of the Kergolin archipelago is actually a "continental embryo" that will become a whole continent after millions of years.