If the ancient supercontinents formed and separated in alternating cycles over hundreds of millions of years, in the future, probably, the Pacific will expand to become the only super-ocean of the new supercontinent, suggest scientists from the University of Curtin (Australia).
The supercontinents were connected and separated through two alternate processes called “introversion” and “extroversion,” explains the study by the researchers, published in the journal Precambrian Research.
During the first of these processes, the continent begins to divide into masses of land separated by a new internal ocean, where subduction progression is activated, the oceanic crust is submerged into the hot mantle of the Earth and the internal ocean returns to the interior of the planet. The continents meet and form of new supercontinent surrounded by the same super-ocean that was there before.
As for the extroversion procedures, subduction processes occur in the super-ocean surrounding a supercontinent. Its old coastal lines collide to form its new center, while the inner ocean transforms into a new super ocean surrounding this new supercontinent.
According to the version proposed by the Australian specialists, the supercontinent Pangea (which existed 335 million years ago) and which grouped most of the planet’s landmasses, was formed when the supercontinent Rodinia (which existed 1,100 million years ago) went backwards by the tectonic forces and consumed the super-ocean that surrounded it through the process of extroversion.
For its part, Rodinia was formed through a process of introversion after the fragmentation of the previous supercontinent Nuna (also known as Columbia), which existed, approximately, between 1,800 and 1,300 million years ago.
The reunion and separation of the ancient supercontinents occurred through alternating cycles that lasted about 600 million years, says the study’s principal investigator, Zheng-Xiang Li.
If this alternate pattern holds, according to Li, the next supercontinent will be formed through the process of introversion. The internal oceans created by the separation of Pangea – the Atlantic, the Indian and the Antarctic – will be closed and the Pacific will expand to become the only super-ocean of the new supercontinent.
This video, published on the Youtube Agol channel, explains how the formation of the Earth has changed over the years:
