To the naked eye, Earth’s continents appear static. However, due to certain geological processes, these gigantic masses have moved in the last hundreds of millions of years. Now, according to recent studies, a supercontinent called Amasia is forming, in which South America will eventually join Antarctica and Australia.
Given the movement of tectonic plates below the Earth’s surface, as well as other geological evidence, scientists know that between 340 and 180 million years ago, all the continents were together and made up the supercontinent Pangea. In recent decades, it has been found, for example, that the American continent is moving away from Europe and Africa —at the same time that it is getting closer to Asia— at a rate of four centimeters per year.
What is happening now?
One of the most recent investigations into this phenomenon was carried out by scientists from Curtin University in Australia and Peking University in China. “We designed a spherical Earth-like system using supercomputers and mimicking Earth’s internal structures, properties and processes such as plate tectonics and mantle convection,” Zheng Xiang Li, co-author of the study, told the BBC. “We then ran a series of model simulations to see what factors might control the way a supercontinent forms”, he added.
The results revealed that the crust under the oceans (7 to 8 km thick) has become thinner due to the internal cooling of the planet, which is why it ends up giving way to the movement of the plates under the continents. “Our result shows that, with the secular cooling of the Earth’s mantle, the overall force of the oceans becomes weaker. The Pacific Ocean will shrink enough to become a smaller ocean than the expanding Atlantic and Indian Oceans”, said Chuan Huang, lead author of the study.
The new supercontinent: when and how will it be formed?
The study, published in the National Science Review, indicates that the Pacific Ocean, which is currently shrinking a few centimeters per year, will end up closing in less than 300 million years, consolidating the union of the continents. First, Australia will collide with Asia; then, it will join South America (already separated from the rest of the continent) and Antarctica; finally, it will do so with North America and Central America.
The name of Amasia is due to the fact that the North American territory will end up united with the Asian one, but, in reality, this supercontinent could stand out for any of the other unions. The authors suggest that the formation of Amasia will lead to lowering sea levels, reduced biodiversity and a huge portion of arid land in the interior of the supercontinent, such as the central part of the current continents: the Sahara, Arizona , Mongolia, etc.
