An ancient continent: Scientists recreated an ancient geological process, which 100 million years ago led to the fact that the whole continent of Big Adria plunged under the European part of Eurasia. This was reported on September 6 by Smardart.
Nowadays, only limestone and other rocks found in the mountain ranges of southern Europe, which were scraped off the surface of the continent when it sank under Europe, remained from Big Adria.
About 240 million years ago, a missing continent the size of Greenland broke away from the southern supercontinent of Gondwana, from which modern Africa, South America, Australia, Antarctica, India, and the Arabian Peninsula originated. Between 100 and 120 million years ago, turning counterclockwise, Adria collided with Europe, split into pieces and fell under this continent. A new study was made possible by the advent of sophisticated software.
“The Mediterranean region is just a geological mess. Everything is curved, broken and folded,” said study author Dove van Hinsbergen, a geologist at Utrecht University in the Netherlands.
Another study of seismic waves to create computed tomographic images of structures deep inside the Earth made it possible to create an “atlas of the underworld” – a cemetery of sections of the earth’s crust that drowned in the mantle of our planet. This study showed that parts of Big Adria are now at a depth of 1,500 kilometers.
Recall, earlier, scientists proved that the islands of New Zealand are the surface part of the continent, comparable in size to Australia and currently hidden under water.
An ancient continent
Duv Van Hinsbergen (Douwe Van Hinsbergen) and his colleagues note that the history of Greater Adria was colorful and not too long. The continent formed, breaking away from Gondwana about 240 million years ago (the supercontinent of Gondwana once united the territories of modern Africa, South America, Antarctica, Australia, the Arabian Peninsula and India). At first, Adria slowly, several centimeters a year, moved north, turning counterclockwise.
As a result, 140 million years ago, it turned into a vast – approximately from the island of Greenland – territory, mostly covered by shallow seas, which actively accumulated bottom sediments. And somewhere between 120 and 100 million years ago, the continent converged with the northern part of Europe – with the edge of the former supercontinent of Laurasia. Big Adria split and for the most part plunged beneath it, so that only a few fragments remained shallow beneath the surface. Today, the remains of Adria can be preserved throughout southern Europe and the Middle East, from Spain, through the entire Mediterranean and to Iran.
The authors note that coordination and implementation of work in dozens of different modern countries required special efforts. A thorough collection and fixation of samples took them a total of more than ten years. However, by carefully monitoring the orientation of magnetic minerals, geologists were able to reconstruct the movement of Big Adria not only in time but also in space.