The characteristics of the canyon and how it was formed
The canyon was named after Eratosthenes and occupies an area of approximately 10 km wide and 500 meters deep. More specifically, the cannon is located in the Levant Basin, near the neighboring underwater mount Eratosthenes, hence its name.
Researchers estimate that this formed between 5.6 million and 6 million years ago, at the beginning of the Messinian period, when the Messinian salinity crisis, a geological event that involved the systems of the hydrosphere, the biosphere, the lithosphere and the atmosphere.This canyon formed at the bottom of the Mediterranean Sea at the beginning of the Messinian period, before the deposition of salt, when sea level decreased and salinity increased.
It turns out that, due to the movement of tectonic plates, the connection between the Atlantic and the Mediterranean was closed, isolating the sea from the ocean. As a result, some parts of the Mediterranean have dried up for about 700,000 years, leaving behind a vast expanse of salt up to 3 km thick.
As the sea level decreased, the increasingly salty currents advanced faster than the surrounding water and gradually eroded the seabed, opening ravines several hundred meters deep along the steepest shores of the Mediterranean Sea, forming this colossal canyon.
This discovery sheds light on a decades-long debate: whether the Messinian ravines and cannons formed above or below the surface of the sea. « This new evidence strengthens the arguments that at least part of the erosion on the continental shores occurred underwater, » the researchers said. This was just before the salt accumulated on the seabed.We argue that the increase in salinity at the beginning of the crisis and a possible limited drop in sea level would have triggered gravitational currents, destabilizing the continental margin and digging the seabed wherever it was steep enough – said the authors of the investigation.
In a broader context, the results of this investigation reveal the environmental conditions of greater salinity in the deep basins of the Mediterranean Sea before the climax of the Messinian salinity crisis.
