New evidence strengthens the theory of the Megaflood refilling the Mediterranean Sea millions of years ago

Millions of years ago, the Mediterranean Sea evaporated. It may have been refilled by the largest flood event on Earth.

An international team of researchers has revealed new evidence supporting the Megaflood Zanclean, a theoretical event that refilled the Mediterranean Sea after a salinity crisis turned the Messinian into a dry, salty landscape. As detailed on December 28 He studies Published in the magazine Earth and environment communicationsresearchers combined newly identified geological features in Sicily with geophysical data and computer models to provide the most comprehensive look at the ancient Megaflood known to date.

“The Zanclean Megaflood was an amazing natural phenomenon, with discharge rates and flow velocities that dwarf any other known floods in Earth’s history,” said Aaron Micallef of the Monterey Research Institute in California. Southampton statement. “Our research provides the most compelling evidence for this extraordinary event.”

Between 5.97 and 5.33 million years ago, the Messinian salinity crisis caused the Mediterranean Sea to cut off from the Atlantic Ocean and evaporate into a pool of salt deposits. Scientists previously theorized that over a period of 10,000 years, the Mediterranean basin was gradually refilled with water. However, 2009 Discovery of an eroded channel This stretch from the Gulf of Cadiz on Spain’s Atlantic coast to the Alboran Sea east of the Strait of Gibraltar has challenged this theory, and instead led scientists to propose a single flood event.

“This massive overflow is thought to have caused Atlantic waters to overflow across the late Messene Isthmus near the modern Strait of Gibraltar, which initially filled the western Mediterranean, and then spilled over the Sicilian sill into the Sicilian interior, filling the eastern Mediterranean,” the researchers wrote in The new study. Scientists estimate that the Megaflood lasted between two and 16 years, exiting 2.4 and 3.5 billion cubic feet (68 and 100 million cubic metres) per second, according to the study.

The team identified more than 300 continuous asymmetric ridges near the Sicilian Threshold, a now undeveloped land bridge in the western Mediterranean from the eastern Mediterranean. The hills have been eroded in debris eroded from the flanks of the hills and the surrounding area, which indicates a rapid and intense process of deposition. The stratigraphy dates between the Messinian (7.2 million to 5.3 million years ago) and Zanclean (5.3 to 3.60 million years ago) periods, quite consistent with the proposed timing of the Zanclean Megaflood, about 5.3 million years ago.

“The morphology of these hills is consistent with erosion by large-scale water flow with a northerly direction,” Paul Carling of the University of Southampton, who participated in the study, said in the statement. “They reveal the immense power of the Zanclean Megaflood and how it reshaped the landscape, leaving lasting imprints in the geological record.”

Carling and his colleagues also discovered a “W-shaped channel” in the sea floor east of the Sicilian Threshold, connecting the ridge to an underwater canyon in the eastern Mediterranean called Noto Canyon. The researchers suggest that when the mega-zinklin filled the western Mediterranean megaflood and finally spilled over the Sicilian Threshold, the canal diverted the water to the eastern parts of the sea.

The team also developed computer models to reconstruct this dynamic. Simulations indicate that the water changed directions and grew more intense over time, achieving discharges of up to 72 miles per hour (116 kilometers per hour).

“These results not only shed light on a critical moment in Earth’s geological history but also demonstrate the persistence of landforms over five million years,” Micallef added. “It opens the door for further research along the margins of the Mediterranean.”

Although the Zanclean Megaflood is still just a theory, one thing is certain – 5.3 million years ago, the Mediterranean Sea probably would not have been the ideal travel destination it is today.