A large pocket of water is still buried deep below a mountain range in Sicily
A large pocket of fresh water that was sucked down into Earth's crust 6 million years ago is still buried deep below a mountain range in Sicily, new research has found.
The fresh water likely became trapped underground during the Messinian salinity crisis, when the Mediterranean Sea dried up following a global cooling event that locked ocean water up in ice sheets and glaciers. This event likely exposed the seabed to rainwater that then trickled down into Earth's crust, according to a study published Nov. 22 in the journal Communications Earth & Environment.
The rainwater accumulated and formed an aquifer that stretched between 2,300 to 8,200 feet (700 to 2,500 meters) deep beneath the Hyblean Mountains in southern Sicily, Italy, and has not budged since.
In the new study, researchers investigated deep groundwater reserves in and around the Gela formation, which is a known oil reservoir and hosts several deep wells, harnessing publicly available data from these wells. They constructed 3D models of the aquifer and estimated it holds 4.2 cubic miles (17.5 cubic kilometers) of water — more than twice as much as is held in Scotland's Loch Ness.
The researchers then used the 3D models to turn back the clock and reconstruct the past geology of the study area, which stretched across the Hyblaean Plateau and the Malta Plateau in the central Mediterranean. During the Messinian (7.2 million to 5.3 million years ago), fresh water infiltrated Earth's crust several thousand feet below current sea levels as a result of the salinity crisis, their results showed. The crisis saw sea levels drop about 7,870 feet (2,400 m) below current levels in parts of the Mediterranean.
