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There’s a Lost Continent 1,000 Miles Under Europe

ExtremeTech

Lost continents have always fascinated people. From fictional lands like Mu and Atlantis, to the actual “lost” lands and microcontinents like Zealandia (now almost entirely beneath the waves) and Doggerland (sunk by sea level rise at the end of the last ice age), humans have researched and theorized about how these lands came to be lost to us and the animals and civilizations that may have lived upon them. But continents don’t just vanish beneath the ocean — they also disappear into the Earth itself.

Surface crust is created by mid-oceanic rifting, as tectonic plates separate, and subducted in zones where it slams into other plates, forcing one plate under the other. More than 200 million years ago, a chunk of crust nicknamed Greater Adria broke free from the supercontinent Gondwana. A team of researchers studying mountain ranges from Spain to Iran for the past decade has discovered that a strip of this crust running from Turin to the heel of Italy’s “boot” still exists today, even though the rest of Greenland-sized island has since vanished. As the island subducted, pieces of it scraped off against mountain ranges that are now part of the Apennines and the Alps. Remnants also exist in the Balkans, Greece, and Turkey.

“Most mountain chains that we investigated originated from a single continent that separated from North Africa more than 200 million years ago,” says principal researcher Douwe van Hinsbergen, Professor of Global Tectonics and Paleogeography at Utrecht University. “The only remaining part of this continent is a strip that runs from Turin via the Adriatic Sea to the heel of the boot that forms Italy.”

Geologists refer to that area as “Adria.” Van Hinsbergen has therefore called the lost continent “Greater Adria.”

The Mediterranean is an extremely complex geological structure, which is scientist-speak for “There’s an awful lot of smashed-together geology all over the place.” The video below shows how the Mediterranean formed over millions of years.

The reason the southern mountain ranges of Europe are derived from Greater Adria when virtually all of the rest of the continental crust is now buried beneath the Earth is that these sections of crust literally scraped off as the plate was crushed. There are exceptions; the Western and Northern Alps are not derived from Greater Adria, and neither are the Carpathians. The rest of Greater Adria now lies more than a thousand miles below the surface of the planet, in Southern Europe. Scientists have been mapping sunken sections of continental crust for years now, and have detected remnants of crust that were once on top of the Earth’s surface in previous expeditions. There are buried remnants of our own past now locked away far inside the mantle.

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September 18th 2019, 8:12 am
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