Scientists have reconstructed the tumultuous history of a lost continent hidden underneath Southern Europe, which has been formally named “Greater Adria” in a new study.
This ancient landmass broke free from the supercontinent Gondwana more than 200 million years ago and roamed for another 100 million years before it gradually plunged underneath the Northern Mediterranean basin.
Researchers led by Douwe van Hinsbergen, a professor of global tectonics and paleogeography at Utrecht University, have been piecing together Greater Adria’s past for a decade. The team collected rock samples from Spain to Iran, looking for the last material remnants of the continent that are accessible to scientists.
The results were published this month in the journal Gondwana Research, and include an animated summary of the lost continent’s birth, life, and death.
Unless you live in an earthquake zone, it can be easy to forget that Earth is constantly cannibalizing its own landmasses. The map of our world morphs over the eons, as continental plates shift around, bump into each other, and undergo subduction, which occurs when one plate slides underneath another.
Greater Adria was about the size of Greenland when it slammed into Europe during the mid-Cretaceous period. At that time, most of the continent was covered by a shallow sea that supported a thriving ecosystem built around tropical reefs.
As the Adriatic plate was forced down into Earth’s mantle, the realm beneath the planet’s crust, this top layer of sediment and lifeforms was sheared right off. The messy shavings helped form the backbone of mountains such as the Alps, the Apennines, and the Taurus range.
“Much of the southern European mountain ranges are derived from Greater Adria,” van Hinsbergen said in an email. He noted that the Western and Northern Alps, and the Carpathians, are exceptions.
By collecting and analyzing rocks from these alpine locations, the team was able to identify the last surface vestiges of Greater Adria, which extend from Turin to Salento in Italy. The remains of the subducted part of the continent, which was about 60 miles thick, are also still detectable with seismometers. This underworld portion of the continent currently lies about 1,000 miles below Southern Europe.
The team was able to recreate the geological changes that Greater Adria underwent by analyzing their field data with software called GPlates. The process was like virtually peeling off the modern area layer by layer, showing its evolution since the Triassic period, van Hinsbergen explained.
“Now that we have put the jigsaw of the Mediterranean back together, we can restore other geological features, like volcanoes and ore deposits, back into their configuration in which they formed,” he told VICE.
“From that, we can learn about the fundamental drivers of such features, and also aid new ore exploration strategies, correlating across political boundaries and modern seas.”