Lost Continent of ‘Greater Adria’ Revealed

September 13, 2019

A highly detailed re-creation of the past 240 million years showcases the tangled tale of an ancient continent dubbed Greater Adria.

Take a hike along the mountain belts scattered around the Adriatic Sea, and you may find yourself clambering across the crumpled leftovers of a long-lost continent.

This rocky jumble represents the ruins of a Greenland-size piece of continental crust that was demolished millions of years ago, scientists report this month in the journal Gondwana Research. The saga of the continent’s demise is part of a new report that re-creates the last 240 million years of the Mediterranean’s tectonic history in unprecedented detail.

The model shows how this continent first separated from what is now Spain, southern France, and northern Africa, forming a separate landmass the team has formally dubbed Greater Adria. But as the planet’s rocky plates continued to inexorably jostle about, this continent tumbled down into several subduction zones, Earth’s destructive geological maws. (Find out what may happen when Earth’s tectonic plates grind to a halt.)

As it dove into the hellish depths of the mantle, the top layer of the continent was scraped away, as if a titan were peeling a colossal apple. This wreckage was dumped onto the overlying plates, ready to form future mountains along the spine of Italy, as well as in Turkey, Greece, the Alps, and the Balkans.

Several slivers of the continent dodged both a gnarly shave and slow obliteration through subduction. These unsullied relics of Greater Adria can be found today in the heel of Italy’s boot, scattered from Venice to Turin, and in Croatia’s Istria region—which means you can take a vacation on the splinters of a lost continent.

Reconstructing this slice of our geologic past is key to understanding the present, says study leader Douwe van Hinsbergen, an expert in tectonics and ancient geography at Utrecht University.

“Everything that you see around you that wasn’t wood or cloth was found by a geologist in a mountain,” he says. Ores, metals, and minerals that are now vital to civilization can be found within these peaks, and over time, interlinked caches of them have been fragmented by plate tectonics pandemonium.

Models like the one in the new study can allow us to rewind the clock and watch this dissection take place. If a deposit of copper, for example, is found in one country, such reconstructions allow us to work out where its once-connected shards may have ended up, effectively creating the treasure maps of the modern era.

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