Greater Adria, a lost continent hiding in plain sight
Most of it was eaten by Earth's mantle, but scraped-off bits survive in the Alps and other mountain ranges.
18 October, 2019
Image: Utrecht University
- Following a 10-year survey, geologists discover a lost continent in the Mediterranean.
- 'Greater Adria' existed for 100 million years, and was probably "great for scuba diving".
- Most of it has been swallowed up by Earth's mantle, but bits of it survive.
Complex geology
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjAxMjUxMC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzMDE4OTI2MH0.IenexvWxtpY_jWTI8pipCmvDmBPliVqR7Hgdf8fnpHU/img.jpg?width=980" id="b8d85" class="rm-shortcode" data-rm-shortcode-id="34380b4a09917c1b51d9e41bcefb057d" data-rm-shortcode-name="rebelmouse-image" alt="Topographic map of the Mediterranean Sea basin, once home to the continent of Greater Adria." />Topographic map of the Mediterranean Sea basin, once home to the continent of Greater Adria.
Image: NASA / public domain
<p>Move over, Atlantis. Not all lost continents are myths; here's one whose existence has just been verified by science. Greater Adria broke off from North Africa 240 million years ago. About 120 million years later, it started sinking beneath Southern Europe. But bits of it remain, scattered across local mountain ranges.</p><p><span></span>It's the geological similarities in those mountains that had led scientists to hypothesize the presence of an ancient continent in the Mediterranean. But the region's geology is so complex that only recent advances in computing—and a 10-year survey by an international team of scientists—were able to produce a geo-historical outline of that former land mass. This is the very first map of the world's latest lost continent (1).</p><p><span></span>The 100-million-year history of Greater Adria starts nearly a quarter of a billion years ago. The world was a very different place back then. It was just recovering from the Permian-Triassic extinction, which came pretty close to wiping out all life on Earth. The planet was repopulated by the first mammals and dinosaurs. </p>Supercontinental break-up
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjAxMjUxMS9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTY0NTc1MjUzOH0.FbnnsJ0E5VT3P_iIhaFCq0bhrQ1YmOytSoPP1JPRwJY/img.png?width=980" id="69ff1" class="rm-shortcode" data-rm-shortcode-id="30f64dbadb64a83eb8c3c9fc677278a0" data-rm-shortcode-name="rebelmouse-image" alt="All together now: the supercontinent of Pangaea (335-175 million years ago)." />All together now: the supercontinent of Pangaea (335-175 million years ago).
Image: Kieff / GFDL 1.2
<p>Oblivious that biological imperative, Earth's geology was on a course of its own: fragmentation. At that time, the planet's land masses had coagulated into a single supercontinent, <a href="https://bigthink.com/news/pangea-politico-map-reveals-modern-countries-on-the-ancient-supercontinent" target="_blank" rel="noopener noreferrer">Pangaea.</a> </p><p>Around 240 million years ago, a Greenland-sized piece of continental plate broke off from what would become North Africa and started drifting north. Between 120 and 100 million years ago, the continent smashed into Southern Europe. Even though the speed of that collision was no more than 3 to 4 cm per year, it ended up shattering the 100-km thick crust. </p><p>Most of the continental plate was pushed under Southern Europe and swallowed up by Earth's mantle, a process known as subduction. Seismic waves can still detect the plate, now stuck at a depth of up to 1500 km. <br></p><p>But some of the sedimentary rocks on top were too light to sink, so they were scraped off and got crumpled up—the origin of various mountain chains across the Mediterranean region: the Apennines in Italy, parts of the Alps, and ranges in the Balkans, Greece and Turkey. </p>Death and birth
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="b6e9d18f5ebe97540b2acf42bfddcdfa"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/tf9r2SmTJ1A?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>Flowing from present to deep past, this time-lapse reconstruction of the geological history of the Mediterranean shows the death and birth (in that order) of Greater Adria in unprecedented amounts of detail.</p><p>Some bits of Greater Adria survived both the shave-off into mountainhood and death by subduction. "The only remaining part of this continent is a strip that runs from Turin via the Adriatic Sea to the heel of Italy's boot," says Douwe van Hinsbergen, Professor of Global Tectonics and Paleogeography at Utrecht University, and the study's principal researcher. That's an area geologists call 'Adria', so the team, consisting of scientists from Utrecht, Oslo and Zürich, called the lost continent 'Greater Adria'. </p><p>What was the continent like? A shallow continental shelf in a tropical sea, where sediments were slowly turned into rock, Greater Adria possibly resembled Zealandia, a largely submerged continent with bits sticking out (i.e. New Zealand and New Caledonia), or perhaps the Florida Keys, an archipelago of non-volcanic islands. Either way, dotted with islands and archipelagos above the water, and lots of coral below, it was "probably good for scuba diving," Van Hinsbergen says.<br></p><p>It took scientists this long to produce the first map of Greater Adria not just because the Mediterranean is, in the words of Van Hinsbergen, "a geological mess (…) Everything is curved, broken and stacked. Compared to this, the Himalayas represent a rather simpler system." Greater Adria perished by subduction and scraping-off. The Himalayas emerged by the collision of two continents. </p>Ore deposits
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjAxMjUxOS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1NDU3MzkxN30.LM6bVix9CeDUg5vzUre2skxcxyk0hYHQFUjLatA29R0/img.jpg?width=980" id="02403" class="rm-shortcode" data-rm-shortcode-id="7a95c1d043c006bd0853cdf3564fec5e" data-rm-shortcode-name="rebelmouse-image" alt="A reconstruction of Greater Adria, Africa and Europe about 140 million years ago. In lighter green, submerged parts of continental shelves." />A reconstruction of Greater Adria, Africa and Europe about 140 million years ago. In lighter green, submerged parts of continental shelves.
Image: Utrecht University
<p>The region also has a complex geopolitical makeup, obliging the researchers to piece together evidence from 30 different countries, from Spain to Iran, "each with its own geological survey, own maps, own ideas about evolutionary history. Research often stops at national borders."<br></p>So what has geology learned from the discovery of Greater Adria?<ul><li>First off, that its hypothesis was right: Geological similarities across the Mediterranean really did point to a lost continent, now found.</li><li>Secondly, the reconstruction of Greater Adria has also taught geologists that subduction is the basic way in which mountain belts are formed.</li><li>They've also learned a great deal about volcanism and earthquakes, and "(we) can even predict, to a certain extent, what a given area will look like in the far future," van Hinsbergen says.</li><li>Finally, and practically, these insights will help scientists and surveyors to identify and locate ore deposits and other useful materials in mountain belts. </li></ul>
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Why the south of Westeros is the north of Ireland
As Game of Thrones ends, a revealing resolution to its perplexing geography.
16 May, 2019
Image: YouTube / Doosh
- The fantasy world of Game of Thrones was inspired by real places and events.
- But the map of Westeros is a good example of the perplexing relation between fantasy and reality.
- Like Britain, it has a Wall in the North, but the map only really clicks into place if you add Ireland.
<p><br></p>
<p class=""><strong>Strange Maps #974</strong></p><p><em>Got a strange map? Let me know at </em><a href="mailto:strangemaps@gmail.com">strangemaps@gmail.com</a><em>.</em></p>
A world of "goblin porn"
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTQ5MDExMi9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTY1MjQ1MzM1MX0.7Nt6e30kVePubmQk9r-JGt5vIUuH9MuLuRzTNjcyAFI/img.png?width=980" id="acfba" class="rm-shortcode" data-rm-shortcode-id="2e869701dc1f5a1bc69363de4125f6c9" data-rm-shortcode-name="rebelmouse-image" />The Known World, with Westeros top left. Image source: A Wiki of Ice and Fire / public domain
<p>Warning: if you haven't caught up, mild spoiler ahead.</p><p>"Hell is other people talking about <em>Game of Thrones</em>," <a href="https://www.theguardian.com/commentisfree/2019/may/14/i-dont-watch-game-of-thrones-which-makes-me-a-lot-more-interesting-than-you" target="_blank">writes Arwa Mahdawi</a> in <em>The Guardian</em> this week. A few days more, and the eighth and final season of the show she dubs "densely plotted goblin porn" — clearly, she's not a fan — will be over.</p><p>Meanwhile, hell is hard to avoid. When it comes to following GoT, I'm on Team Arwa (a.k.a. <a href="https://www.facebook.com/SLContentProvider/videos/10155869239233512/?v=10155869239233512" target="_blank">Team Stewart</a>) but even we have heard rumors about a sudden bout of genocidal mania, and Daenerys perhaps no longer being <a href="https://www.washingtonpost.com/business/2019/05/13/why-least-parents-may-be-having-regrets-after-last-nights-game-thrones/?utm_term=.5be533887eb0" target="_blank">such a good baby name</a>.</p><p>Fortunately for map nerds, GoT's dense plotting also extends to its topography. Just like the series' peoples, protagonists and events — often borrowed from actual history, then slightly altered — its fictional map is more than loosely based on ours.</p>Maps to frame fantasy
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTQ5MDEwNy9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTYzNDc2MDMwNn0.RWN-x_wlWjZm6N6SZ-m-M5JilodSGIOaRhsZ1XoRt30/img.png?width=980" id="a0a0f" class="rm-shortcode" data-rm-shortcode-id="c58983afcc622614e06589c42f56871a" data-rm-shortcode-name="rebelmouse-image" />The first part of Gulliver's Travels (1726) contained a Map of Lilliput and Blefuscu, showing the fictional islands positioned in the Indian Ocean, north-west of Van Diemen's Land (now Tasmania). Image source: British Library / public domain
<p>Fantasy locations have been a literary device at least since Plato spun his stories about <a href="https://bigthink.com/strange-maps/394-athanasius-kirchers-atlantis" target="_self">Atlantis</a>, back in the 4th century BC. From Plato only a description of the island survives, more recent tales of fictional geography came with a map: Thomas More's <a href="https://bigthink.com/strange-maps/51-a-colour-map-of-utopia" target="_self"><em>Utopia</em></a>, Jonathan Swift's Lilliput (and other islands visited by Gulliver), and Robert Louis Stevenson's <a href="https://bigthink.com/strange-maps/378-x-m-aarrrh-ks-the-spot" target="_self"><em>Treasure Island</em></a>. </p><p>The watershed fantasy map, the one that spawned a thousand imitations, is the map of Middle-Earth, <a href="https://www.countrylife.co.uk/out-and-about/focus-hand-drawn-maps-jrr-tolkien-launched-middle-earth-181987" target="_blank">created by J.R.R. Tolkien himself</a> (from the 1920s to the 1940s): as the endpapers to the <em>Lord of the Rings</em> trilogy, they framed the wanderings of the Fellowship, the movements of armies and heroes, and the deep history underlying the narrative. </p><p>"I wisely started with a map and made the story fit," Tolkien once quipped. George R.R. Martin did it the other way around: he envisaged the opening scene of the first book of <em>A Song of Ice and Fire </em>(the book series adapted as GoT) and built the tale — and the world around it — from there.</p>Not just a badly drawn Britain
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTQ5MDExNS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1NjAyNDMzN30.kyFri8hL3N-4bZbulzhawa0yDAONO_tfEi6eis1XOVI/img.jpg?width=980" id="c814e" class="rm-shortcode" data-rm-shortcode-id="2aa6bb52e9348162d213dc8a02da3ce5" data-rm-shortcode-name="rebelmouse-image" />Mighty Westeros side by side with tiny Britain. Image source: Imgur
<p>Only then did he take on the mantle of the First Cartographer, and it's his hand-drawn maps that appear in the books. Another similarity with Tolkien, whose <a href="https://bigthink.com/strange-maps/121-where-on-earth-was-middle-earth" target="_self">fantasy world was inspired by real geography</a> was that Martin also drew his world with one eye on the map of Europe, and especially the British Isles. </p><p>Most of the action, in the books and the series, takes place on the continent of Westeros (there is a whole Known World out there as well). There's an obvious parallel with Great Britain in the Wall in the North: at 700 feet high and 300 miles long, it is a clear extrapolation of Hadrian's Wall (a mere 73 miles long, and never higher than 20 feet). </p><p>Westeros is much bigger than Britain, though: about 3,000 miles from the Wall to the south coast, about six times the distance from Aberdeen to London. But Westeros is not just a badly drawn Britain, nor a mirrored version of its land mass (two popular theories). Things click into place — literally — if you do the following: </p><p>Take Ireland, turn it on its head, inflate it by about a third, and stick it to Britain's bottom (via a new land bridge called The Neck). And hey presto, there's Westeros.</p>Britain and Ireland, joined at the - ahem - south coast
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="c7ef3755e919b26847271564f3e9a260"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/ftc9rZIifYY?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>In fact, Martin admitted as much at the 2014 Comic–Con: "If you want to know where a lot of fantasy maps come from, take a look at any map in the front of your favorite fantasy book and turn it upside down. Westeros began as upside-down Ireland. You can see the Fingers at the Dingle Peninsula."</p><p>This has some implications for the (presumed) parallels between locations in Westeros on one side, and Britain/Ireland on the other. For instance, King's Landing, the capital of Westeros, corresponds to Galway rather than London. </p><p>But such correspondences are futile. Each borrowing from actual history and geography is given a little twist, so people can argue until they're blue in the face whether the Red Wedding was inspired by the St. Bartholomew Day's Massacre or by the Black Dinner, whether the Dothraki are the Huns or the Mongols, and if Winterfell is Manchester or Leeds. </p><p>For some, King's Landing is reminiscent of old Constantinople. In the TV series, the old walled cities of Mdina (Malta) and Dubrovnik (Croatia) stand in for the capital. And Martin himself dreamt up the teeming city remembering the view of Staten Island from his childhood home in Bayonne, New Jersey. </p><p>For some, that tension with "real" history and geography adds a layer of enjoyment to GoT. Team Arwa can feign interest in a cartographic discovery that hardcore fans have made years ago, and will be happy only when the last dragon has finally landed. <br> <br></p>
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