字幕表 動画を再生する 英語字幕をプリント The Earth's surface is shaking; long cracks split the ground open; lava rivers are rapidly flowing down the slopes; explosions sound more and more often; rocks and other debris are flying into the air; the sky is darkened by the clouds of ash. Nah, it's not a plot of a new disaster movie! It's just geologists who decided to drill into a super-volcano. But before I tell you about all this drilling, let me introduce you to super-volcanoes that can produce super-eruptions! And when they do, they blow more than 240 cubic miles of ash, molten rock, and hot gases up into the air. In other words, four super-eruptions could fill the Grand Canyon to the brim! Super-volcanoes get formed when gigantic volumes of scorching hot magma are trying to escape from deep underground. It rises close to the surface but can't break through the Earth's crust. That's why at a depth of only several miles, there gathers a huge pressurized pool of bubbling magma. The pressure keeps growing because more and more of it is trying to get to the surface. Until - bang! - a super-eruption occurs! The most recent super-eruption took place in New Zealand. Well, when I say "recent," I mean around 26,500 years ago. That's when a super-volcano beneath the surface of Lake Taupo blew more than 300 cubic miles of ash and pumice into the air. Imagine 500,000 Great Pyramids of Giza flying up at the same time — that's how incredibly powerful that eruption was! But the most exciting and confusing thing about the eruption was that the Taupo volcano didn't simply explode like many others. Everything was going as usual at first: more than 200 square miles of magma had built up under the surface, and the pressure was getting higher and higher. But after the rock cracked, and the first portion of lava rushed out of the crater, something went wrong, and the super-volcano took a break! Only several months later, the disastrous explosion shook the ground, and thousands of tons of lava, rocks, and ash erupted high into the atmosphere. The unusual pattern of Taupo still confuses scientists to no end. But the age of super-volcanoes isn't over. The most infamous of them all is probably the one in Yellowstone National Park. This giant is responsible for at least three ginormous eruptions and who knows how many smaller ones! If this monster erupted anywhere as strong as it did 2.1 million years ago, it would spit out more than 600 cubic miles of red-hot stuff! You can probably picture it more vividly if I tell you that this volume is the same as 65,000,000 Capitol Rotundas in Washington, D.C. crammed together. That’s a lot of politicians! Anyway, scientists are sure that Yellowstone doesn't present any danger these days: for an eruption to happen, magma inside has to be at least 50% molten. With Yellowstone, this number is just 5 to 15 %. But of course, Yellowstone isn't the only super-volcano on our planet. New Zealand's Taupo you already know about, Japan's Aira Caldera, California's Long Valley, Indonesia's Toba — any of them can one day entertain us with a super-eruption! There are also several so-called super-volcanoes that haven't lived up to this name yet because they've never produced anything like a super-eruption. For example, in 1883, Indonesian volcano Krakatoa started to erupt. The power of it tore the volcano's walls open, and cold seawater rushed into its molten insides. The difference in temperatures made the volcano explode with a deafening boom which was clearly heard 3,000 miles away in Australia! It earned the blast the title of the loudest sound in history. But even though the consequences of the eruption were truly disastrous, it still wasn't powerful enough to be called a super-eruption. By the way, if you've ever seen a volcanic eruption, tell me all about that in the comments below! We’d lava hear all about it! ha Anyway, what devastates scientists the most is how little they know about super-volcanoes. Because those aren't just some overgrown fire mountains — no, they are way more complicated than that. Appearing so deep underground and extending for hundreds of miles, super-volcanoes don't follow the ways of all others. Experts are still unsure about the processes that trigger them, especially since super-eruptions (thankfully) don't take place more often than every 50,000 years or so. That's one of the reasons why some experts want to drill into a super-volcano. It would allow them to collect samples and examine geothermal energy that's rising from the heart of a volcano. It could help to understand "if" or "when and how" a super-volcano might burst. It's not the only reason why drilling into one may be a good idea. Another daring project includes making a 6-mile-deep hole that would reach the belly of a super-volcano and pump down cold pressurized water. It's supposed to nail two birds with one stone: cool the volcano down and produce green energy! By the way, don’t throw stones at birds. It’s not nice. Anyway, see for yourself: when the water got back from the drill hole, its temperature would be around 662°F. If there was a geothermal plant built anywhere near that place, the water could be used to generate loads of electric power. The whole process would be very simple, that's why such electric power would cost only $0.10 per kWh. What's more, thanks to this technology, engineers would slowly but surely extract the heat from the volcano, minimizing the risk of a super-eruption. Sounds great but is it indeed? Even though the idea of drilling a hole in a super-volcano seems to have its own benefits, many physicists, geologists, and even politicians have their doubts. Let's say, you don't drill too deep into the volcano — just deep enough to get some materials to examine. It's supposed to be safe since you just need some rock samples, and you aren't going to tamper with the insides of this nature-made cauldron with magma. But what's happening in reality is you getting inside a cage with sleeping lions and trying to steal their food. I mean you can get away with this crazy fit. Or one of the lions can wake up... The same will be going on with a super-volcano. It's true that if you keep drilling at the surface, you won't do any harm. But once you go a bit deeper or hit a hypothermal pocket, get ready for a calamity. It will release gases that are very likely to cause a series of super-powerful explosions. In the worst-case scenario, it may even trigger a full-blown volcano eruption! And you already know what the results of such an event can be: from fountains of lava and avalanches of molten rocks to climate changes all over the globe! But what if you decided to drill even deeper in an attempt to cool the volcano down or to release the pressure inside and prevent the thing from blowing? It would be even riskier! For example, you drill and drill and accidentally hit a magma chamber! Then, while trying to cool down the volcano with water, you make the top of the magma chamber way more fragile than it used to be. It results in the whole structure being ready to collapse at any moment. Or your drilling may lead to the release of toxic gases that tend to accumulate at the top of the magma reservoir. And at the moment you let these gases out by mistake, you'd better be wearing a full face breathing mask! Of course, you could avoid such dramatic consequences if you decided to drill somewhere away from the center of the super-volcano. But once again, these fellows are super-unpredictable, and nobody can figure out their patterns with iron-clad certainty. That's why the drilling isn't going to happen until its necessity starts to overweigh all the risks. Let sleeping dogs lie, you know? In 2006, the world's largest mud volcano Lusi in Indonesia erupted, sending tons of boiling water, gas, and mud in the air. More than 30,000 people had to leave their homes and relocate. And the volcano still isn't done with spewing out mud! Some experts claimed that the reason for the disaster was nearby oil drilling that could provoke the eruption. On the other hand, the trigger could be an earthquake that happened 175 miles away. You never know with volcanoes . Hey, if you learned something new today, then give the video a like and share it with a friend! And here are some other videos I think you'll enjoy. Just click to the left or right, and stay on the Bright Side of life!
B1 中級 火山に穴を開けたら? (What if You Drilled into a Volcano) 11 0 林宜悉 に公開 2021 年 01 月 14 日 シェア シェア 保存 報告 動画の中の単語