"Ready To Blow" - National Geographic's Guide To The Yellowstone Supervolcano
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Amid a growing 'swarm' of over earthquakes (now over 1000), and Montana's largest quake ever, scientists are growing increasingly concerned that the so-called 'super-volcano' at the heart of Yellowstone National Park could be building towards a Category 7 eruption. So what is a 'super-volcano' and what does its explosion mean for life on earth? NatGeo explains...