![]() The explosions were so loud, they could be heard nearly 3,000 miles away on Rodriguez Island, and they triggered towering tsunami waves that killed more than 36,000 people. Take Krakatau's 1883 eruption for example. Several volcanoes are commonly called “supervolcanoes” but their eruptions haven't quite earned them this super status. This latter supervolcano is the last to have ever released a super-eruption, which burst free some 26,500 years ago. There are many supervolcanoes around the world other than Yellowstone, including California's Long Valley, Japan's Aira Caldera, Indonesia's Toba, and New Zealand's Taupo. Photograph by Russell Pearson, Barcroft Images/ Barcroft Media/ Getty What other volcanoes are “super”? Although a lava flow can pose hazards for communities that lie in its path or spectators attempting to approach close enough to roast a marshmallow, those dangers are much easier to predict and avoid.Ī hot spring steams and bubbles in Yellowstone National Park, the surface manifestation of the caldera simmering below. More likely than such an explosion is a lava flow-a spurt of slowly oozing molten rock. ![]() An eruption usually requires at least 50 percent to gel in this gooey hot state. The magma lurking in Yellowstone's shallow reserve is between just 5 and 15 percent molten. While such an eruption in the distant future is possible, the probability of it happening in the next few thousand years is “exceedingly low,” according to the USGS. The film depicted what would happen if the volcano erupted again with a magnitude as large as its blast some 2.1 million years ago, which produced roughly 588 cubic miles of material. While the unfounded fear in a pending Yellowstone eruption has swirled for decades, the BBC and Discovery's 2005 docudrama forever tied the volcano to its super-moniker. This geologic superstar has had at least three very large eruptions in its history: Two are super-eruptions that were VEI 8 (some 2.1 million and 640,000 years ago), and one eruption 1.3 million years ago was VEI 7, producing around 67 cubic miles of material. Yellowstone is now perhaps the most famous of the world's volcanoes that have produced VEI 8 eruptions. While the term still elicits eye rolls from many volcanologists, its popularity in the media has forced "supervolcano" into scientific realms. But it seemed to truly launch into the stratosphere after the 2000 BBC/Horizon documentary Supervolcanoes, and was subsequently buoyed by a 2005 docudrama created by the BBC and the Discovery Channel about the now infamous Yellowstone supervolcano. Instead, many early citations used “supervolcano” in reference to an amalgamation of multiple volcanoes.īy the late 1900s, the term was picking up steam. Klemetti, who now writes for Discover, notes that the initial geologic use of the term in the mid-1900s differs from its modern definition of a mega-eruption. Since then, the term has taken a winding path to popularity. It was used as far back as 1925 in the travelogue Conquering the World, by Helen Bridgeman. (There's a little wiggle room in the number, because when judging historical events, it's difficult to estimate the extent of ejected material.) Where did the term supervolcano come from?Īccording to an investigation by volcanologist Erik Klemetti for Wired, the origins of the term “supervolcano” are far from scientific. While dozens of volcanoes may be erupting around the world on any given day, scientists have identified just 42 eruptions that ranked a VEI 8 (or high 7) in the last 36 million years. For the some 5,000 eruptions with an assigned VEI that took place during the last ten thousand years, not a single one ranked a VEI 8, according to the USGS. What's more, very few volcanoes reach such a super-status. But there's an important caveat about supervolcanoes that most people commonly overlook: Just because a volcano has had a super-eruption once or even twice in its past doesn't mean its future eruptions will be just as big. These are very large eruptions, the impacts of which would be widespread-from avalanches of hot rock and gasses racing down the volcano's flanks to global changes in climate. That places it at a magnitude of eight, the highest ranking on the Volcanic Explosivity Index, or VEI, which is used to measure the explosiveness of an eruption. Though massive eruptions do pose real dangers, misconceptions about them abound.Īccording to the United States Geological Survey, a volcano is considered “super” if it has had at least one explosion that released more than 240 cubic miles of material-a little more than twice the volume of Lake Erie. Supervolcanoes are like the supervillains of the geologic world, as stories of their looming threat grow ever more exaggerated.
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