Volcano facts to blow your mind
■ TRAGEDY has struck in New Zealand after a volcano blew its top killing at least six people. A rescuer has described the scenes at the White Island volcano – the country’s most active – as like something out of “the Chernobyl series”. JAMES MOORE reveals 15 things fascinating facts about volcanoes…
1 Volcanoes are openings in the earth’s crust through which molten rock called magma rises. They have been erupting for billions of years and created 80% of the planet’s surface.
2 An eruption is usually triggered by movement in the Earth’s tectonic plates or things such as glacial melting.
3 The word volcano comes from the name of the Roman god of fire – Vulcan, while the word lava is given to magma when thrown out by the volcano.
4 Volcanoes also throw out rock and super hot ash and gas, with deadly pyroclastic flows of volcanic matter able to move at 430mph.
5 Dome-like shield volcanoes, such as Kilauea in Hawaii which has been erupting continuously since 1983, have slow lava flows.
6 But cone-shaped stratovolcanoes often erupt violently – throwing ash far into the sky. A famous one was Krakatoa in Indonesia which erupted in 1883, causing a tsunami that killed 36,000 people.
7 The deadliest ever eruption was of nearby Mount Tambora in 1815, which sparked a volcanic winter and famine. Some 71,000 people died from its effects.
8 Mount Vesuvius near Naples, Italy, exploded in AD79. It buried the towns of Pompeii and Herculaneum and killed 16,000 people. It had 100,000 times
the energy of both atomic bombs dropped on Japan in World War Two.
9 Other famous eruptions include 1980’s Mt St Helens in the US which destroyed 230sq miles of forest and Mt Pinatubo in 1991 in the Philippines which killed 700. Plumes of ash from the 2010 eruption of Eyjafjallajökull in Iceland grounded thousands of flights.
10 An estimated 100million people visit volcanic sites annually including Europe’s largest active one, Mount Etna in Sicily. Nearby Stromboli erupted this July, killing a hiker.
11 There are about 1500 active volcanoes worldwide, most in the so-called Pacific Ring of Fire. This includes New Zealand’s White Island volcano.
12 A volcano erupts somewhere every 12 hours, with 5% of the globe’s population living in danger zones.
13 A super-eruption occurs around every 50,000 years. The last one was 75,000 years ago and probably triggered the Ice Age. If America’s Yellowstone National Park supervolcano explodes it could kill 10% of the world’s population.
14 Some fall dormant, while others go extinct like Britain’s Ben Nevis.
15 The world’s largest volcano is Mauna Loa, covering half the island of Hawaii, but the biggest in the Solar System is Olympus Mons on Mars – 13 miles high, three times Mount Everest.