{"id":507,"date":"2010-09-07T12:04:15","date_gmt":"2010-09-07T02:04:15","guid":{"rendered":"https:\/\/scienceillustrated.com.au\/blog\/?p=507"},"modified":"2010-09-07T12:41:10","modified_gmt":"2010-09-07T02:41:10","slug":"the-worlds-most-beautiful-and-deadly-volcanoes","status":"publish","type":"post","link":"https:\/\/scienceillustrated.com.au\/blog\/features\/the-worlds-most-beautiful-and-deadly-volcanoes\/","title":{"rendered":"The world’s most beautiful, and deadly, volcanoes"},"content":{"rendered":"
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Image: Olivier Grunewald <\/p>\n<\/div>\n

More than 1,500 ground-rumbling, lava-spewing \u2014 and stunning \u2014 volcanoes dot the planet, changing their surroundings and renewing resources as they go. <\/strong><\/p>\n

At any given moment, about 20 volcanoes are erupting. Some wipe out nearby cities, like Italy’s Mount Vesuvius did to Pompeii in A.D. 79, and others erupt in desolate regions, like the farthest ends of Siberia. But not all volcanoes are towering, rock- and ash-spewing behemoths like Vesuvius; some are long, lava-effusing fissures on the ground, and many lie dormant, no longer trembling or exuding any debris at all.<\/p>\n

Building a mountain<\/strong>
\nVolcanoes form around vents on the Earth’s surface that tap into pools of magma gathering beneath. As lava pours out of the openings, it cools and hardens, forming a rocky cone that grows with each bout of activity. The most common formations are recognisable, steeply conical mounds called stratovolcanoes. Low and broad versions, known as shield volcanoes, build slowly from fluid lava flows that travel longer distances before hardening. When pressure from gases and magma builds and volcanoes erupt, they can produce more than lava. The most deadly result is a pyroclastic flow, a mixture of superheated gas and rocks that can travel at 725 kilometres per hour. Volcanic material can mix with water, snow or ice to form lahars, speeding mudflows that are also highly destructive.<\/p>\n

Eruptions can leave small recesses, or craters, on the summit or sides of a volcano. A powerful blast can empty a magma chamber, collapsing the ground and leaving behind a huge crater, or caldera. When the danger ends, though, the minerals that were brought to the surface can help sustain new vegetation and growth. Active volcanoes represent the endless and mysterious reserves of Earth’s power. “I’m always disappointed when I’m on a mountain that isn’t a volcano,”\u009d says John Eichelberger of the US Geological Survey, who has studied volcanoes for almost 40 years. “It’s just a big hunk of rock.”\u009d<\/p>\n

See more: <\/strong>Click on the images below to launch our stunning image gallery.<\/p>\n

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