Electrocution: New Way to Erode Mountains [View all]

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http://www.livescience.com/40701-lightning-strikes-erode-mountains.html

Boom, zap, pow! Who needs superheroes to move mountains, when lighting does the job just fine?

Powerful explosions sparked by lightning create piles of angular, jumbled rocks atop mountain summits, a new study shows. The frequent blasts break down high peaks more quickly than frost-shattering — when freezing water wedges apart fractured rock.

In Lesotho's Drakensberg mountains, a single lightning bolt can blow out 100 to 350 cubic feet (3 to 10 cubic meters) of bedrock, said Jasper Knight, lead study author and a geomorphologist at Wits University in South Africa. The sheer volume of summer lightning strikes atop high peaks, combined with their massive erosive power, means electric blasts are a long-overlooked force in bringing down mountains, Knight and his co-author conclude.

"Lightning is very significant in causing landscape erosion and the formation of lots of fractured bedrock," Knight told LiveScience's OurAmazingPlanet. "What I think this project does, in highlighting the role of lightning, is go some way toward overturning a very entrenched and long-held paradigm of how many continental scale landscapes have evolved." [Electric Earth: Stunning Images of Lightning]