Argentine glacier makes a splash

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STORY: Huge ice chunks broke off the Perito Moreno glacier in Argentina's Patagonia on Friday, putting on a spectacular show in the glacier's cyclical pattern.

The glacier, a massive tongue of ice in the Rio Gallegos province that covers 97 square miles, advances yearly into a lake, known as Lago Argentino.

As Perito Moreno moves forward, it cuts off a river feeding the lake. Water builds up pressure and slowly undermines the ice, forming a tunnel until ice comes tumbling down.

The phenomenon repeats itself at irregular intervals, with the last major ice falls occurring in 2008.