Spectacular glacier collapse wows spectators in Argentina

A lucky group of visitors to Argentina's Los Glaciares National Park were treated to a spectacular and dramatic sight when the famous Perito Moreno Glacier collapsed this week.

The Los Glaciares National Park, a Unesco World Heritage Site, is highly recommended for anyone stopping off in Argentina on an overland South America tour and provides some of the most breathtaking scenery anywhere in the world.

Perito Moreno Glacier is probably the most famous glacier in the park thanks to its size and accessibility and seeing the natural wonder up close is a memorable experience at any time.

But on Sunday (March 4th), a huge ice dam that is a key feature of the glacier collapsed into a lake 60m below after numerous chunks broke off over the previous seven days, in one of nature's most awe-inspiring displays.

The phenomenon is something that occurs every few years, with the last occasion being in 2008.

Flowing at a rate of 1.7m a day, the Perito Moreno Glacier repeatedly advances into Lake Argentina, cutting off the river-fed side of the lake every three to four years and forming a giant ice dam.

As the water pressure gradually builds up behind the dam, it places increasing force on the ice until it eventually collapses in an event known as an ice rupture.

According to the Telegraph, some 2,500 tourists lined up at observation decks and cheered as the ice splashed into the water, while AFP reports that the ice created a crash heard several kilometres away.

"The noise was very great, it was coming down in buckets," park ranger Carlos Corvalan told the news agency.

Perito Moreno is one of the largest of the 47 glaciers in the Southern Patagonian Ice Field, covering 97 square miles, and is one of only three Patagonian glaciers that is still growing.