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Lisa Mullins: The earthquake that hit Christchurch had a ripple effect more than 100 miles away, a jaw-dropping one. When the ground shook, a 30 million ton chunk of ice broke off the mighty Tasman Glacier. It's the largest glacier in New Zealand and it sits on Tasman Lake. It draws tourists galore, some of whom happened to be on a pontoon boat on the lake just as the mountain of blue ice broke off the glacier. The chunk of ice was about three quarters of a mile long, about 250 feet wide. One of the skippers on the lake at that moment was Mark Bascand, he works for Glacier Explorers, that's the company that takes tours out onto the lake. He and his passengers were on the South end of Tasman Lake when the ice suddenly broke away, a process known as calving.
Mark Bascand: We looked up and to the North side we could see the glacier had broken off and a massive calving had come down. And you could see the mist of all the water and the ice just flying up into the air, and that lasted for quite a while, maybe a good sort of half an hour or so. And then it slowly started to settle, and then we could see this amazing blue ice that had calved off the glacier and was lying in the lake there.
Mullins: Although Mark Bascand and his passengers were pretty far from where the ice plunged into the lake, he said the intense blue color of the ice enabled them to see it after it slipped into the water. But the sight of the ice breaking off is what he'll remember most.
Bascand: That was probably the most incredible thing to see just like a massive white cloud coming into the lake for a good moment or so, it just crashed into the lake, and started to break up and firing ice and water everywhere.
Mullins: In fact, the ice crashing into the water sent 10 foot high swells down the lake, especially around the site of the boat. He called it a tsunami. Mark and his boat and passengers were lucky enough to be safe in the middle of the lake.