A huge vertical slab calved off the front of New Zealand’s longest glacier, the Tasman Glacier, into Tasman Lake after the 6.3-magnitude quake hit Christchurch on 22 February. The chunk is estimated to have been 12m long by 75m wide, scientists say. The iceberg’s collapse also kicked up 3.5-m waves in Tasman Lake. “We heard a large crack like a high-powered rifle,” an American tourist who had been on a glacier tour at the time told the New Zealand Herald. Even before the earthquake, tourist guides were already being cautious about not approaching the glacier too closely, due to heavy rain in past weeks.