Tuesday's earthquake in Christchurch has triggered a massive disturbance, known as a calving, on the Tasman Glacier at Aoraki Mount Cook.
The shallow 6.3-magnitude quake struck at 12.51pm, 10km south-east of the central city, causing many deaths and widespread devastation.
The glacier's terminal face was thrust about 60 metres above the level of the Tasman Lake, causing a 30 million tonne iceberg to break away from the Glacier.
The general manager for tourism at Aoraki Mount Cook Alpine Village, Denis Callesen, says it was a superb example of nature in action and a guest on a boat trip to the glacier captured the event on camera.
The Hermitage Hotel base camp is unaffected by the quake and it is working with the tourism industry to ensure rooms are available for visitors who had been scheduled to stay in Christchurch, he says.