It's remarkable that the tsunami sent a wave halfway around the world to shake free such a massive block of ice. NASA says that the swells of water swarmed toward an ice shelf in Antarctica, 8,000 miles away. It took about 18 hours for the waves to reach Antarctica. According to historical records, this particular piece of ice hadn't budged in at least 46 years before the tsunami came along.
NASA via AP
Chunks of ice - twice the surface area of Manhattan - break away from the Sulzberger Ice Shelf on March 16, 2011, following the Japan earthquake and resulting tsunami that occurred on March 11, 2011.