World’s largest tsunami debris
House-sized boulders were ripped from a reef, then washed 100 meters or more inland
All evidence hints that the boulders, which lie inland of a three-kilometer stretch of coastline, are out of place, says Matthew J. Hornbach, a geologist at the University of Texas at Austin. First, the island is flat, so the immense boulders — each of them weighing more than 46 metric tons — didn’t roll to their current positions more than 100 meters from the beach. Second, the boulders’ composition differs significantly from the island’s volcanic soil, but matches that of the coral reef found just offshore, he notes.