The largest island in a lake on an island in a lake on an island is a nameless 1.6-hectare (4-acre) island at 69Â°47â²35â³N 108Â°14â²28â³W / 69.793Â°N 108.241Â°W / 69.793; -108.241, 121 kilometres (75 mi) inland from the south coast of Victoria Island, Canada.
A tsunami can travel across the open ocean at about 500-miles per hour, the speed of a jet airliner. As the wave approaches land and as the ocean shallows, the wave slows down to about 30 miles-per-hour and grows significantly in height (amplitude).
â¢ When the ocean is deep tsunamis can travel unnoticed on the surface at speeds up to 500 miles per hour (800 kilometers per hour), crossing the entire ocean in a day or less. Scientists are able to calculate arrival times of tsunamis in different parts of the world based on their knowledge of when the event that generated them occurred, water depths, and distances.