Tsunamis – Scourge of the Pacific
Although tsunamis occur most often in the Pacific Ocean, they can be generated by major earthquakes in other areas. The most frequent cause of tsunamis…is crustal movement along a fault: a large mass of rock drops or rises and displaces the column of water above it. This column of water – a tsunami – travels outward from the source at the fantastic speed of 500 mph or more. When an earthquake occurs in the Pacific Ocean Basin, authorities must quickly decide on a course of action.
Earthquake Information Bulletin (USGS)↗