A tsunami is a series of large sea waves generated by earthquakes, underwater landslides, or delta slope failure. The waves can kill and injure people and cause great property damage. The first wave is often not the largest; successive waves may be spaced many minutes apart and may continue for many hours.
The 1964 Alaskan earthquake triggered a tsunami that affected sea levels as far away as California, causing 10 deaths and approximately $15 million in damage in Crescent City from a 21-foot wave.
Image courtesy of University of Southern California Tsunami Research Group.
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