A tsunami is a series of waves caused by earthquakes or undersea volcanic eruptions
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On Nov. 18, 1929, a magnitude seven.4 Mw earthquake occurred one hundred fifty five miles south of Newfoundland on the southern fringe of the Grand Banks, Canada. This illustration, referred to as a wave Time Travel Map, shows the arrival times of wave waves. Red: 1-4 hour arrival times; Yellow: 5-6 hour arrival times; Green: 7-14 hour arrival times. The map was made by government agency and therefore the International wave info Center. read additional wave Time Travel Maps(http://www.ngdc.noaa.gov/hazard/tsu_travel_time.shtml).
Tsunamis square measure large waves caused by earthquakes or volcanic eruptions beneath the ocean. go in the depths of the ocean, wave waves don't dramatically increase tall. however because the waves travel interior, they build up to higher and better heights because the depth of the ocean decreases. The speed of wave waves depends on ocean depth instead of the space from the supply of the wave. wave waves might travel as quick as jet planes over deep waters, solely retardation down once reaching shallow waters. whereas tsunamis square measure typically observed as recurrent event waves, this name is discouraged by oceanographers as a result of tides have very little to try to to with these large waves.