GEOL 1 Lecture Notes - Lecture 18: Subduction, 2004 Indian Ocean Earthquake And Tsunami, Types Of Volcanic Eruptions
Document Summary
Thailand/indonesia/other countries, - many people died (250k+) A long wave that moves the entire depth of the ocean. Experienced on shore as a series of rapid surges flowing for many minutes. Cause: any disturbance on seafloor that displaces a large water mass (push aside the water in the ocean) Most tsunamis generated by subduction zone earthquakes. Water ruptures upwards then waves form and spread after quake. Volcano collapses on itself and causes explosive energy. Move the entire depth of the ocean (often several kilometers deep) Travel at speeds from 500 to 1000 km/h (315-625 mi/h) Shallow waters: water piles up at wave front. Speed slows to 72 km/h (45 mph) Long wavelength = onshore flow for several minutes. There will be several surges of varying heights over many hours. Shape of island and seafloor focuses tsunami in hilo. 159 people, including many school children, killed. Led to formation of pacific tsunami warning center.
