Tsunami's

            Tsunami- is a series of castrophic ocean waves of volcanic origin generated by earthquakes, volcanic eruption, and landslides beneath the ocean floor. They are the world's most powerful wave. They are not generated by gravitational pull coming from the sun or moon. Due to the height only being a few meters high and the length being able to spread over 750 kilometers tsunami's can go undetected until they reach shallow waters along the coast. They are said to be un-harmful in deep waters. .
             There are three physical processes that develop tsunamis. Generation, propagation, and inundation. Generation is caused when there is a disturbance on the ocean floor like fault movements. Fault movements can help with the interpretation of the seismic data being collected. Propagation is the transport of seismic energy away from the quake/fault through wave movements. At this point a wave linear theory is applied. This theory helps to predict the wave depth and length, which helps to determine the speed of tsunami. During this point the wave direction can change and conversion can occur on the sea floor. The final process is inundation when a tsunami comes ashore as a breaking wave. When this occurs the height of the wave is so large that linear theory can no longer account for the interaction between the water and the shoreline. When this happens flooding can occur inland causing major damage.
             Tsunami's have occurred and caused serious damage and harm in several parts of the world mostly in the Pacific Ocean Rim. Within the past 10 years 10 tsunamis have taken over 4,000 lives. These disasters have occurred in Nicaragua and Papua New Guinea, Hawaii and believe it or not Alaska. One of the most recent tsunamis to occur was that of in Papua New Guinea in the many villages of Sissano, Arop, Warapu and other villages in between the Sissano Lagoon. This disastrous tsunami happened a little over two years ago on July 17, 1998.