Bjørn Gjevik (Matematisk institutt): "Large Destructive Waves from Earthquakes and Slides"

Long water waves (tsunami) with typical wavelength 1-100 km and period 1-15 minutes are generated by earthquakes, submarine slides or rock slides from steep mountain sides, explosive volcanic activity and meteorite impacts. The waves can propagate over long distances, amplify when approaching shallow water at the coast, and penetrate long distances inland. Historic accounts include a large number of destructive events with loss of many lives and extensive property damage. In the seminar the mechanism of wave generation, propagation over large distances, amplification and run-up at the coast will be discussed particularly in relation to the recent tsunami event in The Indian Ocean. Results of model simulations of tsunami events will be presented with computer generated animations of wave fields. The possibilities for establishing warning systems and precautions to reduce the damage will also be discussed.