Презентация, доклад по теме Природные катастрофы для 8 класса

concussions of earth surface. They can be related to volcanic activity or with motions of sial flags and their parts.
A center of earthquake can be deeply under a terrene - on a depth to a few hundreds kilometres, in this case on a surface they are felt poorly enough. Those earthquakes that take place on a depth a 20-50 km have a most destructive capacity

gravitational waves arising up as a result of change upwards or downward extensive areas of sea-bottom at submarine and off-shore earthquakes. Speed of distribution from 50 to 1000 км/час. Height in area of origin a from 0,1 to 5 m, at a coast is a from 10 to 50 m and higher.

up in a кучево-дождевом (thunderstorm) cloud and spreading downward, often to the terrene, as a cloudy sleeve or trunk by a diameter in ten and hundreds of meters[1]. Development of tornado from a cloud distinguishes him from some outwardly similar and also different by nature phenomena, for example смерче-вихрей and dusty (sandy) whirlwinds. Usually the transversal diameter of crater of tornado in a lower section makes a 300-400 m[2], although, if a tornado touches the surface of water, this size can make an only 20-30 m, and at passing of crater above dry land can arrive at a 1,5-3 km