Earthquakes
- Рубрика: Презентации по английскому языку
- Просмотров: 260
Презентация "Earthquakes" онлайн бесплатно на портале электронных презентаций school-present.com
The vertical motions lead to a drastic lowering or raising of the rocks. Typically, the offset is only a few centimeters, but the energy released when moving billions of tons of rock, even a small distance is enormous.
This sudden release of energy stored in compressed or stretched rocks. It manifests itself in tremors and vibrations of the earth's surface.
The second reason reflects deeper processes occurring in areas along the edges of the shifting plates, where the edges of these masses are immersed in the Earth's crust Earth's mantle at depths of about 500 km re-absorbed, absorbed. For this reason, there are already more major earthquakes
Irishman Robert Mallet distinguished engineer has made a significant contribution to the study of earthquakes. He found that there are certain zones where occur most frequently small or large earthquake. Mallet mapped the areas in which seismic waves propagate, we found that all of them, like rays from the star, emanate from a single point - the epicenter located at the ground surface above the earthquake
The first seismograph, which had scientific value, was built in 1879 in Japan, Ewing. As the cargo was for a pendulum cast iron ring weighing 25 kg, suspended on steel wire.
Currently, inducted into the practice of monitoring large areas: near the major faults are placed devices on which information is transmitted via satellite connection to the centers, where is processed.
Другой метод основан на определении содержания воды в породах. В напряжённых породах происходит увеличение объёма пор, а тем самым и водосодержания. Издавна известно, что люди использовали более чутких животных для предупреждения о возможной опасности.
Not bad a presentiment of natural disturbances and attack pets. It is well known that dogs, chickens and pigs shortly before the onset of disasters are changing their behavior, give in to apathy and refuse to eat. .
. Snakes, especially poisonous, in anticipation of an approaching earthquake is a few days leave the inhabited burrows. So do lizards and ants. Some scholars are inclined to explain this undeniable fact highly sensitive to temperature changes in the skin of the soil
As part of the ESP is not inferior to reptiles and crocodiles. December 17, 1987 on the island of Kyushu, dozens of individuals have begun to publish an alarming growling and bending arch, perform an intricate dance.
A new type of earthquake, Japanese scientists discovered. Earthquake, described by researchers led by Professor Ito Iosihiro have ultra-low frequency. Identified seismic processes can lead to fluctuations in the magnitude 3 to 3.5 points. However, the shocks are so slow that their man does not feel. However, these variations contribute to the growth pressures in a seismically active zones.