There are some programs, like the ones that are broadcast at National Geographic Channel, where professionals show us on many opportunities documentaries about earthquakes and the amount of damage that they had produced in some areas. But… what is an earthquake? We can define them as the shaking of the Earth’s surface caused by the rapid movement of the Earth’s rocky outer layer. In addition, earthquakes results from two main factors and can have two harmful effects.
There are two main causes of seismic tremors. One of them is fault rupture. The faults slip because of movement of the Earth’s tectonic plates. Because of the pressure within the crust increases slowly over hundreds of years and finally exceed the strength of the plates, earthquakes take place. Human activities can also be the cause of significant earthquakes. Human beings carried out many activities that increase stress in the earth’s crust which lead to earthquakes. For example, injecting fluid into deep wells for waste disposal, filling reservoirs and firing underground nuclear test blasts. Since the tectonic plates and humans activities, seismic tremors take place.
Earthquakes can mainly have two dreadful effects. First, one direct effect of earthquakes is ground shaking and landslides. The earthquake’s waves make the ground move, shaking buildings and causing weaker structures to collapse. The damage of properties can lead to secondary effects such as fire, which is produced because of the rupture of natural gas mains and water lines. Second, other post-earthquake threats are tsunamis. In many cases, the slip fault is located beneath the sea which can produce tsunamis. Tidal waves wash ashore and water moves inland, causing severe flooding, the loss of lives due to drowning and damage to property.
To conclude, there are two main reasons as well as consequences of earthquakes. Although we can prevent earthquakes, there are some measures we can take to reduce the damage that they caused. I think that it is important to be concerned about this topic because we never know whether we can be victims of an earthquake.
Earthquakes Essay examples
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What is an Earthquake?
An Earthquake is the shaking of the earth's surface caused by rapid movement of the earth's rocky outer layer. The sudden shaking of the ground that occurs when masses of rock change position below the Earth's surface is called an earthquake. The shifting masses send out shock waves that may be powerful enough to alter the surface of the Earth, thrusting up cliffs and opening great cracks in the ground.
Earthquakes, called temblors by scientists, occur almost continuously. Fortunately, most of them can be detected only by sensitive instruments called seismographs. Others are felt as small tremors. Some of the rest, however, cause major catastrophes. They…show more content…
Although it is certain that violent Earth tremors in themselves are destructive, there are often other kinds of Earth movements that are triggered by earthquake shock waves. Thus, the violent shaking that accompanies many earthquakes often causes rockslides, snow avalanches, and landslides. In some areas these events are frequently more devastating than the Earth tremor itself.
Floods and fires are also caused by earthquakes. Floods arise from tsunamis along coast lines, from large-scale seiches in enclosed bodies of water such as lakes and canals, and from the failure of dams. Fire produced the greatest property loss following the 1906 San Francisco earthquake, when 521 blocks in the city center burned uncontrollably for three days. Fire also followed the 1923 Tokyo earthquake, causing much damage and hardship for the citizens.
Most of the worst earthquakes are associated with changes in the shape of the Earth's outermost shell, particularly the crust. These so called tectonic earthquakes are generated by the rapid release of strain energy that is stored within the rocks of the crust, which on continents is about 22 miles thick. A small proportion of earthquakes are associated with human activity. Dynamite or atomic explosions, for example, can sometimes cause mild quakes. The injection of liquid wastes deep into the Earth and the pressures