EARTH QUAKES TRIGGERED BY HUMAN ACTIONS

Earth Quakes Triggered By Human Actions

Earth Quakes Triggered By Human Actions

Earth Quakes

Earthquakes are the natural disasters that shake the earth and sometimes raise the oceans. They do not all have the same intensity. The Richter scale measures the magnitude of earthquakes (2-9) and can be classified according to the energy they release.

The crust is made up of giant plates that move beneath the continents and oceans. Faults separating the plates. On the globe, the areas most at risk for earthquakes located near these faults. The plates are not fixed; they travel continuously relative to each other. Very quietly, they graze and grow. The rock forming the crust is stretched, but they have their limits. When the crust is too stretched, it breaks it is this break which causes earthquakes. The movements are sideways and are very destructive.

The consequences of an earthquake depend on its amplitude. Previously, we used the Mercalli scale is more subjective because it is based on the extent of damage and the perception that the public had the earthquake.

An earthquake is a more or less violent shaking of the ground which may have three origins: rupture of a fault or fault segment (tectonic earthquake); intrusion and degassing of magma (volcanic earthquakes); explosion collapse of a cavity (earthquakes occurring naturally or due to human activity). In practice we classify the earthquakes into three categories according to the phenomena that produced them.

Earthquakes Tectonic is by far the most frequent and devastating. Much of the tectonic earthquakes occur at boundaries of the plates, where there is a shift between two rocky areas. This shift, located on one or more vulnerabilities, is blocked during inter-seismic periods (between earthquakes), and the energy accumulated by the elastic deformation of rocks. This energy shift and are suddenly released in earthquakes. In areas of seduction, earthquakes represent half the number of those who are destroying the earth and dissipate 75% of seismic energy on the planet. This is the only place where there are deep earthquakes (300 to 645 km). At mid-ocean ridges, earthquakes have foci superficial (0 to 10 km), and correspond to 5% of the total seismic energy. Similarly, the level of large faults slip, place of earthquakes with foci of intermediate depth (0 to 20 km on average) which correspond to 15% of energy. The release of stored energy does not usually happen in a single shock, and may occur several adjustments before returning to a stable configuration. Thus, there are aftershocks following the main shock of an earthquake with magnitude decreasing, over a period ranging from several minutes to more than one year. These aftershocks are sometimes more devastating than the main shock, because they can bring down the buildings that had been ripped into, as rescuers were at work. It can also be an even more powerful rejoinder that the main shock regardless of its magnitude. For example, an earthquake of 9.0 can be followed by a response of ...