Rabu, 31 Maret 2010


An earthquake is a vibration or shock that occurs on the surface of the earth. Ordinary earthquakes caused by the movement of the earth's crust (plates of the earth). The word earthquake is also used to indicate the origin of the earthquake occurrence. Our earth, although solid, always moving, and earthquakes occur when the pressure is because the movement was already too large to be arrested.

1. Volcanic earthquakes (Gunung Api); This earthquake occurred as a result of magmatic activity, which usually happens before a volcano erupts. If the higher its activity will cause an explosion that also will lead to the occurrence of earthquakes. The earthquake was only felt around the volcano.
2. Tectonic earthquake; earthquake was caused by tectonic activity, namely the shift of the blue plate tectonic plates that have the force of the very small to very large. This earthquake caused much damage or natural disasters on earth, a strong earthquake vibrations can spread to all parts of the earth. Tectonic earthquake caused by perlepasan [power] that occur because of plate tectonic plates shifting like a rubber band is pulled and released abruptly. Power generated by the pressure between the rock known as tectonic disability. The theory of plate tectonics (plate tectonics) explains that the earth consists of several layers of rock, most areas of the crust will drift and float on the layer of snow. Begerak slowly so that the layer-broken and broken to collide with each other. This is what causes the earthquake tektoni.

. Maps of their distribution patterns and rules to follow specific and narrow, which follow the pattern of meetings tectonic plates that make up the earth's crust. In the earth sciences (geology), the theoretical framework of plate tectonics is postulated to explain the phenomena of tectonic earthquake that hit almost the entire region, adjacent to the boundaries of tectonic plates meeting. Example is like a tectonic earthquake that occurred in Yogyakarta, Indonesia on Saturday, May 27, 2006 early morning, at 05:54 pm,

Type of earthquake

1. Earthquakes collision; earthquake is caused by the collision meteor or asteroid that fell to earth, an earthquake of this type are rare
2. Earthquake debris; these earthquakes usually occur in limestone areas or in areas of mining, earthquakes are rare and localized.
3. Artificial earthquake; artificial earthquake is an earthquake caused by human activities, such as dynamite blasting, nuclear or a hammer that slapped onto the surface of the earth.

The cause of earthquakes

Most earthquakes result from the release of energy generated by the pressure made by the moving plates. The longer the pressure was becoming enlarged and eventually reach the state where the pressure can not be arrested again by the edge of the plate. At that moment an earthquake is going to happen.

Earthquakes usually happen at plate boundaries plates. The most severe earthquakes usually occur on the border of the plate compressional and translational. Focus earthquakes in the most likely to occur because the material is squeezed into the lithospheric layer undergoes phase transition at a depth of more than 600 km.

Several other earthquakes can also occur due to the movement of magma inside the volcano. Such an earthquake could be symptoms of an imminent volcanic eruption. Several earthquakes (rarely but) also occur due to deposition a very large mass of water behind dams, such as the Caribbean Dam in Zambia, Africa. Some more (also rare) can also occur due to injection or akstraksi fluid from / into the earth (eg at several geothermal power plants and in the Rocky Mountain Arsenal. Finally, earthquakes can also occur from the detonation of explosives. It can create scientists to monitor nuclear weapons tests conducted secret government. Earthquakes are caused by man like this is also called induced seismicity