Plate tectonics

To learn more about the current structure of the Earth's upper and explain the reasons for the earthquake happened, by the theory of plate tectonics (Plate tectonics) to illustrate. Plate tectonics theory of the twentieth century the Earth are the most significant scientific achievements, all the evolution of the Earth crust, can be explain by the theory of operation of the plate. 
The doctrine that the earth surface range of 100 kilometers of lithosphere, on behalf of plate itself, and 100-200 km for the asthenosphere, are more prone to deformation of the part of the lithosphere "floats" in the mobile asthenosphere. 


Plate is divided into two types: ocean plate and continental plates, the ocean plate by the high density of silicon magnesian rocks tend to base, and the lighter continental plate from aluminum silicate rocks acidic bias. 


The Earth's interior as a result of the role of thermal convection, magma rising is that the surface plate rifting, resulting in separation of plate boundaries (divergent boundaries), mid-ocean ridges are represented in the region have many shallow, normal faults (RIFTING role ) type of small earthquakes. In the mid-ocean ridge magma from deep plus come in, are generated by ocean plate, are in the shallow basalt, deep, compared with gabbro. 

Ocean plate to two centimeters per year rate of outward expansion (known as seafloor spreading theory), until the edge of continental plates meet, due to heavier ocean plate would subduction under the continental plates, resulting in polymerization of plate boundaries (convergent boundaries). Ocean plate in the extrusion process, will promote the continental plates move, have a "continental drift", the current distribution of the world's five continents, are from a large piece of the former "Pangu" Zhang open to the mainland. Polymerization as a result of two different plate boundaries, the nature of the plate collision, and continuously in extrusion, and constantly in the accumulation of deformation energy, until more than be able to endure the extent of the rock, then accumulation of deformation energy released in an instant, the earthquake happened. This enormous collision forces so that polymerization of plate boundaries, many of the deeply shallow, thrust fault (compression) type of a major earthquake. Ocean plate along the subduction zone, subduction under the continental plate into approximately 700 kilometers under the will and the assimilation of the surrounding material, so most of the earthquake can also be 700 kilometers arrival. Taiwan earthquake hit near the arrival of up to 300 kilometers, on behalf of the role of the subduction of younger, smaller scale. 

Apart from the edge of the separation plate (mid-ocean ridges) and polymer plate margins (continental margin), there are not a third plate of Health has not quenched the edge of sport, known as the transformation fault (transform fault), around the mid-ocean ridges in the vicinity of the seabed terrain, we can see a very long cracks, that is, transformation fault. Transformation does not fault the accumulated too many earthquakes. 

Because of the various convection direction and speed of the exercise is not consistent, they are driven by plate movement is also inconsistent, making the adjacent plates separated from each other will happen, each side of the collisions or rub each other and so on. And because the constantly shifting plates, so constant in the accumulation and release of energy, earthquakes happen continuously cycle was known as the elastic rebound theory (Elastic Rebound Theory). 


Perhaps from the above described plate theory may be that closely related to plate movement and earthquakes, from all over the world the location of an earthquake can be outlined plate morphology. Seven plates are from the global composition of the ocean plates have also have continental plates, between relying on a number of small plates miscellaneous. 


More rigid internal plate, so the earthquake happened in the interaction between plate and plate, the plate boundaries, that is. Taiwan earthquake, that is, in the Philippine Sea plate (Ocean plate) and the Eurasian plate (continental plates) under the interaction.