The earth is made up of two layers, the lithosphere and ethno-sphere. Lithosphere is the outermost part of the earth which is solid rigid and cold while the ethno-sphere is usually molten. Lithosphere comprises of the crust and the upper mantle which is divided in to eight main parts known as the plates (Williams, 2004 pp.66). The movement of the tectonic plates is known to cause earth quake. This mainly occurs along the plate boundaries where faults are found. When the plates slide smoothly past one another there is usually no problem but when the movement along the fault is hindered, then the earthquake occurs after enough pressure has been generated. As the main cause of earth quakes is the plate movement this paper will explain the different types of plate movements as well as how these movements cause earth quakes.
Plates move although it has been recorded that they move at a low speed (Williams, 2004 pp.70). Further studies reveal that equator fossil plants have been found at the Antarctica. The plate movements vary with the location such that some plates have been found to move faster than others. According to Williams, Plates in Pacific move at 16cmyear while those in Atlantic move between 1 and 2cmyear (2004 pp.70). Tectonic plates move in different directions and due to this they form three different types of boundaries. When plates move away from one another they form divergent boundaries (Klous, 1996 pp.34). During the movement, crust forms in between the two plates as a space is created in between them. A good example of the divergent boundaries that have formed is the Great Rift Valley in East Africa and also the East Pacific Rise. Convergent boundaries arise when the two plates movement is towards each other in a process known as subduction (Johnson, 2006 pp.61).
During the plate movement, a lot of pressure builds up until an opening develops in between the two plates. The opening in the crust between the two plates is known as a fault boundary (Williams, 2004 pp.74). In cases where plates slide past one another, the boundary that is formed is known as the transformal boundary. The continuous movement of the fault block generates pressure which provides the force necessary for the continuous movement of the plates. In California, there is one transform fault boundary known as the San Andreas. It was formed as a result of the Pacific plate movement towards the north and the continental plate movement towards the south (Williams, 2004 pp.74).
Additional faults usually result after a lot of pressure is generated along a major fault. These additional faults are usually known as thrust faults (Williams, 2004 pp.75). However, further studies reveal that the pressure that is not released through the thrust faults causes sideways faulting. The pressure that is not released by sideways faulting is usually released by earthquakes. Williams further reports that earthquakes that happened near San Francisco in 1906-1989 were as a result of slide slip transform fault movement (2004, pp.76).
The movement of the plates along the fault builds up energy which is then released as an earthquake (Gardiner, 2006, para.1).
However, this energy may accumulate for a very long time before it is eventually released. It can even take whole millennia before it is released or even some few decades. During the release of the energy, waves known as the seismic waves originate from the point where the energy was released and travel in all directions. People who are on the earths surface experience these waves during the time of the earth quake.
Plates move although it has been recorded that they move at a low speed (Williams, 2004 pp.70). Further studies reveal that equator fossil plants have been found at the Antarctica. The plate movements vary with the location such that some plates have been found to move faster than others. According to Williams, Plates in Pacific move at 16cmyear while those in Atlantic move between 1 and 2cmyear (2004 pp.70). Tectonic plates move in different directions and due to this they form three different types of boundaries. When plates move away from one another they form divergent boundaries (Klous, 1996 pp.34). During the movement, crust forms in between the two plates as a space is created in between them. A good example of the divergent boundaries that have formed is the Great Rift Valley in East Africa and also the East Pacific Rise. Convergent boundaries arise when the two plates movement is towards each other in a process known as subduction (Johnson, 2006 pp.61).
During the plate movement, a lot of pressure builds up until an opening develops in between the two plates. The opening in the crust between the two plates is known as a fault boundary (Williams, 2004 pp.74). In cases where plates slide past one another, the boundary that is formed is known as the transformal boundary. The continuous movement of the fault block generates pressure which provides the force necessary for the continuous movement of the plates. In California, there is one transform fault boundary known as the San Andreas. It was formed as a result of the Pacific plate movement towards the north and the continental plate movement towards the south (Williams, 2004 pp.74).
Additional faults usually result after a lot of pressure is generated along a major fault. These additional faults are usually known as thrust faults (Williams, 2004 pp.75). However, further studies reveal that the pressure that is not released through the thrust faults causes sideways faulting. The pressure that is not released by sideways faulting is usually released by earthquakes. Williams further reports that earthquakes that happened near San Francisco in 1906-1989 were as a result of slide slip transform fault movement (2004, pp.76).
The movement of the plates along the fault builds up energy which is then released as an earthquake (Gardiner, 2006, para.1).
However, this energy may accumulate for a very long time before it is eventually released. It can even take whole millennia before it is released or even some few decades. During the release of the energy, waves known as the seismic waves originate from the point where the energy was released and travel in all directions. People who are on the earths surface experience these waves during the time of the earth quake.
No comments:
Post a Comment