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Earthquakes can simply be defined as a naturally induced shaking of the ground caused by the fracture and sliding of rock within the earth's crust. There are at least 6,000 earthquakes detected throughout the world each year. Many people have heard about or expe ....

Middle of Essay
.... within a rocky mass within the earth's crust. The depth and the length of faults vary tremendously. Earthquakes are caused by faults that are active. An active fault is a fault along which the two sides of the fracture move with respect to each other. An earthquake is caused by the sudden movement of the two sides of the fault. Faults are divided into three main groups, depending on how they move. There are normal faults which occur in response to pulling or tension. There are thrust faults which are caused as a result of squeezing or compression. The third group is strike-slip faults which are caused as a result of either type of stress. S ....