GEOLOGY

Detailed explanation-1: -Faults are cracks in the earth’s crust along which there is movement. These can be massive (the boundaries between the tectonic plates themselves) or very small. If tension builds up along a fault and then is suddenly released, the result is an earthquake.

Detailed explanation-2: -Movement of rock along a fault may occur as a continuous creep or as a series of spasmodic jumps of a few metres during a few seconds. Such jumps are separated by intervals during which stress builds up until it overcomes the frictional forces along the fault plane and causes another slip.

Detailed explanation-3: -A fault is formed in the Earth’s crust as a brittle response to stress. Generally, the movement of the tectonic plates provides the stress, and rocks at the surface break in response to this. Faults have no particular length scale.

Detailed explanation-4: -It forms when rock above an inclined fracture plane moves downward, sliding along the rock on the other side of the fracture. Normal faults are often found along divergent plate boundaries, such as under the ocean where new crust is forming. Long, deep valleys can also be the result of normal faulting.

Detailed explanation-5: -There are three main types of fault which can cause earthquakes: normal, reverse (thrust) and strike-slip. Figure 1 shows the types of faults that can cause earthquakes. Figures 2 and 3 show the location of large earthquakes over the past few decades.