INDIAN GEOGRAPHY

Detailed explanation-1: -If there is no movement of one side relative to the other, and if there are many other fractures with the same orientation, then the fractures are called joints. Joints with a common orientation make up a joint set (Figure 13.19).

Detailed explanation-2: -Fractures are simply cracks in the crust where there is no movement. Faults are classified according to the direction of relative movement along the fault. The terms hanging wall and foot wall refer to the relative position of the plates after movement.

Detailed explanation-3: -A joint is a type of extension fracture formed by movement of the rock in a direction perpendicular to the plane of fracture. Joints form in solid rock that is stretched and its brittle strength (the point at which it breaks) is exceeded. When this happens, the rock fractures.

Detailed explanation-4: -Joints are more or less regular groups of fractures paralleled by little or no movement or orientation of rock components. Fractures paralleled by movement are, of course, faults, and those paralleled by considerable or pervasive orientation of minerals or other rock components are cleavage of one sort or another.