different types of fault movements

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Different Types of Fault Movements

Normal Dip Slip Fault

NORMAL DIP SLIP FAULT

Dip Slip refers to the movement of faults along the angle of the fault plane.

Where the crust is being pulled apart, normal dip slip occurs, in which the overlying (hanging wall) block moves down with respect to the lower (footwall) block.

Reverse Dip Slip Fault

• In a reverse fault, the block above the fault moves up relative to the block below the fault. This fault motion is caused by compressional forces and results in shortening. A reverse fault is called a thrust fault if the dip of the fault plane is small.

• thrust fault, reverse-slip fault or compressional fault

• Rocky Mountains, Himalayas

OBLIQUE STRIKE SLIP FAULT

• A fault which has a component of dip-slip and a component of strike-slip is termed an oblique-slip fault. An oblique slip occurs when there is a downward movement of the earth's surface, like that experienced with 'normal movement', while at the same time having a sideways movement.  The sideways movement would indicate that there is a Transform Boundary present and the two tectonic plates are sliding past one another. 

• Yet the downward motion along with this sideways movement would indicate that there is more happening with these tectonic plates.  Some oblique faults occur within transtensional and transpressional regimes, others occur where the direction of extension or shortening changes during the deformation but the earlier formed faults remain active.

• The hade angle is defined as the complement of the dip angle; it is the angle between the fault plane and a vertical plane that strikes parallel to the fault

Strike Slip Fault

Strike Slip Fault• Crustal blocks may also move sideways past each other,

usually along nearly-vertical faults.

• This ‘strike-slip’ movement is described as sinistral when the far side moves to the left, and dextral, when the far side moves to the right.

•  If the block opposite an observer looking across the fault moves to the right, the slip style is termed right lateral; if the block moves to the left, the motion is termed left lateral. 

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