Type of Fault

The type of fault is defined according to the orientation (strike), the sense of slip (rake) and the inclination (dip) of the fault plane.

Strike-Slip Fault: A fault whose relative displacement is purely horizontal; 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.

Dip-Slip Fault: A fault whose relative displacement is mostly shifted vertically;

if the overlying block moves down the dip of the fault plane, the fault is termed normal; if the rock above the fault moves up, the fault is termed reverse. A thrust fault is a reverse fault with a dip of 45 degrees or less. Oblique-slip faults have significant components of different slip styles.