The Hanging Wall Moves Downward Relative To The Footwall

In a normal fault the hanging wall moves downward relative to the footwall.

The hanging wall moves downward relative to the footwall.

Normal dip slip faults are produced by vertical compression as earth s crust lengthens. These usually occur when tectonic forces cause tension that pulls rocks apart. When the hanging wall moves up in relative to the footwall it is called a fault. Along a normal fault the hanging wall moves down relative to the footwall.

A downthrown block between two normal faults dipping towards each other is a graben. Alternatively such a fault can be called an extensional fault. A normal fault occurs when the crust is extended. An upthrown block between two normal faults dipping away from each other is a horst.

Low angle normal faults with regional tectonic significance may be designated detachment faults. They bound many of the mountain ranges of the world and many of the rift valleys found along spreading margins. Normal faults usually form where tectonic plate motions cause tension. Tension is stress that pulls rocks apart.

When the hanging wall moves down in relative to the footwall it is called a fault. Another type of fault is the thrust fault where ground on one side of the fault moves up and over adjacent ground.