ASBOG Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

The term "footwall" refers to the lower side of a fault. In geological terms, when a fault occurs, it creates two sides: the hanging wall and the footwall. The footwall is the block of rock that lies beneath the fault plane and is considered the lower side.

In contrast, the hanging wall is situated above the fault plane and can be visually understood as the block you could "hang" something from, such as a lantern.

Understanding the orientation of these blocks is crucial in the study of structural geology, as it helps geologists analyze fault mechanics, the movement of tectonic plates, and the formation of various geological features. The other terms listed—strike and dip—relate to different aspects of geological structures. Strike refers to the direction of the line formed by the intersection of a rock layer or fault plane with a horizontal surface, while dip refers to the angle at which a rock layer or fault inclines relative to the horizontal plane.