What is a hallmark feature of normal faults?

Normal faults are characterized by the movement of the hanging wall down relative to the footwall. This type of faulting typically occurs in extensional tectonic settings where the Earth's crust is being pulled apart. As the crust stretches, it causes fractures which allow the hanging wall to drop downward, creating a distinct geologic feature.

This characteristic of normal faults can be easily visualized in relation to the structure of the fault. The term "hanging wall" refers to the block of rock that is above the fault plane, while the "footwall" is the block below it. When extension occurs, the hanging wall moves downward, which is a telling feature of normal faulting.

Understanding normal faults in the context of tectonic activity is crucial, as they are often associated with rift valleys and can lead to significant geological formations. The movement of the hanging wall downwards is a critical part of recognizing and classifying fault types in geology.