Final answer:
The mass-wasting type characterized by a crescent-shaped scarp face is called a slump, which usually gets triggered by water saturation, earth tremors, or destabilizing human activities.
Step-by-step explanation:
The type of mass-wasting that is characterized by a crescent-shaped scarp face is known as a slump. A slump occurs when a section of land mass moves down a slope, leaving behind a distinct curved feature that resembles a crescent. This type of landslide is typically triggered by factors like water saturation, earth tremors, or human activities that destabilize slopes.
Common signs of a slump involve the land mass moving on a rotational plane, where the upper part of the slope becomes the scarp face and the moved down material often accumulates at the toe, creating a bulged feature. Recognizing such features is essential for assessing landslide risks and implementing strategies to mitigate potential damage in vulnerable areas.