What is broadly defined as the detachment and movement of soil or rock fragments?

The concept being described—detachment and movement of soil or rock fragments—is known as erosion. Erosion involves the process where soil particles are worn away from their original location and then transported by natural forces such as water, wind, or ice. This definition captures both elements: the initial detachment of particles from the ground and their subsequent movement to another location, which is a fundamental process in shaping the landscape.

Excavation refers specifically to the act of digging or removing material, typically for construction or landscaping purposes, rather than the natural movement of particles. Transport describes the process of carrying materials but does not encompass the detachment phase that is crucial in defining erosion.

Lastly, deposition involves the settling or laying down of eroded materials after they have been transported. While it is a part of the broader sediment cycle, it does not include the initial movement aspect addressed in the question. Therefore, erosion is the most accurate term for the process of detachment and movement of soil or rock fragments.