The process of a mass of material moving downslope along a curved surface is called mass wasting.

Here's a breakdown of why:

* Mass wasting is a general term used in geology to describe the movement of rock, soil, and other debris downslope due to gravity.

* Curved surface implies that the movement is not simply a straight slide, but involves a more complex path.

Therefore, mass wasting is the most accurate and comprehensive term to describe this process.