the level of erosion that occurs continuously over a long period of time, resulting in the gradual wearing down of landforms and the reshaping of the Earth's surface. This process is typically driven by natural forces such as wind, water, and ice, and can be influenced by factors such as climate, geology, and vegetation. The permanent base level of erosion is considered to be relatively stable and consistent, as it represents the long-term average rate at which erosion occurs in a given area.
