An example might be soil profile and weathering. Prevailing ground slopes are clues as to the texture of the soil. Steep slopes are characteristic of granular materials, while relatively flat and smoothly rounded slopes may indicate more plastic soils. The absence of surface drainage or a very simple drainage pattern often indicates pervious soil. A highly integrated drainage pattern often indicates impervious soils that are plastic and usually lose strength when wet.
Drainage patterns tend to reflect underlying rock structure.
The pattern of erosion often provides clues as to the character of the soil. For instance, the cross section or shape of a gully is controlled mainly by the cohesiveness of the soil. Each abrupt change in grade, direction, or cross section indicates a change in the soil profile or rock layers. Cohesive soils generally develop round, saucer-shaped gullies. Soft, light colors or tones generally indicate pervious, well-drained soils.