Lateral planation or erosion by a stream Sheetwash or sheet erosion, in which broad sheets of flowing water evenly remove thin layers of surface material without channel formnation .Wilson, William E. (editor) (1998) Glossary of Hydrology, American Geological Institute  Rillwash or rill erosion : Mountain-front retreating by weathering
 Sheetwash or sheet erosion, in which broad sheets of flowing water evenly remove thin layers of surface material without incising channels .Wilson, William E. (editor) (1998) Glossary of Hydrology, American Geological Institute Mountain-front retreating by weathering Lateral planation or erosion by a stream Rillwash or rill erosion , in which flow is concentrated in numerous closely spaced minute channels. Later researchers looked to a combination of these mechanisms to explain pedimentation. In numerical models that couple granitic bedrock weathering and episodic stream transport of sediments, pediments emerge spontaneously. Pediment formation is promoted by arid conditions that hinder vegetation, reduce soil cohesion, and contribute to channel bank instability. Localized flooding on terrain with high infiltration rates also promotes pedimentation. These conditions all reduce incision rates. The models correctly predict that pediments are more common in hydrologically open basins than in hydrologically closed basins.
D
Lateral planation or erosion by a stream
R
channel formnation
incising channels
A
Mountain-front retreating by weathering Lateral planation or erosion by a stream
R
:
, in which flow is concentrated in numerous closely spaced minute channels.
R
Mountain-front retreating by weathering
Later researchers looked to a combination of these mechanisms to explain pedimentation. In numerical models that couple granitic bedrock weathering and episodic stream transport of sediments, pediments emerge spontaneously. Pediment formation is promoted by arid conditions that hinder vegetation, reduce soil cohesion, and contribute to channel bank instability. Localized flooding on terrain with high infiltration rates also promotes pedimentation. These conditions all reduce incision rates. The models correctly predict that pediments are more common in hydrologically open basins than in hydrologically closed basins.