Erosion Landform ( 16. Pediment )

                                                                                                                                                      Back to Erosion Landform

• A pediment is a inclined erosional surface.

• It carved into bedrock.

• It is thinly covered with fluvial gravel.

• That developed at the foot of mountains.

• It develops running water.

• It is concave surface sloping away mountainous desert areas.

• Pediments mistaken for groups of merged alluvial fans.

• The angle of a pediment’s slope is generally from 0.5° to 7°. 

• Its form is slightly concave.

• Found at the base of hills in arid regions.

• Fullest development in arid regions.

Process 

• Lateral planation / erosion by a stream.

• Sheetwash /sheet erosion.

                    -Removal thin layers of surface.

                    -Gently sloping land, by broad continuous sheets of running water.

• Rillwash / rill erosion.

• Mountain front retreating by weathering.

Formational zones

1. An inner most zone.

            -Mountainous uplands near vertical erosion.

2. An intermediate zone /degradation zone.

          -The pediment beyond the mountain front.

3. An outer zone / aggradation zone.

           -Extends beyond the pediment.

           -It is a zone of deposition.