2. Waterfall
Headword Retreat
Hydraulic Action and attrition Vertical Erosion
• Landform occurs when there is a sudden change in gradient
• Resistant band of rock across the top causing an overhang
• Undercutting at the foot of the erosion causes the overhang to eventually collapse. Thus
causing headword erosion. A gorge is left behind.
• This usually occurs at the top course along a rivers long profile
•
3. Pothole
• Potholes are cylindrical holes in the
river bed
• They are present were there is
turbulent, high velocity water. The
water usually has pebbles in
suspension.
• The holes are drilled by vertical
erosion through hydraulic action and
attrition
