Waterfalls
- The river flows over bands of less resistant (softer) and resistant (harder) rocks.
- The less resistant rock is more quickly worn away due to differential erosionErosion is the process that wears away the river bed and banks. Erosion also breaks up the rocks that are carried by the river..
- The river erodes the rocks in three main ways:
- Hydraulic action 鈥 when the sheer force of the water gets into small cracks and breaks down the rock.
- Corrasion 鈥 when the river bed and banks are eroded by the load hitting against them.
- Corrosion 鈥 when the river water dissolves minerals from the rocks and washes them away.