The river erodes laterally (to the right and left), forms big bends and finally horseshoe loops called meanders.
Meanders are formed by deposition and erosion
Oxbow lakes
The force of the water erodes and undercuts the river bank on the outside of the bend where there is most energy due to less friction.
On the inside of the bend, where the river flow is slower, material is deposited, as there is more friction.
Over time the horseshoe becomes tighter, until the ends become very close together. As the river breaks through, eg during a flood when the river has more energy, and the ends join, the loop is cut-off from the main river. The cut-off loop is called an oxbow lake.
1 of 2
Waterfalls
A waterfall forms when hard rock lies over soft rock.
The river flows over the hard rock and the softer rock erodes away, creating an overhang.
When the overhang gets too big, the whole thing collapses because of weight and gravity.
This process repeats and the waterfall will move backwards over time.
Comments
No comments have yet been made