Meanders Flashcards
What is a meander?
Sweeping bends in a river that are formed through erosion and deposition
Describe the inside bend
Deposition
Shallower
Creates a river beach/slip off slope
Describe the outside bend
Erosion
Deeper
Creates a river cliff
(This is lateral erosion) (sideways erosion)
What happens in the outer bend
Current is faster
Water is pushed to the outer bend
This reduces friction with the bed and banks
So the river has more energy for transporting material which can erode the outside bank ( e.g. abrasion and hydrolic action to form a river cliff.
What happens at the inner bend
The river doesn’t have enough energy to carry material , this causes DEPOSITION to occur and a slip off slope forms
There is more friction in the inner bend
What does an oxbow lake start off as?
A meander where erosion and deposition takes place
What is the 2nd thing that happens to the meander?
Over time the erosion of the river cliff and the deposition at the slip off slope means the neck of the meander gets narrower
What is the 3rd thing that happens?
AKA , What happens after the meander gets narrower
After heavy rain or flooding the river may gain energy and combust through
What happens after the river combursts through?
Further deposition may cut the loop off, forming an ox bow lake
What does an ox bow lake look like
A river with a lake that looks like a C beside it