Geography, asked by nairawasim, 11 months ago

What is cross-section of a meander?​

Answers

Answered by bibekgay980
2

Meanders

Meanders occur in the middle valley and are the result of erosion AND deposition processes on a river.

In this section of the valley the river erodes laterally and migrates across the valley floor over time, widening the valley.  Within the river itself, the fastest current is found on the outside of a bend and the slowest current on the inside of the bend, this can be observed on diagram A. This is because the depth of the water on the outside of the bend is deeper, so there is less friction and hence higher velocities.

Over time, this means that erosion occurs on the outside of meander bends and deposition occurs on the inside. This process can lead to formation of one of Geography's classic landforms, Ox bow lakes.  It is claimed that nearly everyone in the UK can explain how ox bow lakes form, surely a useless bit of knowledge!

Diagram A) a cross section showing the speed or velocity of water through a meander

A cross section of a meander

Diagram B) a labelled cross section to show the key features of the meander.  Note that on the shallower inside of the bend sediment can accumulate to form a slip off slope, whereas on the deeper outside of the bend where the current is faster and erosion operates, a river cliff forms.

MEANDER CROSS SECTION 2

Ox Bow Lakes

In the diagrams below, erosion of the outside of the meander means that the neck of land becomes narrower and narrower over time.

On the inside of the bend the slow flow encourages the deposition of beaches.

After a long time the neck of land gets totally cut through by erosion processes such as hydraulic action and abrasion (watch an animation of this).

This cuts off the meander bend which is totally isolated by deposition leaving an Ox bow lake, which is a crescent shaped lake that will eventually fill with reeds and sediment over time.

Answered by as9686282
0

Explanation:

भाई देखो हम को नहीं पता इसका क्या है खुद ही अपना देख लेना ठीक है

Similar questions