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. 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. 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. If you have found this site useful please support us keeping A Level Geography free by making a small, secure donation via Paypal towards to the running costs of the site. Hydrographs can be used to illustrate discharge.
These can be used to show annual discharge patters of flow in relation to climate. The long profile of a river shows changes in the height altitude of the course of a river from its source to its mouth. The balance between inputs and outputs is known as the water balance or budget. The water…. There are three main types of processes that occur in a river. These are erosion, transportation and deposition.
The characteristics of a river channel change along its long profile. Changes occur in the cross profile, wetted…. Meanders A meander is a winding curve or bend in a river. A series of meanders.
A swollen river. There are several stages involved in the creation of meanders. These are discussed below. Stage 1 In low flow conditions straight river channels have bars of sediment on their beds. View Larger Map Stage 2 Where the river swings towards the bank erosion causes undercutting. Stage 3 in the formation of a meander. Point bar. Step 5 Erosion is greatest beyond the middle of the bend in the meander.
Search for:. Coastal Landforms of Deposition. Drainage Basin Hydrological System. The floodplain is covered with water when the river overflows it banks during spring floods or periods of heavy rain. Sediment is deposited on the floodplain each time the river floods. Mud deposited on the floodplain can make the soil really good for agriculture. To be the provider of geoscience data globally Navigation Main content Bottom links.
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