GEOLOGY

Detailed explanation-1: -The correct answer is-(1) velocity of the river decreases. When the velocity (the speed) of the river decreases, be it at the entry of a lake, sea, ocean, or meandering, passing through a valley with very little change in altitude, the sediment starts to get deposited.

Detailed explanation-2: -As the flow velocity increases, only larger and larger particles will be deposited. Particles between these two curves (either moving too slow or being too small to be eroded or deposited) will be transported in the stream.

Detailed explanation-3: -When there is a decrease in velocity, especially in pools and deep areas of a stream/river, sediments will eventually settle and can be seen as deposits of fine material or by the formation of sand bars on the river or stream bed.

Detailed explanation-4: -Increased flow will increase the stress on the bed, making it more likely for water flow to initiate sediment transport. The higher velocity also increases erosion rates as flow overcomes the shear stress of sediment 13.

Detailed explanation-5: -Deposition happens when a river loses energy. Deposition may take place when a river enters an area of shallow water or when the volume of water decreases-for example, after a flood or during times of drought. Deposition is common towards the end of a river’s journey, at the mouth .