Sediments deposited by a river, from fine grains such as silt to coarser sands and gravels.

Sediments deposited by a river, from fine grains such as silt to coarser sands and gravels.

• A. River Cliff
• B. Alluvium
• C. Mouth
• D. Plunge Pool

Answer: (B)

Alluvium refers to the sediments laid down by a river as its flow loses energy, building up deposits along the floodplain and within the valley. These deposits can range from fine silt to coarser sand and gravel, depending on how energetic the flow is and where the sediment settles. When a river overflows its banks during floods, it drops these materials and creates fertile soils in the valley. This distinguishes it from other features: a river cliff is an eroded, steep bank rather than a depositional layer; the river mouth is where the river meets a sea or lake and can form deltas through deposition, but the broad term for the sediments described is alluvium; a plunge pool is carved by the downward force of falling water at a waterfall, not a depositional plain.

Alluvium refers to the sediments laid down by a river as its flow loses energy, building up deposits along the floodplain and within the valley. These deposits can range from fine silt to coarser sand and gravel, depending on how energetic the flow is and where the sediment settles. When a river overflows its banks during floods, it drops these materials and creates fertile soils in the valley. This distinguishes it from other features: a river cliff is an eroded, steep bank rather than a depositional layer; the river mouth is where the river meets a sea or lake and can form deltas through deposition, but the broad term for the sediments described is alluvium; a plunge pool is carved by the downward force of falling water at a waterfall, not a depositional plain.