Tag: geography

River system having the largest drainage system in the world is Amazon river

The flow velocity, or speed of flow, can influence the shape and rate of erosion of a river system. The cross-sectional shape of a river dictates how much friction will impact the flow of water within a river. Finally, the sediment load, or the amount of rocks and soil in the river, impacts its flow velocity and shape.

The last past of the river when it reaches the end of its journey, it is called an old river or the old stage. The end of the river is called the mouth. At the mouth, there is often a river delta, a large, silty area where the river splits into many different slow-flowing channels that have muddy banks. At this stage deposition is the only work of the river.

Erosion is the action of surface processes that remove soil, rock, or dissolved material from one location on the Earth's crust, and then transport it away to another location. The particulate breakdown of rock or soil into clastic sediment is referred to as physical or mechanical erosion; this contrasts with chemical erosion, where soil or rock material is removed from an area by its dissolving into a solvent, followed by the flow away of that solution. Eroded sediment or solutes may be transported just a few millimeters, or for thousands of kilometers.

Natural rates of erosion are controlled by the action of geomorphic drivers, such as rainfall or bedrock wear in rivers or coastal erosion by the sea and waves or glacial plucking, abrasion, and scour; areal flooding; wind abrasion; groundwater processes; and mass movement processes in steep landscapes like landslides and debris flows.

The place of origin of a river is called Source of the river. The beginning of a river, when it flows quickly with lots of energy, is called the young stage or the source. This age is also called as upper age. The river here is smaller and usually has a rapid, tumbling flow that cuts a narrow channel through rocky hills or mountains.

The V-shaped valley is formed in the youthful stage of the fluvial cycle of erosion and in the initial stage of valley development. It is deep and steep-sided river valley, both the valley sides meet together at the valley floor and thus water always touches the valley sides. The V-shaped valley is the result of the accelerated rate of downcutting.