Meanders
Explanation
The evolution of landforms by running water (rivers) is divided into three stages: youth, mature, and old. As a river leaves the steep gradients of the mountainous region (youth stage) and enters the plains (mature stage), the velocity of the water decreases, and the river's work shifts from vertical down-cutting to lateral erosion and deposition.- Levees: Incorrect. Levees are raised natural embankments found along the banks of a river. They are formed by the deposition of sediments during flooding, not by the twisting of the channel itself.
- Meanders: Correct. As the river enters the plain, the water moves more sluggishly and begins to erode the banks laterally. This continuous lateral erosion on the outer bank and deposition on the inner bank causes the river to twist and turn, forming large, loop-like bends known as meanders.
- Deltas: Incorrect. A delta is a depositional feature formed at the mouth of a river where it meets a standing body of water (such as a sea or lake), marking the end of the river's course.
- Rapids: Incorrect. Rapids are erosional features associated with the youth stage of a river. They occur where the river flows over steep gradients with alternating bands of hard and soft rock.
Key Takeaway: Meanders are sinuous bends or loops in a river's course, characteristic of the mature stage in the plains, formed through the combined processes of lateral erosion and deposition.