Question

choose the correct answer from the given alternatives : (2)choose the correct pair - (a)upper course of a river - gentle slope of a land. (b) Upper course of a river - domiant work in erosion (c) lower course of a river - steep slop of a land (d) lower course of a river - domiant work in transporation​

Answer 1

Answer:

Source - the point at which the river starts.

Interlocking spurs - where the river winds between ridges.

Gorge - a deep valley caused by the wearing back of a waterfall.

Waterfall - often occur where the river crosses a band of harder rock.

V-shaped valley - produced in the upper course because the river cuts down faster than the surrounding slopes are eroded.

Meander - the river starts to erode from side to side.

River cliff - the river moves faster on the outside of the bend and cuts into the valley side. The erosion undercuts the ground causing it to collapse, leaving a cliff.

River beach - (slip-off slope) the river moves more slowly on the inside of the bend. It cannot carry the larger pebbles and these are dropped here.

Oxbow lake - during floods the river cuts through the neck of a large meander. The outside bend is left as a shallow lake.

Floodplain - the river is flowing in a very wide, flat valley. When it floods, it spreads over the floodplain.

Levée - during floods the overflowing river is slowed as it leaves its bed. Silt is deposited along the banks first. Over the years the deposits build up into high ridges.

Estuary - the open mouth of the river, where it meets the sea. ☺☺