Rivers Flashcards

Question

Where is lateral erosion dominant?

Answer 1

Middle and lower course.

Answer 2

Diagram that shows the change in gradient with distance.

Answer 3

Diagram that shows the shape of the valley from one side to another.

Answer 4

Smoother channel, so less of the river's energy is lost to friction.

Answer 5

Projecting ridges that extend alternately from opposite sides of a V shaped valley. The river winds around its course as it erodes the soft rock a lot faster than the hard rock.

Answer 6

Upper course landforms that form when hard rock is on top of soft rock. Hydraulic action and abrasion wear away the soft rock. Erosional processes continue to make a height difference, resulting in the formation of a step. A plunge pool is formed and an overhang now exists. The hard rock collapses due to gravity as the soft rock has been eroded away by hydraulic action from the splash back. The waterfall retreats through the valley. A steep-sided valley remains from where the waterfall once was, this is known as a gorge.

Answer 7

Erosion on the outside (as water flows faster), deposition on the inside (as water flows slower).

Answer 8

If there is a weakness on one side of the river. Erosion is fast on the outside of river bends, due to the smooth river bed and lack of friction, which causes the river to bend in a direction. This forms a river cliff. Deposition happens on the inside of river bends, due to the rough river bed and increased friction, which causes the river to become further away from its original course. This forms a slip-off slope. Overtime, the horseshoe shape will become tighter due to erosion down the middle, and the two ends will meet. The loop will be cut-off from the main channel. This cut-off loop is known as an oxbow lake.

Answer 9

A wide, flat area of land, partially due to meander migration where rivers erode laterally into the valley. This land is higher and more fertile after floods because of deposited material.

Answer 10

Bank of land either side of the river which can be manmade or naturally made. When a river floods, the water has friction with the land and sediment is deposited. Heavy sediment is deposited closer to the river and smaller sediment is deposited further away from the river. This is known as graded deposition. When these are made naturally, the risk of flooding is increased as the sediment becomes thicker on the river base, reducing the channel capacity.

Answer 11

Where the mouth of a river meets the sea. A very wide section of the river where the sea and river meet. Dominaed by tidal processes which create mudflats and deltas. The abundance of sediment and slow water flow results in massive amounts of deposition.

Answer 12

A river is at risk of flooding if the volume of water in the river channel is larger than the capacity of the river channel.

Answer 13

When the ground is saturated with water and can no longer allow water to infiltrate which results in surface runoff.

Answer 14

A graph which shows how a river's discharge changes in response to a rainfall event.

Answer 15

The River Valency flooded which caused two million tonnes of water to surge through the village.

Answer 16

Development of flood management strategies brought the community together.

Answer 17

Some people feel as if the village is no longer the same after the flood.

Answer 18

Rebuilding of Boscastle increased investment into the area which has increased the number of tourists.

Answer 19

It cost £5m to implement the flood management scheme which is a lot for a small village.

Answer 20

Risk of flooding has gone from 1 in 10 years to 1 in 75 years.

Answer 21

Trees were removed from along the riverside which makes the area less attractive.

Rivers Flashcards

(45 cards)