Rivers

Question 1

Source?

Answer 1

The place where a river begins.

Question 2

Course?

Answer 2

The route the river takes to the sea

Question 3

Tributary

Answer 3

A small river that joins a larger river.

Question 4

Confluence

Answer 4

The point where the tributary joins the river.

Question 5

Mouth

Answer 5

The point where the river enters the sea.

Question 6

Estuary

Answer 6

The part of the mouth that is tidal.

Question 7

Basin

Answer 7

The area of land drained by a river.

Question 8

Watershed

Answer 8

The high ground separating one river basin from another.

Question 9

Hydraulic action

Answer 9

The force of the moving water wears away the banks and bed of the river.

Question 10

Abrasion

Answer 10

Small stones carried by the river wear away at the the banks and bed of the river.

Question 11

Attrition

Answer 11

The small stones in the river are worn down and broken up as they hit off each other.

Question 12

Solution

Answer 12

Rocks and soil are dissolved by acids in the water.

Question 13

Discharge

Answer 13

The volume of water in the river, more
water means more erosion

Question 14

Gradient

Answer 14

The steeper the gradient, the faster it erodes

Question 15

Roughness

Answer 15

Uneven banks and bed causes friction resulting in a loss of energy.

Question 16

Shape of river channel

Answer 16

Bigger ‘Wetted Perimeter’ creates more friction and loss of energy.

Question 17

V shaped valleys

Answer 17

This occurs because of Vertical Erosion. The river cuts down into the river bed, making it deeper. It creates a narrow deep valley.
Mechanical weathering and mass movement create the V shape.

Question 18

Interlocking spurs

Answer 18

As the rivers flows it meets areas of hard rock. It cannot erode these so it flows around them.
• This creates a zigzag course.

Question 19

Waterfalls

Answer 19

Waterfalls are formed when rivers flow over areas of hard and soft rock.

Question 20

4 ways of transportation

Answer 20

• 1. Rolling
• 2. Bouncing
• 3. Suspension
• 4. Solution

Question 21

Rolling

Answer 21

The large stones are rolled along the bed of the river.

Question 22

Bouncing

Answer 22

The smaller pebbles are bounced along the bed of the river.

Question 23

Solution

Answer 23

Dissolved materials are carried along by the river.

Question 24

Suspension

Answer 24

Light material like sand and silt are carried along (floating) in the water.

Question 25

Wide river valley

Answer 25

In the mature stage the river moves from side to side and the valley becomes wide and flat. Weathering and Mass Movement continue to wear away at the sides of the valley.

Question 26

Meanders

Answer 26

Meanders are bends or curves along the river. They are formed by erosion and deposition. Erosion occurs on one side of the river while deposition occurs on the opposite side. This continues, making the bends sharper.

Question 27

Flood plain

Answer 27

A flood plain is the flat area of land on either side of the river. After heavy rain the river sometimes floods. The water spreads out over the land on either side of the river. When the river retreats it leaves behind a thin layer of alluvium. After many floods a thick layer of alluvium is created. This is very fertile soil.

Question 28

Ox bow lake

Answer 28

An ox-bow lake is a horseshoe shaped lake found beside a river. Ox-bow lakes are formed when continued erosion and deposition create very pronounced meanders.

Question 29

Levees

Answer 29

Levees are raised banks of deposited material found along the banks of the river. When the river floods and spreads out over the floodplain, the heaviest material is deposited close to the river. Over time and after many periods of flooding this deposited material forms levees along the banks of the river.

Question 30

Delta

Answer 30

A Delta is a triangular shaped piece of land which is formed at the mouth of the river. As the river enters the sea it drops off all the remaining material it is carrying. This material builds up to form new land. The river is forced to break up into smaller channels called distributaries.