rivers

Question 1

weathering

Answer 1

the breakdown and decay of natural processes acting on rocks, on cliffs and valley sides

Question 2

freeze thraw

Answer 2

rocks breaking up from repeated freezing and weakening

Question 3

chemical (acid rain)

Answer 3

when the rocks are near a very polluted place and acid rain occurs the droplets weaken the minerals in the rocks dissolving them

Question 4

mass movement

Answer 4

the movement o a material down a slope due to gravity

Question 5

abrasion

Answer 5

rivers glaciers or waves picking up sediments and rubbing against rocks in the bed and banks valley or cliffs

Question 6

attrition

Answer 6

particles carried by rivers or waves are worn down as they collide with each other so they become smaller and rounded

Question 7

channelisation

Answer 7

the deepening and/or straightening of a river to allow it to carry more water

Question 8

confluence

Answer 8

a point where two rivers meet

Question 9

deposition

Answer 9

sediments are dropped by the river, glacier or waves that carried them

Question 10

discharge

Answer 10

volume of water flowing in a river measured in cubic metres per second

Question 11

embankment

Answer 11

an artificial bank raised above the immediately surrounding land to redirect or prevent flooding by a river, lake or sea

Question 12

erosion

Answer 12

the wearing away and removal of material by a moving force, such as a river, a breaking wave or a glacier

Question 13

flood plain

Answer 13

the flat land in the valley floor each side of a river channel, which is sometimes flooded

Question 14

ground water

Answer 14

water stored underground in rocks and soil

Question 15

hard engineering

Answer 15

strategies using artificial structures e.g concrete to prevent river or coastal flooding

Question 16

hydraulic action

Answer 16

this results from the sheer force of moving water wearing away the river bed and banks, or waves wearing away sea cliffs

Question 17

infiltration

Answer 17

the process whereby water soaks into the soil and rock

Question 18

lateral erosion

Answer 18

erosion where a river cuts sideways into its banks

Question 19

levee

Answer 19

a raised bank of sediment along the side of a river

Question 20

long profile

Answer 20

the shape and gradient of a river bed from source to mouth

Question 21

meander

Answer 21

a bend formed in a river as it winds across the landscape

Question 22

mouth

Answer 22

the point where the river leaves its drainage basin and reaches the sea

Question 23

plunge pool

Answer 23

a hollow under a waterfall created by erosion and filled by water

Question 24

point bar

Answer 24

sediment laid down on the inside of a meander bend where the river flows slowly

Question 25

reservoir

Answer 25

a large lake usually artificial, used to store water

Question 26

rip rap

Answer 26

large boulders of resistant rock placed at the bottom of cliffs that dissipate wave energy

Question 27

river cliff

Answer 27

a steep section of river bank, caused by fast flowing water eroding the outside of a meander

Question 28

saltation

Answer 28

where sediment is transported by being bounced along a river bed or sea floor

Question 29

sediment

Answer 29

material such as mud, sand and pebbles carried and deposited by rivers or waves

Question 30

sediment load

Answer 30

the sediment particles carried by a river

Question 31

soft engineering

Answer 31

flood defences that work with natural processes to reduce the risk and impact of coastal or river flooding

Question 32

solution

Answer 32

the process where some rock minerals slowly dissolve in water, which is slightly acidic

Question 33

source

Answer 33

the starting point of a stream or river, often a spring or lake

Question 34

traction

Answer 34

the transport of sediment along a river bed or the sea floor through a rolling action

Question 35

transportation

Answer 35

the movement of sediment by rivers, glaciers or waves

Question 36

tributary

Answer 36

a stream or small river that joins a larger one

Question 37

velocity

Answer 37

the speed at which a river or glacier flows; river velocity is often measured in metres per second

Question 38

vertical erosion

Answer 38

downward erosion for example of the river bed