Coasts

Question 1

what is longshore drift

Answer 1

sediment moving along the coastlineis a process called longshore drift
the prevailing wind blows waves carrying sediment into the beach at an angle
the waves break on shore and move up the beach (swash) and as the water runs down as backwash. this results in a zig zag motion as sediment is transported along the coastline

Question 2

prevaling wind

Answer 2

main direaction wind blows in

Question 3

swash moves

Answer 3

in the direction of prevaling wind

Question 4

backwash moves

Answer 4

downwards to gravity

Question 5

discordant coastline

Answer 5

where bands of rock are at right angles to the coastline

Question 6

concorandt coastline

Answer 6

where bands of rock are parallel to the coastline

Question 7

chemical weathering

Answer 7

breakdown/ decomposition of rock by breaking down the chemical composition

Question 8

mechanical weathering

Answer 8

breaking rocks without changing their chemical composition

Question 9

wave cut platforms

Answer 9

• waves erode the bottom of the cliff creating a wave cut notch
• over time the notch gets bigger making the rock above it unstable and unupoourted
• eventually due to the force of gravity the rock above the notch collapses and falls onto tye base of the cliff
• finally the sea erodes the remaining rocks leaving a flat platform behind which can be seen at low tie

Question 10

headlands and bays

Answer 10

-waves crash into a discordant coastline made up of different bands of rock
- hard rock is more resistant to erosion so doesn’t erode as much as soft rock
- as soft rock is eroded the coastline retreats more rapidly leaving an uneven coastline
- eventually erosion continues until there’s a bay protected either side with headlands

Question 11

caves/ stacks/ stumps

Answer 11

-crack in the rock of a headland is eroded by the sea enlarging the crack
- overtime the cave continues to widen and deepen until it forms an arch
- rock above teh arch gets unstable as its no longer supported so collapses into the sea
- part of teh headland is now cut off from eh rest leaving a stack
- this will continued to be eroded leaving a stump

Question 12

pebble beach

Answer 12

generally steep
destructive
short distance
large pebbles

Question 13

formation of pebble beach

Answer 13

1. large fetch
2. plunging destructive waves with stronger backwash means pebbles aren’t moved up the beach
3. makes beach profile steep
4. storm beach may form when they’re wind waves hurl boulders and large pebbles to the back of the beach

Question 14

sandy beach

Answer 14

generally shallow
constructive
a long way
sandy dunes