Coatal Landscapes

Question 1

Constructive waves

Answer 1

-strong swash, weak backwash
-low wave height
-large wavelength
-low frequency
-depositional

Question 2

Destructive waves

Answer 2

-strong backwash, weak swash
-high wave height
-small wavelength
-high frequency
-erosional

Question 3

Caves, arches, stack and stump formation

Answer 3

1) erosion of line of weakness
2) cave
3) arch
4) roof collapses -stack
5) stack erodes/ collapses -stump

Question 4

Wave cut platform formation

Answer 4

1) erosion of line of weakness
2) wave cut notch
3) cliff is undercut by waves so roof collapses, leaving wave-cut platform
4) process repeats, cliff retreats

Question 5

Headland and bay formation

Answer 5

-band of hard rock erodes slower
-band of soft rock erodes faster

Question 6

What is longshore drift?

Answer 6

Transport of material along a stretch of coastline, with the swash in the direction of the prevailing wind and backwash 90° to sea

Question 7

How are beaches formed?

Answer 7

1) material that has been eroded from elsewhere is deposited by the sea due to a loss of energy
2) constructive waves build up the beach as they have a strong swash and weak backwash
3) sandy beaches are usually found in shallow, low energy water and pebble beaches are found where cliffs are eroded by high energy waves

Question 8

How are spits formed?

Answer 8

1) longshore drift moves material in direction of prevailing wind
2) the continues until the coastline changes direction where LSD and material hits the sea/ estuary, loosing energy and depositing material
3) a hooked end may form due to a secondary wind, forming a sheltered marsh

Question 9

How are bars formed?

Answer 9

1) longshore drift moves material in direction of prevailing wind
2) the continues until the coastline changes direction where LSD and material hits the sea/ estuary, loosing energy and depositing material
3) spit grows across mouth of the bay, cutting off the sea water and forming a lagoon

Question 10

How do sand dunes form?

Answer 10

1) obstacle (drift wood) at back of beach
2) heavy grains settle against obstacle
3) the side facing the wind starts to form a crest
4) the sand falls under its own weight
5) repeated movement of material up windward side causes dunes to migrate inland
6) dune becomes an obstacle itself, growing marram grass