Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physical Geography > [Unit 2B: Enquiry Question 2] > Flashcards

[Unit 2B: Enquiry Question 2] Flashcards

Coastal Landscapes

1
Q

how do waves form

A

wind blows over the sea creating friction creating capillary waves. as wind continues capillary waves grow into swells formed by some water being pushed down and some water being pushed up. This creates an orbital motion within the wave. As the wave approaches the shore it will break as it can no longer gain energy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are the two types of waves

A

constructive and destructive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the key characteristics of constructive waves

A

less frequent (6-8wpm)
lower energy (weaker)
deposition > erosion
stronger swash than backwash
carry finer sediment (0.1-2mm)
usually in the summer - calmer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are the key characteristics of destructive waves

A

more frequent (13-15wpm)
higher energy (stronger)
erosion > deposition
stronger backwash than swash
carry larger sediment (1-22mm)
usually in the winter - stormier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

why might beach profiles change in the long term

A
  • if sediment supply from rivers is reduced
  • if sediment supply along coast is reduced
  • changes to climate (stormier = winter beach profiles)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

define “storm beach”

A

high energy deposition of coarse sediment during storms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

define “berms”

A

summer swell wave depostion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

define “offshore ridge”

A

destructive wave erosion that is deposited offshore

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

when does the most erosion occur

A

waves at their largest (wind speed and fetch)
waves approach coast at 90 degrees to cliff
tide is high
after heavy rainfall (permeable strata weak)
debris is removed from cliff foot

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

define “hydraulic action”

A

waves force and trap compressed air into cracks (only type of erosion that can break igneous rocks)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

define “abrasion”

A

throwing lose sediment at base of cliff

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

define “attrition”

A

rocks bounce and reduce in size (softer rocks)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

define “solution”/”corrosion”

A

weak acid in sea dissolves rock (limestone and chalk)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

how does a wavecut platform form

A

hydraulic action and abrasion erode cliff face and create a notch. the notch grows and headland can no longer support weight. it collapses forming a wavecut platform

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how does a cave, arch, stack and stump form?

A

hydraulic action erodes crack and forms a cave. hydraulic action and abrasion deepens cave and ultimately makes through the other side into arch. the arch weathers and collapses forming a stack. the stack continues to weather and erode forming a stump

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what two other landforms can form from erosion on a headland

A

geo and blowhole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the four types of transportation

A

traction
saltation
suspension
solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

define “traction”

A

rolling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

define “saltation”

A

bouncing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

define “suspension”

A

held

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

define “solution”

A

dissolved

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what did Hjulstrom’s curve show?

A

bigger sediment, more energy required to transport
smaller sediment, less energy required to transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

how does longshore drift work

A

prevailing winds drive waves in that direction. picking up sediment in same direction. it falls perpendicular to coast due to gravity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

give an example of a wavecut platform in the UK

A

Kimmeridge wavecut platform, dorset

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
give an example of a stack/stump in the UK
Old Harry Rocks, Dorset
26
give an example of an arch in the UK
Durdle Door, Dorset
27
give an example of a cave in the UK
Fingal's cave, Scotland
28
give an example of a geo in the UK
Selwick's Bay, Yorkshire
29
give an example of a blowhole in the UK
The Devil's blowhole, Yorkshire
30
define "bar"
ridge of sand, short distance in sea. destructive waves break early - throwing sediment in a heap
31
define "spit"
LD carries sediment across coastline. when gap in coastline, it travels short distance and then lands on sea bed and piles up
32
define "tombolo"
LD carries sediment across gap between island and main land
33
define "cuspate forehead"
low lying headline. opposite LDs meet forming two spits which converge.
34
define "hooked spit"
same as regular. but secondary prevailing winds create a secondary spit
35
what happens in a sediment cell when the sediment budget falls
erosion increases - positive feedback
36
what happens in a sediment cell when the sediment budged increases
deposition increases - negative feedback
37
what are examples of inputs in a sediment cell
cliff erosion eroded beaches fluvial sediment
38
what are examples of transfers in a sediment cell
longshore drift currents (prevailing) winds
39
what are examples of stores in a sediment cell
permanent: estuaries offshore bar temporary: sub-sinks (beaches etc)
40
define "erosion"
breakdown of rock due to action of some external force
41
define "weathering"
breakdown of rock by chemical, mechanical or biological agents
42
what are the 3 types of weathering
chemical mechanical biological
43
how does biological weathering break down rock
by living organisms, such as plants, bacteria and animals
44
what are three types of biological weathering
tree root weathering, rock boring, seaweed acid
45
how does tree root weathering work
seeds fall into cracks in rock roots exert force that widens crack angular fragments break away (on backshore zone on vegetated cliffs)
46
how does rock boring work
clams and molluscs live in the foreshore zone they drill into rock with their sharp shell attack soft rocks like clays and shales
47
how does seaweed acid work
kelp contains pockets of sulphuric acid cells break, sulphuric acid attacks rocks leading to chemical reactions like carbonation
48
how does chemical weathering work
chemical reactions break bonds in minerals breaking rocks
49
what are three types of chemical weathering
carbonation hydrolysis oxidation
50
how does carbonation work
attacks calcium carbonates rain mixes with CO2 in air to make weak carbonic acid acid rain mixes with calcium carbonate dissolving it
51
how does hydrolysis work
break down bonds in minerals feldspar in igneous and metamorphic rocks make them vulnerable. water mixed with CO2 can enter
52
how does oxidation work
addition of oxygen to minerals producing iron oxides (rust) makes it weaker
53
how does mechanical weathering work
rocks are hit by rain or salt water etc
54
what are three types of mechanical weathering
freeze thaw weathering salt crystal growth wetting and drying
55
how does freeze thaw weathering work
water gets in crack, freezes expands up to 9%, widens crack bigger crack = more water continues till fragments fall off porous rocks have finer fragments
56
how does salt crystal growth work
evaporation of salt water in cracks leave behind salt crystals these expand when heated, causing cracks to widen and fragment caused by destructive wave spray
57
how does wetting and drying work
during high tide, minerals expand as they are soaked during low tide, they dry and fracture repeats until rock fragments
58
what are the 6 types of mass movement
rockfall landslides slumping mudflow solifluction soil creep
59
what is rockfall mass movement
when fragments of rock come off a steep cliff. they bounce down or drop vertically.
60
what are the causes of rockfall
mechanical weathering marine erosion geological structure seismic activity
61
what is the process of rockfall
rock is weakened by a cause section of rock detaches gravity makes it fall accumulates as "talus slope or scree"
62
what is slumping mass movement
section of cliff moves down slope in a curved motion. remaining as one
63
what are the causes of slumping
weak rock / unconsolidated material high water content waves undercutting base of cliff
64
what is the process of slumping
rain infiltrates material weight of saturated material causes it to be heavy slumps downward creates a "terraced cliff profile"
65
what is mudflow mass movement
fast moving flow of water saturated soil
66
what are the causes of mudflow
heavy rainfall deforestation steep slopes
67
what is the process of mudflow
rain saturates soil soil loses cohesion soil becomes fluid gravity pulls saturated soil down the slope flow spreads out
67
what is soil creep mass movement
slowest form of mass movement occurs on gentle slopes. ripples on slope
67
what are the causes of soil creep
repeated expansion and contraction of soil due to wet - dry cycles due to gravity
68
what is the process of soil creep
soil absorbs water and expands and right angles to the slope during dry conditions it contracts vertically. moving down slope
69
what is landslides mass movement
downslope movement of rock along a linear slip plane rock maintains contact with slope as it moves
70
what are the causes of landslides
mechanical weathering heavy rainfall marine erosion geological structure (joints and bedding planes)
71
what is the process of landslides
weathering weakens rock layers along a bedding plane heavy rain lubricates slip plane, reducing friction marine erosion undercuts base, removing support gravity pulls rocks downwards
72
what is solifluction mass movement
type of flow in permafrost regions thawed upper layer of soil moves over frozen ground
73
what is the process of solifluction
in summer, top layer of permafrost thaws thawed layers becomes saturated and slides over impermeable frozen ground landscape develops lobes of flowing sediment
74
what are the factors affecting cliff instability, leading to mass movement
rock type climate structure of rock vegetation

Physical Geography (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions