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Flashcards in Erosion and sea level change Deck (35)
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1

Define 'weathering'

The gradual breakdown of rock in situ or close to the ground surface in three different types; mechanical, biological or chemical.

2

Define 'mass movement'

The movement of weathered material down a slope as a result of gravity

3

Define 'rotational landslide'

The downward movement of a mass on a concave/ curved slip surface

4

Define 'translational landslide'

The downward movement of material along a fault, joint or bedding plane said to be translational when the slip surface is straight

5

Define 'block slide'

A translational slide of mass consisting and moving as a single unit of a few closely related units

6

Define 'rock fall'

Similar to a block fall on slopes of over 40 degrees when material either bounces down the slip surface or falls vertically to form scree at the foot of the slope

7

Define 'topple'

The forward rotation of a mass generally occurring around an axis

8

Define 'debris flow'

A moving mass of loose soil, mud, soil and rock made weak by saturation that travels down a slope by the influence of gravity, at least 50% of the moving material must be the size of sand particles or larger

9

Define 'debris avalanche'

When an unstable slope collapses and so the material is transported away from the slip surface and may slide over underlying rocks

10

Define 'earthflow'

A downward flow of saturated fine grain material as an intermediate stage between a creep and mudflow

11

Define 'creep'

Slow downward movement of weathered material indicated by slow but persistent tilting of trees

12

Define 'lateral spread'

Rapid movement of material as a result of liquefaction

13

Define 'carbonation'

The mixing of water with CO2 to form carbonic acid which reacts with minerals in the rocks

14

Define 'oxidation'

The reaction of a substance with oxygen e.g. iron forms iron oxide which weakens the rock

15

Define 'hydrolysis'

A chemical reaction of rock minerals with water e.g. feldspar in granite and rainwater forms clay

16

Define 'freeze-thaw weathering'

When water enters a crack or joint expands 10% when it freezes exerting pressure on the rock causing the crack to widen

17

Define 'exfoliation'

Mechanical weathering in which curved plates of rock are weathered away from the rock below to form exfoliation domes along joints in layers

18

Define 'aeoliation'

Referring to the wind

19

Define 'burrowing'

When birds e.g. puffins and animals burry into the cliff

20

Define 'roots'

Plant roots grow into cracks into the slip surface and forces them to break wider when they thicken

21

Give some factors affecting erosion rates
MM
HA
J
W
H/S R
G

Mass movement
Human activity
Jointing
Weathering
Hard/ Soft rocks
Geology

22

Give some factors affecting erosion rates
C/D
SA
WR
P
C
F

Concordant/ Discordant
Sub-aerial marine processes
Wave refraction
Permeability
Climate
Fetch

23

Give some factors that affect morphology
F
CF
ER
H/D
CP

Folds
Coastal features
Erosion rate
Haff/ Dalmation
Cliff profile

24

Give some factors that affect morphology
BP/ J
F
C/D
G

Bedding planes/ joints
Faults
Concordant/ Discordant
Geology

25

Describe salt crystallisation

The growth of sea salt crystals in cracks and pore spaces can exert a breaking force but less effective than freeze-thaw.

26

What's the difference between flows and slides?

Flows are wet and fast
Slides are dry and fast

27

Describe soilfluction

Occurs mainly in tundra areas where the ground is frozen when the top layer thaws, the under layer remains frozen so saturated land flows over the subsoil

28

Give the flowchart of how sub-aerial processes affect the coastline

Rainfall - Saturated cliff - Heavier - Gravity causes cliff to fail - Slump - Bottom of the slump is eroded - Unstable cliff - Slumps again

29

President of Kiribati bought (1) of land on one of the (2) islands to grow food, source water and take refuge there. Sea levels are rising at (3)/yr and most of the land is less than (4). Sea levels are rising due to (5)

1 - 20km squared
2 - Fijian
3 - 1.2cm
4 - 1m above sea level
5 - thermal expansion

30

How much would the sea level rise if the Alpine glaciers, Greenland and Antarctica ice sheets melt?

AG - 0.6m
G - 7.3m
A - 56.6m