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Flashcards in EQ2 Deck (51)
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1

what are the erosion processes?

hydraulic action
corrosion
abrasion
attrition

2

what influences the erosion processes?

wave type
size
lithology

3

what distinctive coastal features does erosion create?

wave cut notches
wave cut platforms
cliffs
crack cave arch stack stump

4

what is sediment transportation influenced by?

angle of wave attack
tides and currents
process of longshore drift

5

which distinctive coastal landforms to transportation and deposition processes produce?

beaches
recurved and double spits
offshore bars
barrier beaches and bars
tombolos
cuspate forelands

6

what are the subaerial processes?

mass movement and weathering.

7

what are the types of weathering?

mechanical
chemical
biological

8

what are examples of mass movement?

blockfall
rotational slumping
landslides

9

what distinctive landforms does mass movement create?

rotational scars
talus scree slopes
terraced cliff profiles

10

why is weathering important?

it is important in sediment production and influences rates of erosion.

11

what does wave size depend on?

strength+duration of wind
water depth
fetch

12

what is the process of a wave breaking?

at a water depth of about half the wavelength, the internal orbital motion of water in the wave touches the sea bed. this creates friction between the wave and the sea bed slowing down the wave. as the waves approach shore, wavelength decreases and height increases, causing waves to bunch together. the crest begins to move forward faster than the trough-when it outruns the trough the wave breaks.

13

what do summer beach profiles look like?

constructive waves
berm
sloping upwards steadily
steeper

14

what do winter beach profiles look like?

destructive plunging waves
bars
troughs/runnels
less steep, more variable

15

what do storm beaches look like?

high at the back of the beach- result from high energy deposition of v coarse sediment during the most severe storms.

16

what are offshore bars formed by?

destructive wave erosion and their deposition of sand and shingle offshore.

17

what are the sediment transport processes?

traction
saltation
suspension
solution

18

what is saltation?

sediment bounces along because of the force of the water or the wind.

19

what are the 2 main ways deposition can occur?

gravity settling
flocculation

20

what is gravity settling?

occurs when the energy of transporting water becomes too low to move sediment.

21

what is flocculation?

depositional process that's important for small particles- they clump together because of chemical attraction and become large enough to sink.

22

why do spits happen at the turn of the coast?

the LSD current spreads out and loses energy, leading to deposition.

23

why do tombolos form?

wave refraction around an island, creating an area of calm water and deposition between the island and the coast.

24

what is another word for a bar?

barrier beach

25

why do hooked/recurved spits occur?

Refraction around the end of a spit curves it into a “hook”-end curved landward, into bay or inlet.

26

what is a cuspate foreland?

triangular shaped depositional feature

27

how are cuspate forelands formed?

YEET they don't know- maybe LSD from 2 directions

28

what are the sources of a sediment cell?

offshore bars
river systems
erosion of cliffs
aeolian (wind blown) sediment
weathering and mass movement (subaerial processes)

29

what are the transfer zones of a sediment cell?

(LSD and offshore currents)
beaches
parts of dunes
salt marshes
tides

30

what are 2 examples of negative feedback mechanisms in sediment cells?

1) large cliff collapse occurs. rock debris at base of cliff protects it from wave attack, slowing down erosion.
2) major erosion of sand dunes could lead to excessive deposition offshore, creating an offshore bar that reduces wave energy allowing dunes a chance to recover.