2B.2 Geological Structure

Question 1

concordant coastlines

Answer 1

rock strata or folds run parallel to the coast.

lead to the formation of Dalmation coastlines- rise in sea levels, flooded river valleys
Haff coastlines are large bays crossed by spits, creating extensive lagoons.

Question 2

discordant coastlines

Answer 2

rock strata or structures are aligned at an angle to the coastline.

create headlands and bays, causing wave refraction
-wave energy is focused on the headland, creating erosional landforms
-energy is dissipated in bays leading to lower energy formations such as beaches

Question 3

why is vegetation important?

Answer 3

it is essential in stabilising any landforms from further change

Question 4

example of a discordant coast

Answer 4

swanage bay
-on the isle of purbeck in east dorset
-headland and bay present here, the resistant chalk forms the headline.

Question 5

example of concordant coastline

Answer 5

Dalmation coast of Croatia

Question 6

how does coastal vegetation stabilise landforms

Answer 6

roots bind the soil together, reducing erosion
-when submerged, plants provide a protective layer for the ground, so it is less easily eroded
-plants reduce the wind speed, so less wind erosion occurs

Question 7

xerophytes

Answer 7

plants that are tolerant of dry conditions

Question 8

halophytes

Answer 8

plants that are tolerant of salty conditions

Question 9

strata

Answer 9

different layers of rock and how they relate to eachother

Question 10

faulting

Answer 10

the presence of major fractures, the rock has moved from its original position

Question 11

deformation

Answer 11

rock has been deformed by tectonic activity

Question 12

describe wave activity in headlands and bays

Answer 12

as waves approach the shallower water offshore of a headland, they slow down, wave height increases
-in bays, wave crests curve to fill the bay, wave height decreases

Question 13

what does wave refraction cause?

Answer 13

it causes powerful waves to concentrate at headlands and create lower, diverging wave crests in bays, reducing erosion and energy

Question 14

what happens at a dalmation coastline?

Answer 14

the sea level rises with flooded river valleys

Question 15

what happens at a haff coastline?

Answer 15

the bays are crossed by spits, forming lagoons

Question 16

what are cliff profiles influenced by?

Answer 16

-resistance of rock to erosion
-dip of rock strata in relation to the coastline

Question 17

dip

Answer 17

angle of rock strata in relation to the horizontal
(a tectonic feature)

Question 18

horizontal dip

Answer 18

vertical profile with notches reflecting strata that is more easily eroded

Question 19

seaward dip

Answer 19

sloping angle profile, rock layer faces sea

Question 20

landward dip

Answer 20

steep profiles, stable cliff with reduced rockfalls

Question 21

define faults

Answer 21

movement of rock
major fractures in rock created by tectonic forces, with displacement of rocks either side of the fault line

Question 22

define joints

Answer 22

fractures in rocks created without displacement
-erosion can exploit this weakness

Question 23

folds

Answer 23

bends in rock
they are produced by sedimentary rock layers being squeezed by tectonic forces

Question 24

micro-features

Answer 24

small-scale coastal features such as caves and wave-cut notches which form part of a cliff profile.