Gelogical Structure

Question 1

Concordant vs discordant coastlines

Answer 1

Shape of a coastline is continually changing due to the surrounding geology which contributes to its morphology
Coasts = dis + con

Question 2

Concordant coastlines

Answer 2

Alternating bands of hard + soft rock parallel to the coast

Question 3

Discordant coastlines

Answer 3

Discordant coastlines have alternating bands of hard + soft rock at 90 degrees to the coast
Erosional landforms are more common on discordant coastlines because erosion happens at different rates along their length

Question 4

E.g. = discordant coast

Answer 4

Forest the coastline consists of Portland limestone + Greensands
Greensand’s is less resistant to erosional processes + so retreats at a faster rate than Portland limestone
Resulted in the creation of a bay + headland

Question 5

Coastal morphology

Answer 5

Shape of a coastline is continually changing because of the surrounding geology which contributes to its morphology

Question 6

Pacific coasts

Answer 6

Concordant coastlines also referred to as Pacific coasts lead to the formation = Dalmatian coasts
Dalmatian coasts = made up of offshore islands + coastal inlets running parallel to the coastline
E.g. Lulworth Cove located on the s-w Dorest coastline. Here the more resistant rock (e.g. limestone) acts as a barrier to protect the less resistant rock

Question 7

Atlantic coasts

Answer 7

Headlands + bays often form on discordant coastlines (Atlantic coasts)
As the faster eroding less-resistant rock retreats (clay at Swanage Bay) this leaves behind the more-resistant rock as headlands

Question 8

Bays + headlands

Answer 8

On discordant coastlines the retreating less resistant rock + the exposed resistant rock cause a change in the shape of the coastline. Leads to wave ref reaction
Change in the way in which waves approach the coastline can cause an increase in the rate of erosion on the headlands
Leads to the formation of headland features = caves, arches, stacks, stumps

Question 9

Geological structure

Answer 9

Shape of a coastline is continually changing because of the surrounding geology which contributes to its morphology

Question 10

Joints + faults

Answer 10

Geological structure of rocks (formation of joints + angle of dip, faulting + folding) is caused by the deformation + stress placed on them from tectonic processes.
Rocks with the presence of more joints + faults like sedimentary rocks are more susceptible to the processes of erosion + weathering. Because these processes exert forces on the weaknesses found in the layers of rocks

Question 11

Dip

Answer 11

Angle the rock layer forms with the horizontal bedding plane is referred = dip. Rocks can dip either towards land OR sea
Bedding planes that dip towards the sea create a gentler cliff profile. But these cliffs are vulnerable to mass movement like rockfalls
Bedding planes that dip towards land tend to create a steeper cliff profile. But these cliffs are more vulnerable to erosional process = hydraulic action + abrasion