2b.2 Geological structure influences the development of coastal landscapes at a variety of scales. Flashcards
What is the geological structure responsible for in coastal formation?
The formation of concordant and discordant coasts.
What characterizes concordant coasts?
Rock strata or folds run parallel to the coast.
What are some examples of concordant coasts?
- Dalmatian coasts
- Pacific coasts
How are discordant coasts defined?
Rock strata or structures are aligned at an angle to the coastline.
What feature is typical of discordant coasts?
A crenellated pattern of projecting headlands and indented bays.
What geological structures influence coastal morphology?
- Dalmatian coasts
- Haff type coasts
- Headlands
- Bays
What is morphology in the context of coastal features?
The shape of landscape features influenced by geological structure.
What does the term ‘strata’ refer to?
Different layers (or beds) of rock.
What is a bedding plane?
The interface between two sedimentary strata.
What is the effect of dip on cliff profiles?
It influences the angle of inclination of rock strata in relation to the coastline.
What is the primary characteristic of joints in rocks?
Fractures in rocks created without displacement.
What role do faults play in coastal erosion?
They significantly increase the rate of erosion by creating zones of easily eroded rock.
What are folds in geological terms?
Bends in rocks produced by sedimentary rock layers being squeezed.
What is the impact of a high angle of seaward dip on cliff profiles?
Produces a sloping, low-angled profile vulnerable to rock slides.
What is a characteristic of low angle of seaward dip?
Produces a steep profile, potentially exceeding 90 degrees, creating overhanging rock.
What are micro-features in coastal geography?
Small-scale coastal features such as caves and wave-cut notches.
Fill in the blank: Concordant coasts form where geological structure is such that different rock strata or folds are aligned _______ to the coastline.
parallel
True or False: Discordant coasts have a straight coastline.
False
What is the significance of the Portland Limestone on the South Dorset Coast?
It forms a protective stratum parallel to the sea.
What geological process created the Dalmatian Coast?
The collision of African and Eurasian plates during the Alpine Orogeny.
What is a haff coastline?
Coastlines formed where deposition produces unconsolidated geological structures parallel to the coastline.
What is the result of wave refraction at headlands and bays?
Increased erosion at headlands and reduced erosion at bays.
What influences the indentation of bays in discordant coasts?
The relative resistance of rock types.
What type of geological structure is found in Bantry Bay?
Heavily jointed Carboniferous Limestone.
