- Morphology: The study of the shape of land
- Determined by geology type and structure and erosion caused by waves, saltwater and tides
- Lithology: The study of rocks, part of geology (study of earth)
- Rocks From Hardest To Softest: Granite, sandstone, limestone, boulder clay and sand dunes.
Types
of Coast:
- Large-scale geological structures which determine if a coast is discordant or concordant.
- Concordant: same geology along the coast, therefore, the coast is straighter.
- Discordant: Different geological structures or rock types, therefore, the coast has headlands and bays
Discordant
Coastlines:
- Alternating harder and softer rock along the coast. South-Western Ireland is an example.
- Differential erosion means softer rock is eroding faster by waves and form bays (erosion is occurring at a different rate).
- Resistant Geology erodes more slowly and sticks out as headlands
Concordant
Coastlines:
- Two main types: Dalmatian type coasts and Haff Type coasts.
- The Dalmatian Coast is in Croatia and it has Limestone all alone the coast, similar erosion along the coastline, more strength. Landscapes: Islands have formed where rock has folded, forming long mountains where the sea level has risen to flood the valley. Adriatic Sea is one example of this.
- Concordant coastline, same geology across the land, sand and rock along the coast, coastal landscapes are lagoons, salt marshes, spits, sand dunes.
Small
Scale Structures:
- On a small scale, morphology and erosion rates are affected by Geology type and structure
- Joints/Jointing: Small vertical cracks in rocks, for example, Flamborough head, Holderness Coast.
- Strata: Horizontal layers of rock
- Faults/Faulting: Large cracks throughout earth due to tectonic movement, caves can form here due to weaknesses in the rocks where the faults can cross over.
- Folding and Dip: Rocks folded due to tectonic forces which creates varied dip and weaknesses. No dip = flat and steep dip = vertical.
Cliff
Profiles:
- They show indentations and protrusions as well as small features such as caves, blowholes and geos.
- Wave attacks & Subaerial processes
- Geology which is the most important. (the type and structure of the rock)
- Horizontal Dip: Vertical or near vertical profiles with reflecting strata that are easily eroded.
- Seaward Dip: High angle, sloping with one rock layer facing the sea, vulnerable to the rocks sliding down the dip slopes. Low Angle: Exceeding 90 producing areas of overhanging rocks, vulnerable to rock fall
- Landward Dip: Steep profiles of 70 and 80 producing a stable cliff with reduced rock falls.
Summary:
- Coastal Landscapes vary due to rock types and structures.
- Soft rock erodes more
- Discordant coasts have more headlands and bays
- Rocks with more faults, joints and cracks have a weaker structure and erode more.
- Cliff profiles vary due to rock structures
- Micro-features like caves form due to small structures changes like faults.