Coastal Systems and Landscapes: Coastal landscape development Flashcards
How is a bay formed?
- Bands of hard and soft rock are eroded
- Soft rock erodes faster than hard rock
How are tombolos formed?
- Spit is formed
- Longshore drift drags sand towards the island
- Sand connects to offshore island
How are salt marshes formed?
- Spit is formed
- Silt and mud is deposited in sheltered estuary
How are spits formed?
- Longshore drift transports material along the coast
- Material is deposited due to reduction of energy where the sea meets the river
- Hook develops due to change in wind direction
How are wave-cut platforms formed?
- Bottom of cliff is eroded by high tide
- Wave-cut notch forms
- Cliff collapses as top is unsupported
- Backwash removes cliff material from the beach
- Wave-cut platform forms
What is a raised beach?
Area of sand that is found high above the current beach
What is a dalmatian coast?
- Longitudinal coastlines that undergo submergence
- Flooded by sea level rise, leaving islands parallel to the coastline
What is a fjord?
- Glaciated U-shaped valley filled by rising sea water level
- Shallow at mouth, deep further inland
What is a ria?
- A drowned river valley
- Almost always estuaries
- WIde and deep at mouth, narrow and shallow further inland
What is an emergence coastline?
Coastline that has emerged from the water
What is a submergence coastline?
Coastline that has submerged below the water
What are the two examples of emergence coastlines?
- Raised beaches
- Marine platforms
What are the three examples of submergent coastlines?
- Ria
- Fjord
- Dalmation coastline
What are the 3 main causes of isostatic sea level change?
- Uplift or depression of the earths crust due to accumulation or melting ice sheets
- Subsidence of land
- Tectionic processes
What is the main cause of eustatic sea level change?
Tectonic uplift
How does tectonic uplift cause eustatic sea level change?
Increases the volume of water.
What is isostatic sea level change?
Sea level change on a local level due to vertical movements of the land relative to the sea.
What is eustatic sea level change?
Sea level change on a global level due to a change in the volume of the water in the sea or by a change in the shape of the oceans basins.
What is tidal range?
Difference between high and low tide.
What is a neap tide?
Tide just after the first or third quarters of the moon, where there is the least difference between high and low water.
What is a spring tide?
Tide after a new or full moon, where there is the greatest difference between the high and low water
What are rip currents?
Strong currents moving away from the shoreline.
What are storm surges?
Occasions where meteorological conditions produce high winds and then higher wave levels than those at high tide.
Define coastal sediment budget:
The balance between sediment being added to and removed from the coastal system
