Topic 4: The UK's Evolving Physical Landscape Flashcards
Igneous rocks
Molten magma pushing into the crust then solidifying
Sedimentary rocks
Layers of sediment squeezed together to form rock
Metamorphic rocks
Heat and pressure on sedimentary rocks
Physical weathering
Freeze-thaw weathering and scree
Biological weathering
Plants and animals burrow into the ground and the ground breaks
Chemical weathering
Limestone reacts with acid rain and breaks down
Headland
A piece of land jutting out into the sea
Bay
A broad coastal inlet often with a beach
Discordant coastline
Where the geology of the rock is perpendicular to the sea
Concordant coastline
Where the geology of the rock is parallel to the sea
Hydraulic action
Waves pressurise the rock and force the cracks to widen. Power of the waves puts pressure on the cliff
Abrasion
When material scrapes along the side of the cliff a bit like sandpaper
Solution
Where there is a chemical reaction between the rocks and the water. Chemicals in the water dissolve the rock
Attrition
Where rocks hit each other in the sea and then the rocks get smaller and smaller
Wave cut notch
Where the sea erodes the soft rock faster than the hard rock leaving the hard rock hanging over the beach
Wave cut platform
When the hard rock collapses onto the beach creating rock pools
Stack
Where the sea erodes the headland so much that a bit of it is separated
Destructive waves
Where a powerful wave has a weak swash and a strong backwash and destroys the beach
Constructive waves
Where the wave has a strong swash and a weak backwash so it deposited its material
Fetch
The distance over which the wind has blown
Permeable
Where water can go through the rock
Prevailing wind
The direction in which the wind blows most often
Long shore drift
Where material is moved along the beach in the direction of the prevailing wind
Slumping
Where the water collects on top of the impermeable rock and then when it becomes water logged the top bit slips
Soft engineering
Where coastal management techniques use natural resources and don’t affect the environment
Hard engineering
Where coastal management techniques are unattractive and don’t support the environment
Extrusive rock
Minerals and interlocking crystals are small as the rock cools quickly
Intrusive rock
Minerals and interlocking crystals are larger as the rock cools more slowly.
Shoreline management plan
A plan about how a whole stretch of coast is managed rather than just parts of it
Advance the line
Putting offshore breaks in so the sea breaks further away allowing the beach to build up
Hold the line
Where you put in coastal defences to protect the coast
Managed retreat
Where you let the coast retreat up to a certain point and then protect the coast
Spit
Where material is transported in the direction of the prevailing wind, even if the coastline changes direction
Bar
Where a spit completely closes off a bay
Beach berm
A flat area on a beach that has been formed by deposition of beach material and wave action
Spring tide
Where sea levels rise twice a month due to changes with the moon
Storm surge
When the air pressure falls the sea levels rise by 10mm for every 1 millibar in air pressure
Drainage basin
Place where the river gets its water from
Estuary
Salt water meets fresh water
Source
The start of a river
Tributary
Smaller river that joins onto the bigger river
Watershed
The edge of the drainage basin where water could go either way
Infiltration
Movement of water into the soil from the surface
Interception
Where the trees and vegetation stop the water from reaching the soil
Groundwater flow
The flow of water stored in rocks
Surface run-off
Where the water flows over the soil to the river
Long profile
A line representing the course of the river from its source
Suspension
Particles are picked up if the river has enough energy
Traction
Large stones are dragged along
Saltation
Smaller stones and pebbles are picked up and dropped again. Almost in a skipping motion
Deposition
Dropping off a load when the river doesn’t have enough energy.
Scree
Loose rock
Interlocking spurs
Where the River has vertically cut into the rock and left a bit of more resistant rock jutting out of The Valley. Bits of land interlock with each other to form a V shape
Mass movement
Where fragments of broken rock move down slope towards the river
Rapid
Such as landslides. They happen very quickly
Slow
Where rain dislodges soil particles and it is moved slightly. This happens very slowly over a long period of time but can still have great effects
Thalweg
The fastest part of the river is in the middle
Ox bow lake
The part of the river that is cut off
Helicoidal flow
Where water naturally flows in a corkscrew pattern
Floodplain
The flat part either side of the river
Alluvium
Layers of mud and silt that have settled
Levee
A buildup of mud and silt either side of the river
Mud flat
When the river crashes into the sea, the river is forced to drop all of its material
Erosion
Where rock or river bed is worn away
Delta
Once a mud flat has occurred then the river has lost its path to the sea and therefore must find a new one. This causes a delta
Antecedent rainfall
Where it has rained a lot recently and the soil is saturated