Paper 2: UK geographical issues Flashcards
what is the link that will help you with this topics revision ? :) You have to memorise it of course
https://www.coolgeography.co.uk/gcsen/PL_River_Valleys.php
Abrasion definition
A form of erosion where loose sediment ‘sandpapers’ the walls and floors of a river, cliff, or glacier.
Attrition definition
rocks bang against each other chipping away to make smaller, smoother rocks
Hydraulic Action definition
The force of compressed air or water forced into cracks in a rock face will cause the rock to weaken and break apart
Solution definition
Material dissolved in water and carried in the river current
Erosion and transportation process
Backshore
the upper beach closest to the land, including any cliffs or sand dunes
Beach nourishment
(soft engineering management strategy)
The addition of sand and sediment to an eroding beach by humans. The new material will be eroded by the sea which saves the cliffs or sand dunes from erosion and recession
What are the 3 types of weathering?
Biological, chemical and physical
What is biological weathering
Rocks broken apart by vegetation and roots, or chemical reactions from animal faeces erode the rock face
Chemical weathering
The weak acid in rainwater will dissolve chemical compounds in the rock
Physical weathering / Mechanical weathering. and some examples
same thing just different names for it
The breakdown of rocks due to forces, not chemical reactions
EG physical processes such as changes in temperature, freezing and thawing, and the effects of wind, rain and waves.
Freeze thaw definition
A form of physical (sub-aerial) weathering where water freezes in the cracks of a rock, expands and enlarges the crack. This weakens the rock overtime leaving it more open to erosion.
Soft management
The use of natural materials and environmentally sustainable approaches to reduce coastal recession.
4 Examples of soft management
Beach nourishment, managed retreat, sand dune, encouragement
Hard management
The use of concrete structures to reduce or halt the recession of a coastiline
3 Hard management examples
Groynes, sea walls, rock armour
Geology
The physical structure and arrangement of a rock
mass movement definition
where there is a large downhill movement of material usually from a cliff-face. Here, the rock is often weak due to erosion and the movement is caused by gravity.
concordant coastiline
a coastiline where bands of alternate geology run parallel to the coast.
Corrasion
A form of mechanical (physical) erosion / weathering where waves pick up beach material (e.g. pebbles) and hurl them at the base of a cliff.
Discordant coast.
A coastline where bands of alternate geology run perpendicular to the shore.
What are the three rock types (geology)
Sedimentary rock, igneous rock and metamorphic rock
What is sedimentary rock?
Rock that has formed as sediment and rocks become compressed and cemented together over thousands of years.
Igneous rock
Rock that has formed from volcanic activity, often cooled magma on the Earth’s surface,
Metamorphic rock
Rock formed under intense pressure and heat, often close to tectonic plate boundaries.
What is a spit?
A long depositional landform, formed from sand and shingle
What are the 4 ways that a river transports the materials within it?
Suspension, saltation, traction and solution
Traction?
Large rocks and boulders are rolled along the bed of the river or sea.
Suspension
Small rocks that are light enough to float are carried in the water, rather than along the bed.
Saltation?
A form of transportation where smaller sediment bounces to reduce marine erosion at the base of cliffs.
what is a Groyne
A form of hard engineering. Low lying concrete or wooden walls, constructed perpendicular to the seafront and run out to sea. They encourage the trapping of sediment to reduce erosion caused by longshore drift or by winds
What is a sea wall?
A hard-management coastal defence, where a concrete wall is built parallel to the seafront, to redirect the energy of waves away from sensitive cliffs or the edge of a coastal town.
What are highlands?
Areas of land that are high elevation and tends to have a larger relief.
Lowlands?
An area of land that has a small relief, so tends to be flat and at a low elevation.
Longshore drift?
The transportation of sediment along a beach. Longshore drift is determined by the direction of the prevailing wind.
What is the fetch?
The length of water over which the wind has travelled.
What is relief?
The difference in height of land for a particular region. A large relief means a region has a large difference between the lowest and highest points.
What is a sand dune?
A depositional landform, where sand and sediment build up around driftwood and accumulate over time.
Erosion definition
The wearing away of rock
Deposition defnition
When material is deposited or left behind.
eg when a river loses its energy and is unable to carry its load any further, or waves move sand onto a beach but lack the energy to carry it away.)
sediment definition
Small fragments of rock and soil that form layers.
swash definition
The water flowing towards a beach when a wave breaks.
destructive wave definition
Waves which remove material from the beach. The swash is weaker than the backwash.
Constructive wave definition
Waves which help build up material on the beach. They tend to have a low frequency and strong swash. (stronger than the backwash)
backwash
The movement of water down the beach.
Impermeable (rock)
A rock that does not allow water to pass through it.
permeable (rock)
A rock that allows water to pass through it
what is a storm hydrograph?
It is a graph to show the variation of river discharge over a short period of time (days).
load
The particles of rock carried by a river.
There are some different types of mass movement. Name some (4)
Rockfall (scree is evidence of rockfall)
Soil creep
Landslides and slumping
What are the three processes which shape rivers and cause change in their characteristics?
Erosion
Transportation
Deposition
what is the (river) bank?
The side of a river channel. (river channel literally just means river / stream)
what is a (river) bed?
The bottom of a river. (The river flows over it.)
What is a drainage basin ?
1) the official definition
2) my own definition for understanding
A drainage basin is…
1) The area drained by a river and its tributaries
2) Basically the entire river from start to finish, with it’s different features long the way eg the source, the tributaries…. there is a drainage basin diagram is the diagram with the source, confluence etc labelled.
What is the source?
The upland area where the river begins
What is a confluence?
The point at which two rivers join
What is the mouth?
Where the river flows into the sea, or sometimes a lake
What is a tributary?
A river which joins a larger river
Watershed?
The boundary dividing one drainage basin from another - a ridge of high land. A river’s catchment area.
What is an estuary?
An estuary is where the river meets the sea. The river here is tidal
What is the difference between a mouth and an estuary?
An estuary is the zone of mixing between the river and the sea whereas the mouth is defined as the location at which the river ends and the sea body begins.
what is ‘dissolved’ (aka what is the stuff carried by solution)
Dissolved chemicals are carried along in solution, invisible to the eye.
what is carried in the river by suspension? (this is known as ‘float’)
Tiny particles of sediment are carried in suspension in hte river’s curent.
What is carried in the river by saltation? (called skip or bounce)
Smaller stones or pebbles are picked up and then dropped again. This results in a ‘skipping’ motion called saltation.
What is rolled or dragged in the river (by traction)
Large stones are dragged along by traction
Do you need most energy for traction , saltation, solution, or suspension
Clearly, you need more energy/ faster flow for traction in order to move the large load/sediment
what is the long profile?
A long profile is a line representing the river from its source to its mouth
what is a cross profile?
simply shows us a cross-section of the river
difference between long and cross profile
The cross profile simply shows us a cross-section of the river, while the long profile shows us how the gradient changes over the course of the river.
What is bradshaw’s model?
heoretical model that shows how a river’s characteristics change as it goes downstream.
gradient definition (river terms)
The slope of the river valley (steeep, flat)
Load definition (river terms)
The material the river is transporting
width definition (river terms)
the length across the river channel
depth definition (river terms)
how deep the river channel is
velocity (river terms) definition
The speed of a river, measure in metres per second
Discharge definition (river terms)
The volume of water flowing in a river, measured in chibic metres per second