The UK physical landscape Flashcards
Explain Snowdonia.
Glaciated upland area formed from rock from extinct volcanoes. It contains steep mountains, such as Snowdon and glaciated valleys.
Explain the Cheshire plain.
An area of low, flat land formed by the deposition of material eroded by glaciers, this land is very fertile and is mainly used for dairy farming.
Explain the Grampian mountains.
Part of the highlands and home to Ben Nevis and are steep, rocky and sparsely populated.
Explain the downs and the weald.
A lowland area with a wide valley situated between the parallel hills of the downs. The area is no mainly agricultural.
What does rock type depend on?
How they were formed.
What is igneous rock?
Formed when molten rock (magma) from the mantle cools down and hardens. The rock forms crystals as it cools. Igneous rocks are usually hard such as granite.
What are sedimentary rocks?
Formed when layers of sediment are compacted together until they become solid rock. There are two main types in the UK.
What is the first type of sedimentary rock?
Carboniferous limestone and chalk are formed from tiny shells and skeletons of dead sea creatures. Limestone is quite hard, but chalk is much softer.
What is the second type of sedimentary rock?
Clays and shales are made from mud and clay minerals. They are very soft.
What are metamorphic rocks?
Metamorphic rocks are formed when other rocks (igneous, sedimentary or older metamorphic rocks) are changed by heat and pressure. The new rocks are harder and more compact. For example shale becomes slate and slate can become schist with further heat and pressure.
What are the three main ways that tectonics shaped the UK landscape?
Active volcanoes, plate collisions and plate movements.
How did active volcanoes shape the UK?
Land that now makes up the UK used to be much closer to a plate boundary than it is now. Active volcanoes forced magma through the Earth’s crust which cooled to form igneous rocks such as granite.
How did plate collisions shape the UK?
Caused rocks to be folded and uplifted forming mountain ranges. Many of these areas remain as uplands such as the Scottish Highlands or the Lake District and north Wales. The igneous granite is hard and more resistant to erosion. Secondly, the intense heat and pressure caused by plate collisions formed hard metamorphic rocks in northern Scotland and northern Ireland.
How did plate movements shape the UK landscape?
Britain was in tropics and was partly underwater due to sea levels. Carboniferous limestone formed in the warm shallow seas. This can be seen in the uplands of Peak District in northern England. The youngest rocks in the UK are the chalks and clays found in southern England. They formed in shallow seas and swamps and form lowland landscapes. Softer and easily eroded.
Where are igneous and metamorphic rocks found?
North and west of UK.
Where are sedimentary rocks found?
South and east of UK.
What are the characteristics of Granite?
Very resistant and forms upland areas, lots of joints (cracks) which are not evenly spread so rock can stick out and form tors. Granite is impermeable which creates moorlands (large areas of waterlogged land and acidic soil with low-growing vegetation).
What are the characteristics of slate and schist?
Slate forms in layers creating weak planes in the rock, slate is very hard and resistant to weathering but can split easily into thin slabs. Schist has bigger crystals than slate and also splits easily into small flakes. These both form rugged, upland landscapes and are impermeable.
What are the characteristics of carboniferous limestone?
Rainwater eats away at limestone through carbonation weathering along joints which can create caverns and gorges. Limestone is permeable so it creates dry valleys and resurgent rivers (rovers that pop out at the surface when limestone is on top of impermeable rock).
What are the characteristics of chalk and clay?
Chalk is harder than clay, it forms escarpments (hills) in UK lowlands and cliffs at the coast. One side of the hill is usually steep and one side is usually more gentle. Chalk is permeable so water flows through and emerges as a spring where it meets impermeable rock. Clay is soft and easily eroded which forms wide flat valleys in UK lowlands and it is impermeable so water flows over the surface so many streams rivers and lakes.
How was the UK’s landscape influenced by ice?
Parts of UK covered in massive ice sheet, ice is very powerful so it was able to erode the landscape, carving out large U-shaped valleys in upland areas such as the lake district. Glaciers also deposited lots of material as they melted. Landscape formed by glacial meltwater and deposits extend south of the ice sheets.
What is weathering?
Breakdown of rock into smaller pieces. It can be mechanical, chemical or biological.
What is erosion?
Wears away rock.
Explain how post-glacial river processes alter the landscape?
Melting ice at the end of glacial periods made rivers much bigger with more power. Also left distinct landforms when it melted such as hanging valleys.
Explain how slope processes alter the landscape.
Mass movements such as rockfalls, slides, slumps and soil creep.
How can climate affect physical processes?
Cold climate increases likelihood of freeze-thaw weathering and a wet climate increases number of streams and rivers.
How did physical processes interact to make distinctive upland landscapes?
Ice can hollow out corries and freeze thaw weathering can occur on the steep back wall of the corrie causing the rocks to break up, causing rock falls and forming scree. Ice can erode U-shaped valleys. Impermeable rock causes streams that cause erosion.
How did physical processes interact to form distinctive lowland areas?
Dry valleys with no streams as they flow underground in the permeable chalk. They formed in glacial periods when the colder climate led to more freeze thaw weathering and glacial snow melt. Wet climate leads to flooding and can overflow the river and deposit silt causing flood plain.
How have humans changed the landscape through agriculture?
People have cleared the land of forest to make space for farming, overtime walls have been put in to mark out fields.
What are the different landscapes and what type of farming are they good for?
Arable-Flat with good soil used for arable farming (growing crops).
Dairy-Warm and wet areas are good for dairy farming. Lots of large, grassy fields.
Sheep-Sheep farming takes place in the harsher conditions in the uplands as sheep are well suited to upland landscapes as they can cope with steep slopes and cold weather. Sheep farming led to lack of trees on hills as young trees are eaten or trampled so cannot grow.
How has forestry changed the landscape?
Forestry is the management of areas of woodland and can be used for timber, recreation or conservation. Little woodland now. Coniferous (evergreen) forests have been planted for timber. The trees are often planted in straight lines as they do not have to look natural. In other areas deciduous woodland is being replanted to make the area natural.
How is settlement affecting the landscape?
Water supply needed for early settlers and easily defended. Land concreted, rivers diverted through underground channels and some river channels straightened or had embankments to prevent flood.
What is mechanical weathering?
Breakdown of rock without changing its chemical composition. There is one main type that affects coasts which is salt weathering.
What is the process of salt weathering?
Seawater gets into cracks in the rock and when the seawater evaporates, salt crystals form and as the salt crystals form they expand which puts pressure on the rock. Repeated evaporation widens the cracks and can cause it to break.
What is chemical weathering?
Breakdown of rock by changing its chemical composition. Carbonation weathering is a type of chemical weathering that happens in warm and wet conditions.
What is the process of carbonation weathering?
Seawater and rainwater have carbon dioxide dissolved in them which makes them weak carbonic acids which react with rock that contain calcium carbonate. For example carboniferous limestone, so the rocks are dissolved by the rainwater.
What is biological weathering?
Breakdown of rock by living things, for example plant roots break down rocks by growing into cracks on their surface and pushing them apart.
What is mass movement?
When material falls down a slope. Shifting of rocks and loose material down a slope and it happens when the force of gravity acting on a slope is greater than the force supporting it. This causes coasts to retreat rapidly. They are more likely to happen when the material is full of water as it acts as a lubricant and makes the material heavier.
What are the three types of mass movemnt?
Slides-Material shifts in a straight line
Slumps-Material shifts with a rotation
Rockfalls-Material breaks up and falls down a slope
How do waves wear away the coast through hydraulic action?
Waves crash against rock and compress air in the cracks which puts pressure on the rocks. Repeated compression widens the cracks and makes bits of rock break off.
How do waves wear away the coast through abrasion?
Eroded particles in the water scrape and rub against rock removing small pieces.
How do waves wear away the coast through attrition?
Eroded particles in the water smash into each other and break into smaller fragments. There edges also get rounded off as they rub together.
What are joints and faults?
Cracks and weaknesses in the rock which cause the rock to erode quicker.
Explain concordant coasts.
Alternate bands are parallel causing less erosional landforms.
Explain discordant coasts.
Bands perpendicular causing more bays and headlands as the bands of rock are eroded at different rates.
How does the UK’s climate impact the coastal erosion and retreat?
Higher temp increases salt weathering as water evaporates quicker. Storms create destructive waves which increases erosion. Heavy erosion saturates soil and can cause mass movement. The prevailing (most common) winds can bring storms.
Explain destructive waves.
Waves that carry out erosional processes, they are high frequency, high and steep. There backwash is more powerful than their swash so material is removed. Storms increase erosional power which increases rates of retreat.
How do waves erode cliffs to form wave cut platforms?
Waves cause the most erosion at the foot of the cliff which forms a wave-cut notch which largens. The rock above becomes unstable and collapses and the material washes away. Repeated collapsing causes the cliff to retreat.
How are headlands and bays formed along discordant coastlines?
Hard rocks have more resistance compared to soft rocks. Headlands and bays form where there are alternating bands of hard and soft rock. The soft rock erodes and causes a bay whereas the hard rock sticks out forming a headland.
How are headlands eroded to form caves, arches and stacks?
Waves crash into the headlands and enlarge the cracks through hydraulic power and abrasion. Repeated erosion causes a cave to form. The cave is deepened until it breaks through forming an arch. Erosion continues to wear away the rock supporting the arch until it collapses. This forms a stack which is an isolated rock that is seperate from the headland. For example old harry in Dorset.
How is material transported along coasts through longshore drift?
Waves follow the direction of the prevailing wind. They hit the coast at an oblique angle and the swash carries material up the beach but the backwash carries material backwards at a right angle. Overtime zig zags from.
How do constructive waves deposit material?
Deposition is when material being carried by the sea water is dropped on the coast. Waves that deposit more than they erode are constructive waves. The swash is powerful but the backwash is less powerful. This can form beaches, they are less frequent.
What are spits?
They form at sharp bends, for example a river mouth. Longshore drift transports sand and shingle past the bend and deposits it in the sea. Strong winds and waves can curve the end of the spit forming a recurved end. The sheltered area behind a spit is protected from waves so material accumulates and can form plants. Over time the protected area can form a mud flat or a salt marsh.
What are bars?
A bar is formed when a spit joins two headlands together. The bar cuts off the bay between the headlands from the sea. This means a lagoon can form behind the bar.
What are wave cut platforms shown as?
Bumpy edges along the coast.
