Topic 4-UK Geographical Issues Flashcards
Upland Areas
Tend to be North and West of the UK
Lowland Areas
Tend to be South and East of the UK
Igneous Rocks
Formed when magma from the mantle cools down and hardens. The rock forms crystals as it cools. Igneous Rocks are usuall hard
Examples of Igneous Rocks
Basalt
Granite
Obsidian
Sedimentary Rocks
Formed when layers of sediment are compacted together until they become solid rock.
Examples of Sedimentary Rocks
.Limestone-formed from tiny shells and skeletons of dead sea creatures. Limestone is hard and resistant
.Clays and Shales-made from mud and clay minerals. Very soft and weak resistance
Metamorphic Rocks
Formed when other rocks are changed by heat and pressure. The new rocks become harder and more compact.
Examples of metamorphic rocks
Slate
Schist
Ways tectonic processes have shaped the UK
Active Volcanoes
Plate Collisions
Plate Movements
Active Volcanoes
Forced magma through Earth’s crust which cooled and formed igneous rocks
Plate Collisions
Caused rocks to be folded and uplifted forming mountain ranges
Plate Movments
345-280 million years ago Britain was in the tropics and higher sea levels meaning it was partially submerged under water
Granite
.Very resistant,forms in the uplands and has cracks which aren’t evenly spread.
.Impermeable meaning it doesn’t let water through. Creating moorlands.
Slate
Forms in layers creating weak planes of rock. Generally very hard and resistant to weathering and is impermeable
Schist
Has bigger crystals than slate and splits easily into small flakes and are impermeable
Carboniferous Limestone
.Rainwater eats away at limestone through chemical weathering.
.Most weathering happens at joints (cracks)
.Permeable meaning they allow water to pass through
Chalk
.Harder than clay
.Forms escarpments and cliffs in the lowlands
.Permeable
Clay
.Very soft and easily eroded
.Forms wide flat valleys in UK lowlands
.Impermeable so water can’t pass through
Glacial Processes involved in shaping the UK
There have been many glacial periods in the UK. Ice is powerful so it was able to erode the landscape carving out large U-shaped valleys in the uplands such as the Lake district. Glaciers also deposited lots of material as they melted resulting in England being covered in till which is an unsorted mixture of clay sand and rocks.
Physical processes involved in shaping the UK
Weathering
Erosion
Post Glacial Processes
Slope Processes
Weathering
Weathering is the breakdown of rock into smaller pieces
It can be mechanical,chemical or biological
Erosion
Wears away rock. During the glacial periods ice eroded the landscape. Rivers and Sea constantly erode the landscape
Post-Glacial river processes
Melting ice at the end of glacial periods made rivers much bigger than normal with more power to erode the landscape. The ice also left distinctive landforms when melted.
Slope Processes
Mass movements such as rockfalls,slides,slumps and soil creep
How physical processes formed the Uplands
.Llyn Idwal is a tarn. It sits in a corrie that was hollowed out during glacial times
.Freeze-Thaw weathering occurs on the steep back wall of the corrie. As the rocks are broken up there are rock fall which forms scree slopes
Dry Valleys
Found in UK lowlands. These valleys have no visible river but rather flow underground in permeable chalk. These were formed duting the glacial periods.
How humans have shaped the landscape
Agriculture
Forestry
Settlement
Agriculture
Different landscapes are best for different types of farming
Arable
Dairy
Sheep
Arable Land
Flat land with good soil used for growing crops
Dairy Land
Warm and wet areas. Are good for dairy farming and there are lots of large grassy fields
Sheep
Sheep farming takes place in harsher conditions in the uplands. Sheep farming takes lack of trees in hills. Sheep farming is also called pastoral
Forestry
Is the managment of areas of woodland. Coniferous forests have been planted for timber. These trees are often planted in a straight line. When areas are felled the landscape is left bare. In some places deciduous woodland is being replanted to return area to a more natural state
Settlement
As settlements grew they further influenced the landscape
.land was concreted for roads and buildings which affected drainage patterns
.some rivers were diverted into underground channels
.some river channels were straightened or had embankments to prevent flooding
Mechanical Weathering
Breakdown of rock without changing it’s chemical composition
Mechanical Weathering that affects coasts
Salt Weathering-Sea water enters cracks, the water evaporates and crystals form which pits pressure on the rock causing it to widen and crack
Chemical Weathering
Is the breakdown of a rock by changing the its chemical composition
A type of chemical weathering
Carbonation weathering-rainwater being slightly acidic due to CO2 reacts with rock containing calcium carbonate causing rocks to dissolve from rainwater
Biological weathering
Is the breakdown if rock by living things eg plant roots break down rocks by growing into cracks and applying pressure
Mass Movement
Is the shifting of rocks and loose material down a slope
3 types of mass movement
Slides-material shifts in a straight line
Slumps-material shifts with a rotation
Rockfalls-material breaks up and falls down slope
3 types of erosion
Hydraulic Action
Abrasion
Attrition
Hydraulic Action
Waves crashing against rock and compresses the air into cracks. This puts pressure on the rock.
Abrasion
Eroded particles in the water scrape and rub against rock,removing small pieces
Attrition
Eroded particles in the water smash into eachother and break into smaller fragments
Discordant Coastlines
Coastlines that are made up of alternating bands of hard and soft rock that are right angles to the coast
Concordant Coastlines
The alternating bands of hard and soft rock that are parallel to the coast.
Bays And Headlands on Discordant Coastlines
Are most common on discordant coastlines because bands of rocks are being eroded at different rates
How the UK climate impacts on coastal erosion and retreat
Temperature are coldest in winter and have highest frequency of storms. The strong winds create high energy,destructive waves increasing erosion of cliffs.