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Relief of the UK Highland Processes How a river’s cross profile changes downstream. (upland) areas, The relief (height of often over 600 Transportation - The movement of sediment along the Erosion - The breakdown of sediment into smaller fragments Deposition - When waves loose energy they leave behind the The long profile of a river shows the change in height of the river’s the land) of the UK metres above smaller pieces. bed from its source to its mouth. It is typically concave, decreasing in gradient downstream. can be divided into sea level; e.g. • Managing Distinctive Landscapes: The cross profile shows the shape of the river valley. uplands and the Scottish Traction - large material is rolled along the sea floor. Hydraulic Action – The force of water into cracks helps to break Highlands it up. lowlands; each have Brecon Beacons: (glaciated Middle course their own • Saltation - material is bounced along the sea Abrasion – Waves fling and against the rock. • Establish fixed point photography of key viewpoints mountains). characteristics. floor. These wear away like sandpaper. and animals Upper course • Improve sinage by renewing or replacing finger posts Lower course • Suspension - beach material is suspended and carried Attrition - Chunks of rock get knocked together and worn into to encourage people to stick to the routes. Key Lowland areas, by the waves. smaller bits • Designated footpaths and Monitoring of footpath under 200 erosion metres above • Solution - material is dissolved and carried by the Solution – Water dissolves the soluble material from the rock. • Work with local planning and housing authorities to Lowlands sea level, water. promote affordable housing schemes using local rock largely flat or • Strict control over visitors Upper Course of a River low hills; e.g. the Fens in Near the source, the river flows over a steep gradient but has limited Uplands eastern energy. England. The river erodes vertically, producing V-shaped valleys, interlocking spurs, and waterfalls. The landscape will be affected by four main factors; / vegetation/ land use and Waterfall formation: culture. Many of these areas in the UK can be considered an Area of Outstanding Natural Beauty Hydrographs 1. River flows over layers of more resistant and less resistant such as the Lake District and Dartmoor. Flood management schemes rock Hydrographs show how the discharge of a river (the volume of water that is flowing in it, measured in cumecs – cubic metres 2. Hydraulic action and abrasion causes a plunge pool in the less Soft Engineering (enhancing Hard Engineering (building control Rock Type per second) changes over time. resistant rock natural processes) structures) A ‘flashy’ hydrograph has a short lag time and a high peak discharge, caused by lots of surface runoff. 3. The more resistant rock is undercut, leaving the rock unsupported IGNEOUS: This is formed from molten rock SEDIMENTARY: Most of these types of rocks are Afforestation – plant trees in the Artificial Levees – increase the 4. The overhanging rock collapses and the waterfall retreats often linked to volcanoes. The molten rock may formed under the sea. On the sea bed they were • Peak discharge is the highest discharge. upper course to increase height of the river banks to upstream, forming a gorge. cool slowly, allowing time for minerals to form buried by newer sediment, squeezed and interception to lengthen lag time, increase capacity. • Lag time is the delay between peak rainfall and peak large crystals, which lock together. Granite and cemented together over thousands of years to and increase evapotranspiration discharge. basalt are types of igneous rock. Igneous rocks form new rock. These rocks also include the to reduce discharge. Deepening/widening the river are very hard and durable. In the UK they form fossilised remains of sea creatures. Chalk and channel – increase the channel • mountainous areas. limestone are examples of sedimentary rocks. River restoration and managed capacity. Rising limb is the increase in discharge. flooding – restoring a river and • METAMORPHIC: Existing rocks that are transformed by great heat or pressure. These changes lead to wetlands to their natural state Dam - reduces discharge by Falling limb is the decrease in discharge the existing minerals melting and forming new minerals. Marble and slate are examples of allows a river to flood there to storing water in a reservoir. metamorphic rocks. decrease discharge downstream. • Baseflow is the discharge of the river fed by Middle Course of a River Flood diversion/relief channel – groundwater flow. Physical and Human Causes of Flooding. Floodplain zoning – allow land reduces discharge by diverting a The river now flows over a more gentle gradient, but has more uses such as parks in areas that proportion of discharge away energy (more water flowing, more quickly). The river erodes Physical: Prolonged/heavy rainfall Physical: Geology are regularly flooded and restrict from a city via a flow control laterally, creating a u-shaped valley, meanders, and ox bow lakes. This causes the soil to become saturated, Impermeable rocks prevent infiltration, housing to areas that are structure on the river e.g. the stopping infiltration and causing surface runoff causing surface runoff which decrease lag time. infrequently flooded. Jubilee River (Thames). Formation of a meander and ox-bow lake: which LANDSCAPE AND PHYSICAL PROCESSES 1. The fastest flowing water 2. Further erosion causes the increase peak discharge. Paper 1 erodes the outer bank forming a two outside bends to move river ; slower water causes towards each other, Human: Deforestation Human: Urbanisation deposition on the inner bank, narrowing the neck of the Clearing trees reduces interception and Tarmac and concrete are impermeable, forming a slip off slope. meander. evapotranspiration, increasing peak discharge. preventing infiltration and causing surface Drainage Basin runoff. 3.Erosion eventually cuts 4. Deposition separates the 2015 Cumbria Flood Drainage Basin The area of land that is drained by the river and its tributaries. through the neck of the old meander loop from the meander, and the fastest flow is new main channel, forming Causes of the flood: Effects: Watershed The area of high land forming the edge of the river basin redirected. an ox-bow lake. • The storm Desmond brought record high rainfall – • In Cumbria and Lancashire more than 43,000 348mm fell in a 24hr period (this still continues in homes are suffering from power cuts. some parts). • 40 schools closed Precipitation Moisture falling from clouds as rain, snow or hail. • Steep hill slopes meant that it flowed into rivers • 2 deaths quickly. • Shops shut before Christmas Interception Vegetation prevents water from reaching the ground. • Cockermouth is a small town that lies on the • Insurance company increased staff confluence of 2 rivers (the Cocker and the Derwent) • Sewage leaked into surrounding fields Infiltration Water absorbed into the soil . • Bridges collapsed Surface runoff Water flowing quickly over the surface of the land into rivers. Lower Course of a River Responses: • More than 100 flood warnings Throughflow Water flowing more slowly through the soil to the river. Near the river’s mouth, the river flows over a very gentle gradient. • The Government mobilised a full national emergency response. This included 200 military personnel. The river is transporting a large load of sediment which it deposits. • The government’s announced the 5,000 households and businesses affected would be given council tax and Groundwater flow Water flowing very slowly through rocks deep underground. There is a wide floodplain with levees, and ox-bow lakes. An business rate relief. with is formed where the river meets the sea (e.g. at • Evacuation of local residents to higher/ safer ground. Transpiration Water lost through the leaves of plants. Middlesbrough on the River Tees). • Improved flood defences, The Environment Agency Mass Movement Wave cut platform - Erosional Sand – Depositional Landform Weathering Weathering is when rocks are broken down. There are 3 types of weathering; Waves through hydraulic action cause erosion at the foot of the cliff. This erosion of a cliff at Sand dunes are mounds of sand that are found behind sandy . To form they require a large flat beach, a good supply the base forms a wave cut notch. As the notch grows the rock above it becomes unstable and of sand, strong wind and obstacles. Mechanical (physical) – When rocks break up due to water entering the cracks eventually collapses. The collapsed material is washed away and a new notch starts to form. and freezing and thawing, making the rock weak. Repeated collapsing causes the cliff to retreat. A wave cut platform is left behind as the cliff Eg: Ynyslas sand dunes are located on the west coast of Wales. Erosion of the cliffs in retreat Aberystwyth, then transports material along the coast. Onshore 1. Rainwater seeps into joints and fractures in the rock Wind then deposits the sand into sand dunes. 2. When the water freezes its volume expands by 9% exerting pressure on the surrounding rock Longshore drift 3. With repeated freeze-thaw and angular block of the rock breaks away A form of transportation that moves sediment from one end of the coast to the other. (scree) 1. Waves approach the beach in the direction of the prevailing wind. 2. When waves break, pushes sediment diagonally up the beach. Waves 3. Gravity pulls the water and sediment straight down the beach as backwash. A wave is a movement of energy through water, not a movement of water. The size of the waves depend 4. Over time, sediment is moved along the coast. Chemical – Caused by chemical changes. Slightly acidic rainwater slowly dissolves on 3 factors; certain rock types • The FETCH (the distance the wind blows over the water) – The greater the fetch, the more Biological – Plant roots grow causing cracks in the rocks and animals burrow into Mass movement happens when the force of gravity acting on a slope powerful the waves will be. weak rocks like sand. is greater than the force supporting it. This process causes the cliff to retreat (move back). There are 4 types of mass movement; • The STRENGTH of the wind • Rockfall – fragments of rock breaking away from the cliff Formation of caves, arches, stacks and stumps by erosion face • How LONG the wind blows for • Landslide – blocks of rock sliding downhill TEST YOURSELF: • Mudflow – saturated soil and weak rock flows down a slope • The Old Constructive Waves Destructive Waves For a distinctive landscape you have studied, discuss whether the impacts of human activity are Harry Rocks • Slumping– slump of saturated soil and weak rock along a largely positive or negative (8) curved surface this forms by: • are located Swell formed from distant storms. Formed by local storms. Explain why footpaths are eroded at honeypot sites (4) 1. Rain saturates the permeable rock above the Impermeable • off Ballard Low wave height in proportion to wavelength. High wave height in proportion to wavelength. Explain the formation of a waterfall (6) rock, increasing its weight. • Point, The swash is stronger than the backwash. The backwash is stronger than the swash. Explain why rivers deposit sediment on the inside bend of a meander (4) 2. Waves or a river erode the base of the slope making it • . Sediment is deposited, building-up the beach, Sediment is eroded from the beach, forming a less Give two factors that influence which method of transportation a rivers bed load is moved by (2) unstable. • forming a steep beach profile and berms. steep beach profile and an offshore bar. For a located coastal environment in the UK, explain the processes that have created the 3. Eventually the weight of the permeable rock is greater than specific to that environment (6) 1) Hydraulic action and abrasion erodes the joints and other lines of the strength of the underlying rock and the slope collapses • Explain how climate influences the rate of erosion in river landscapes (4) weakness (cracks) in the cliff face along a curved plane; on the coast the cliff retreats inland. • Explain how reduced infiltration in an area may result in flooding (4) 2) These are enlarged to form a 4. The loose material at the base of the slope is then removed • Explain how the process of longshore drift effects the coastal landscape (6) 3) Wave refraction focuses energy on both sides of the ; caves and transported by waves or a river. • Explain the impact on the rest of the drainage basin system of cutting down a large areas of trees (6) from both sides of the headland join together to form an arch • Evaluate the costs and benefits of a dam as a flood management strategy (8) 4) Weathering (e.g. freeze-thaw) and erosion (e.g. abrasion) causes the arch • List three factors which may affect flooding in the UK (3) to collapse forming a • Describe how porous rocks will influence the shape of a hydrograph (4) 5) Further weathering and erosion forms a stump • Evaluate the effectiveness of soft engineering as a strategy for managing UK floodplains in the future 6) Eventually the stump is eroded, leaving a wave-cut platform (8) Joint > Cave > Arch > Stack > Stump • Give one reason why some people do not want money spent on river flood management. [2] What factors effect landform change? • River Flooding is a natural phenomenon. ”To what extent do you consider this statement to be correct (8) Formation of Spits by longshore drift and deposition Headland and - Erosional Landform Geology, Climate and human use are methods that will effect the rate of change in both coastal and river landforms. • Explain how a change in the hydrological cycle in an area may result in flooding (6)

• Waves erode the coastline. The softer River Command Words: (less-resistant) rock is eroded more quickly, forming a bay; e.g. the clay of Geology The type of rock that is : where layers of the rock run EG: The Bishopston river is formed of limestone Analyse - Take apart an idea, concept or statement and Swanage Bay. Deposition in the being eroded and the way in parallel to the coastline. So ratees of erosion are which is easily eroded. As a result large caverns and criticise it. sheltered bay forms a beach. which the rock types are laid even along the coastline. sink holes allow the river to run underground. The Assess - Come to a conclusion about the overall value or significance of • The more resistant rock is eroded more down will affect the rate of EG: Llyn river channel on the the surface is dry for the something; discuss its positive and negative aspects to show balance. 1 3 4 slowly and is left jutting out in to the change. majority of the time and the majority of erosions Compare - Identify similarities and differences. 2 7 sea forming a headland; e.g. the chalk 5 : occur underground. Define - State the meaning of an idea or concept. of Ballard Point. 6 Where bands of rock Describe - Set out the main characteristics of something; DON’T EXPLAIN. run at a 90o angle to the Discuss -Set out both sides of an argument (for and against) and come to a coast. This means conclusion; there should be some evidence of balance. erosion rates very. Evaluate - Make a judgement about the effectiveness of something; discuss its strengths and weaknesses and come to a conclusion about its overall 1) Swash moves sand up the beach at the angle of the prevailing wind EG: Abersoch Bay success or importance. 2) Backwash moves sand down the beach at 90° to the coastline, due to Explain - Give reasons why something happens. gravity Climate Will effect the rate of The prevailing wind affects the angle at which the The more water flowing into the river the higher Give - Produce an answer from recall. 3) This zig-zag movement of sand is called longshore drift and it change. This includes waves break along the coastline and therefore the the erosion rates will be. The highest erosion rates Justify - Support an idea or argument with evidence; for the outcome chosen, transports sand along the beach extreme weather events. direction of erosion and transportation. The waves in the UK are found in during the winter when there the positives must outweigh the negatives. 4) When the coastline changes direction, longshore drift deposits sand in break on the beach at this angle, pushing material is the most rainfall. State = name the sea up and across the beach. Therefore it effects where To what extent - Discuss and conclude how far you agree or disagree with a 5) This deposition causes the beach to extend out from the coastline, depositional landforms form. statement or view. forming a Beach – Deposition Human use Intended human activity Management of beaches where the coastline is left The River Thames is protected as it runs through 6) A change in the prevailing wind direction or ocean currents can form a A beach is a build up of sand and shingle and includes management exposed to erosion as the process of longshore urbanised areas. To prevent erosion on the outside Box = command word hooked (or recurved) spit pebbles deposited by waves. strategies to reduce the drift. banks of meanders, gabions are put in place to Underline = key words 7) In the sheltered area behind the spit, waves and rivers deposit and The swash needs to be stronger impact of erosion. EG: at Criccieth beach absorb wave energy absorb the power of the water. Glance = back sand forming mudflats and a saltmarsh Than the backwash. e.g. Spurn Head, Yorkshire as well as prevent longshore drift.