Rocks Resources And Scenery - Definitions Flashcards
Sedimentary rocks?
Most commonly, rocks formed from the accumulation of sediment on the sea floor
Metamorphic rocks?
Rocks that have undergone a change in their chemistry and texture as a result of heating and or pressure
Igneous rocks?
Rocks formed from the cooling of molten magma
Crust?
The outer layer of the earth
Geographical timescale?
The period of geographical time since life became abundant 542 million years ago which geologists have divided into eras and periods
What is the rock cycle?
Connections between the three rock types shown in the form of a diagram
Weathering?
The breakup or decay of rocks in their original place at or close to the earths surface (insitu)
Mechanical weathering?
Weathering that does not involve chemical change
Scree?
Deposits of angular rock fragments found at the foot of rock outcrops
Chemical weathering?
Weathering that involves a chemical change taking place
Biological weathering?
Weathering caused by living organisms such as tree roots or burrowing animals
Freeze thaw weathering?
Weathering involving repeated cycles of freezing and thawing
Pores?
Holes in rock
Exfoliation?
Flaking of the outer surface of rocks mainly caused by repeated cycles of hot and cold
Solution?
Dissolving rocks or minerals by rainwater
Carbonation?
Weathering of limestone and chalk by acidic rainwater
Batholith?
A huge irregular shaped mass of intrusive igneous rock that only reaches the ground surface when the overlying rocks are removed
Joints?
Cracks that may run vertically or horizontally through rock
Impermeable rock?
A rock that does not allow water to pass through it
Tor?
An isolated outcrop of rock on a hill top, typically found in granite landscapes
Mass movement?
The downhill movement of material under the influence of gravity
Vale?
In the landscape, a flat plain typically formed on clay
Cliff?
A steep or vertical face of rock at the coast
Permeable rock?
A rock that allows water to pass through it
Vale?
In the landscape, a flat plain typically formed on clay
Spring?
Water re-emerging from the rock onto the ground surface
Escarpment?
An outcrop of chalk comprising a steep scarp and a more gentle dip slope
Dry valley?
A valley formed by a river during a wetter period in the past but now without a river
Limestone pavement?
A bare rock surface, with a distinctive blocks (clints) and enlarged joints (grikes)
Swallow hole?
An enlarged joint into which water falls
Cavern?
A large underground cave
Resurgence?
A stream that emerges from underground
Stalacite?
An icicle-like calcite feature hanging down from a cavern roof
Stalagmite?
A stumpy calcite feature formed on a cavern floor
Pillar?
A calcite feature stretching from a floor to ceiling in a cavern
Curtain?
A broad deposit of calcite usually formed when water emerges along a crack in a cavern
Aquifer?
An underground reservoir of water stored in pores and or joints in a rock eg chalk
Syncline?
The lower arc of the fold in fold mountains
Aggregate?
Crushed stones made from tough rocks such as limestone used in the construction industry and in road building
Quarry restoration?
Restoring or improving the environmental quality of a quarry, either during its operation or afterwards
Vale?
In the landscape, a flat plain typically formed on clay
Cliff?
A steep or vertical face of rock at the coast
Permeable rock?
A rock that allows water to pass through it
Vale?
In the landscape, a flat plain typically formed on clay
Spring?
Water re-emerging from the rock onto the ground surface
Escarpment?
An outcrop of chalk comprising a steep scarp and a more gentle dip slope
Dry valley?
A valley formed by a river during a wetter period in the past but now without a river
Limestone pavement?
A bare rock surface, with a distinctive blocks (clints) and enlarged joints (grikes)
Swallow hole?
An enlarged joint into which water falls
Cavern?
A large underground cave
Resurgence?
A stream that emerges from underground
Stalacite?
An icicle-like calcite feature hanging down from a cavern roof
Stalagmite?
A stumpy calcite feature formed on a cavern floor
Pillar?
A calcite feature stretching from a floor to ceiling in a cavern
Curtain?
A broad deposit of calcite usually formed when water emerges along a crack in a cavern
Cement?
Mortar used in building, made from crushed limestone and shale
Aquifer?
An underground reservoir of water stored in pores and or joints in a rock eg chalk
Syncline?
The lower arc of the fold in fold mountains
Aggregate?
Crushed stones made from tough rocks such as limestone used in the construction industry and in road building
Quarry restoration?
Restoring or improving the environmental quality of a quarry, either during its operation or afterwards
Gorge?
Steep sided deep valley which may form by a cavern collapse
Explain the process of exfoliation?
1 during the day the sun heats up causing the rock to expand 2 at night the rock cools down and contracts 3 the repeated cycle of expansion and contraction causes the outer layers of rock to break off
What is the process of exfoliation also called?
Onion skin weathering
Where is exfoliation common?
In deserts
Why does rock not expand as much as the outside areas?
Rock is a poor conductor of heat
What is a negative environmental impact of hope quarry?
1 million tonnes of carbon dioxide
Social impact of hope quarry?
182 local people are employed in the quarry
Explain the process of carbonation?
Rainwater pick up carbon dioxide from the air Rainwater become a weak carbonic acid Acidic rainwater reacts with CaCO3 to form calcium bicarbonate which then dissolves
Where do the broken rocks at the foot of the tor come from?
Freeze thaw weathering
What encourages river deposition?
A river carrying a large load of sediment providing a lot of material for deposition A reduction in velocity eg the inside bend of a meander A fall in the volume of river water eg at times of low flow during drought An obstruction eh bridge supports interrupt flow
Explain the formation of a gorge?
Hard rock is underlain by soft rock. This erodes faster as a result of abrasion and hydraulic action. An overhang forms. This eventually collapses and the waterfall retreats upstream. This is how a gorge is formed, as the sequence repeats, a narrow, steep-sided valley is left where the waterfall used to be.
Explain the factors that influence discharge?
The amount of water will be high if the river is in an area with steep slopes. This will cause the water to run quickly over the surface due to gravity, before it has time to soak in. It will reach the river quickly and the amount of water will increase. The previous weather can also cause changes. If it has been dry, rain will soak into the ground and will be slow to reach the river. However, if it has been wet, the water will flow over the surface reaching the river quickly
Describe the formation of igneous rocks?
Igneous rocks are formed from molten magma. It may cool beneath the surface (intrusive), or on the surface (extrusive).
Give two characteristics of igneous rocks?
Igneous rocks can occur intrusively or extrusively because they are formed by magma cooling. They contain a variety or crystals. They are very hard and resistant to erosion. Coarse texture.
Describe the processes which lead to the formation of sedimentary rock?
- Rocks are weathered by a change in temperature - freeze thaw weathering. - This weakens the Rock and makes it easy for the small particles to be eroded. - Transported to rivers by sea, deposited on the sea bed. - Because of different material being deposited above this, the lower layers are compressed to form sedimentary rocks.
Describe the distribution of granite?
Granite is scattered around areas in Scotland and in South west England, there are pocket in Northern Ireland
Outline the characteristics of Carboniferous limestone? (2)
It is permeable It is formed in layers It is resistant to erosion Remains of Dead Sea creatures light grey
What is weathering?
Weathering is the effect of weather eg rain, change in temperature on rock. Weathering weakens rock and this occurs without any movement. Examples of weathering are chemical, biological and mechanical.
What are the underground features of Carboniferous limestone?
There are stalactites hanging from the ceiling - thinner and longer Stalagmites - shorter stubbier , corresponding Pillar - chunky , because where the two have joined
Formation of a stalactite?
Water in the cave contains dissolved calcium carbonate When this drips from the roof some evaporates and leaves behind tiny particles of re-deposited limestone. Stalactites (which look like icicles) form over hundreds of years
Formation of stalagmites?
Water drips on to the cave floor and a stalagmite forms in the same way as stalactite
Formation of a vale and escarpment
1 Hard chalk occurs next to softer clay. 2 Due to tectonic movement the chalk and clay are uplifted 3 Chalk is more resistant to erosion than clay as it is harder so it erodes slower and forms an escarpment 4 clays are less resistant so they form a lower lying vale. 5 The rocks are tilted and the steeper side is called a scarp slope 6 the sloping side is called the dip slope.
Describe a tor
Tots are isolated outcrops of rock with varied heights. Grey in colour. Rounded edges caused by chemical weathering Vertical joints which form when granite is cooled
What are the impacts of quarrying on an area?
- quarry provides jobs (maybe not many other jobs available) - boosts local economy - quarry’s are large and spoil the environment as there could be hills and waterfalls there so ruins them - heavy lorries create noise and congestion - dust pollution (breathing problems)
How can the impact of a quarry on the environment be reduced?
-At Paxton Pits the quarry has been turned into 77 hectares of grassland, lakes, shrubbery and woodland. - wildlife has been added such as kingfishers and peacock butterflies - 27km of new footpaths have been added - educational purpose centre eg pond dipping -nightingales have been bred here - roads cleaned at night - the Eden project also has an environmental charity - educational gardens - concert (Eden sessions) recently with dizzy rascal and the xx - 1,5 million tons of fill material have been relocated around the site to create the basic landforms
What physical landscape would you find in an area of granite rock?
- generally tors ( an isolated outcrop of rock on a hilltop) - wet and marshy, lots of rivers - areas with high rainfall, snow in winter - very few trees
How does granite affect the way the land is used?
- generally farmed with sheep/cattle - bad quality soil so only grazing by animals not much actual farming - beautiful land so tourism - people like to go walking, rock climbing, bird watching, mountain climbing/ Viking - army firing range
Uses of granite
- fireplaces, kitchens, gravestone - building - metals eg tin and copper are often mined in areas of granite
Uses of Carboniferous limestone
Tourism Outdoor pursuits Mountain biking Potholing Sheep grazing Caving
Give two characteristics of metamorphic rocks?
Tough - resistant to erosion Layering (not beds)
Example of : igneous metamorphic sedimentary
igneous - granite metamorphic - slate sedimentary - sandstone limestone
How long ago were Granite Carboniferous limestone Chalk formed?
Granite - 280 million years ago Carboniferous limestone - 340 million years ago Chalk - Carboniferous period
How are metamorphic rocks formed?
Altering sedimentary or igneous rocks by HEAT or PRESSURE
Difference between intrusive and extrusive rock?
unserground - intrusive above ground - extrusive
What are: Mechanical Chemical Biological weathering?
Mechanical: no chemical changes the breakup of rocks Chemical: chemical change occurs when weathering takes place Biological: - caused by living organisms such as TREE ROOTS
Describe the links of different types of rocks in the rock cycle?4
- igneous rock that is formed by magma cooling is weathered and eroded - these particles are deposited on the sea bed - over time the weight of additional layers of particles and the sea compress this material to create sedimentary - it can be subjected to heating to change to become metamorphic rock
Explain the formation of a limestone pavement?6
- rainwater is weak carbonic acid as it has carbon dioxide in it as it passes through the air - there is a reaction between calcium cabronate and the slightly acidic and this causes limestone to dissolve - this happens most when rainfall an reach calcium carbonate easily through the joints of the rock - the joints are enlarged to create the cracks of a limestone pavement - this leaves behind slabs of limestone - which can be different sizes depending on the pattern of the joints
What advantages are there for quarry’s to people?2
- provides jobs in areas were km there is little alternative other than low paid farming or seasonal tourism - they can stay in the area and spend money in local shops boosting the local economy
What disadvantages are there for quarry’s for people?4
- There will be noise from the blasting - heavy lorries go past causing traffic - dust will be present in roads and the air causing health problems and ruining the fresh air - scars the landscape
How/why is granite used in building?
- because it is hard
- resistant
- neutral colour
What can chalk be used for?
- for the production of cement
- to use in construction and road building
Case study facts for Dartmoor?
- 90% of the land is farmed
- For the past 5000 years it has been used for farming
Case study information for the Peak District? (chalk landscape)
- 2 million tons of limestone quarried each year
- 1.3 million tons of cement made from this
With an example, describe the land use of granite landscapes?8
- mountain biking
- water sports (eg sailing)
- farming (mainly sheep)
- tourism
- birdwatching
- mountain climbing
- walking
What is the soil like in granite, chalk, Carboniferous landscapes?4
Carboniferous and chalk: soil is too thin so used for sheep grazing Clay : too wet and heavy top plié so is used for dairy cattle Granite : poor and acidic so could be used for rough grazing
What are the uses of Carboniferous limestone?7
- used in building eg Houses of Parliament - fertiliser - climbing - mountain biking - caving - photography - potholing
Used of chalk areas?4
- popular with naturalists due to rich wildlife - it is quarries to be made into cement for building - sheep farming - hills are popular for horseriding
Used of clay?5
- used in bricks - for pottery - if properly drained ( as it is often be water logged) can be used for crops - could be used for sheep and cattle farming - not popular with tourists as areas are flat and featureless
