Upland Limestone Flashcards
What are the 6 marks for how a limestone pavement is formed?
• Limestone is made from the decayed remains of sea creatures
Laid in horizontal layers on sea beds (bedding planes). These sedimentary rocks were uplifted and cracks appeared as the rocks dried out (joints).
- During glaciation, ice scraped away all the topsoil and exposed the bare rock underneath.
- The dry, well-jointed (permeable) bare rock surface allows water to seep into it. (Add diagram 1).
- When CO2 in the atmosphere mixes with the rain a weak carbonic acid is made and this reacts with the limestone and dissolved the rock(carbonation). The dissolved limestone is carried away by running water (solution).
- Continued chemical weathering widens and deepens cracks to form gaps called GRIKES.
- Rectangular blocks of limestone called clints are separated by the grikes.
- Could also talk about PW of freeze-thaw and how this makes grikes bigger and how the pieces of broken rock fall down the valley forming a scree slope.
What are Joints?
Vertical cracks in a rock formed when the rock dried out or pressure is released, before weathering of limestone.
What are bedding planes?
Horizontal blocks / layer is sedimentary rock before weathering of limestone.
What are grikes ?
Enlarged joints which are vertical gaps/cracks in a limestone pavement and occur after weathering.
What are Clinks?
Horizontal blocks of limestone in a limestone pavement.
The formation of swallow holes?
- Limestone is permeable and so any river flowing along a limestone pavement will quickly disappear underground.
- The point at which this happens is a swallow hole.
- These occur where joints have been enlarged
How does intermittent drainage occur?
The bonds of different rock is impermeable meaning water can’t pass through
How do caves/caverns form (4 marks)?
- Limestone contains both joints and bedding plains, splitting the rock into well-defined rocks and making it permeable.
- Water flows underground through a swallow hole, along bedding planes and down joints until it reaches impermeable rock.
- As it does so its slight acidity dissolves the limestone it comes in contact with.
- A cave/cavern forms when there is money joints and bedding planes close together so large areas of rock in the same area dissolve quickly.
- This leaves a large space underground which is called a cave/cavern.
- Some cave systems may also have been affected by changes to the climate.
Explain the formation of stalactites/stalagmites?
- CO2 MIXES with rainwater in the ATMOSPHERE to form a WEAK CARBONIC ACID .
- As limestone is a PERMEABLE rock it is CHEMICALLY WEATHERED through the joints and bedding planes of a limestone pavement by the weak carbonic acid.
- The chemical composition of limestone is CALCIUM CARBONATE therefore as the water SEEPS through the permeable rock and into the caves/caverns below it becomes LACED with the calcium carbonate from above.
- The water trickles along the ceiling of the cave and drips to the floor. Due to the heat within the cave the water is EVAPORATED leaving behind calcium carbonate deposits on both the ceiling and floor of the caves.
- Over many years this calcium carbonate builds up to create icicle shaped features called STALAGMITES (which are found in the floor of the cave and STALACTITES (which are found on the ceiling of the cave.
- Stalagmites tend to be THICKER than stalactites as there is more calcium carbonate deposited due to the drip of water spreading as it hits the floor.
Give 4 reasons why/how hill sheep farming is a major land use in the Yorkshire dales?
- It is very cold and wet which means that only hardy animals like hill sheep can be farmed and survive the harsh conditions
- The slopes are very steep which means that it would be very hard to get machinery up fields to harvest crops
- Very thin and infertile soil which can even be non existent in some parts and the fact that as limestone is permeable there’s is little water at the surface for roots to reach, means that growing crops is really hard and not economically feasible plus
- Poor cold very wet conditions with little sunshine mean that growing season is very short meaning that growing crops is very hard and not economically feasible.
Who/Why does industry use upland limestone landscapes?
Quarrying is often an important industry in upland landscapes. In the Yorkshire dales the main rock quarried are Carboniferous limestone, sandstone and gritstone. Cement workers can also set up here due to the raw material lime.
Give 6 reasons why/how tourism uses upland limestone landscapes?
- To see the distinctive landscape, fore example: limestone pavements, scars and potholes.
- Visitors like to enjoy the experience of idyllic rural villages.
- People like to visit caves like white scar caves in the Yorkshire Dales to admire the dripstone features.
- Hill walking in the uplands and cycling in the valleys are common activities.
- Abseiling down limestone scars is a popular activity.
- Other activities such as horse riding, potholing are popular in limestone areas.
What are the 6 conflicts between tourism and industry in an upland limestone landscape?
- Quarries are an eyesore on the landscape and spoil the natural beauty of the area.
- Lorries that remove quarried rocks cause vast amounts of air pollution which can lead to visual pollution.
- Large lorries that move the quarried rocks Cassie huge traffic congestion on small, narrow country roads.
- Blasting of rocks causes noise pollution.
- Some wildlife habitats may also be destroyed.
- Quarries can leave a scarred landscape when they are finally abandoned.
What are the 6 conflicts between locals and tourists?
- Limestone pavements suffer from wear and tear and from the removal of stone due to the severe number of visitors.
- Severe traffic congestion near to main attractions limits the movement of locals especially during peak times.
- An increase in vehicles results in a build up of air and noise pollution from car exhausts
- The demand for car parking exceeds the number of spaces provided resulting in parking on grass verges.
- Footpaths have been eroded, particularly in the areas around Malcolm Cove.
- House prices in the area increase, partly because of income wishing to live there and due to the demand for second homes. Resulting in first time buyers being unable to get onto the property ladder.
What is the solution to the conflict between tourist and industry of : quarries being an eyesore and spoiling the natural beauty of the area?
National park authorities can insist on companies screening quarries with trees to reduce visual pollution.
