Upland Limestone Flashcards
Explain the formation of a Limestone Pavement.
During glaciation, ice scraped away the top soil. This process is known as abrasion and it exposed the bare rock underneath. Today, the dry, well-jointed bare rock surface allows water to seep down it. Acidic rainwater (a weak carbonic acid) reacts with the limestone as it passes through the permeable rock. It dissolves the rock, enlarging the cracks and making them wider and wider. Continued chemical weathering widens and deepens cracks to form gaps called grikes. Rectangular blocks of limestone called clints are separated by the grikes. The resulting pattern of block-like rock is called a limestone pavement.
Explain the formation of swallow hole/potholes.
When a stream flows onto limestone it enlarges the joints in the rock. Water seeps down through the rock layers where the joints have been extensively enlarged by chemical weathering. Eventually, the stream will disappear down a hole and flow along underground channels. The resulting hole in the surface of the landscape is called a swallow hole.
Intermediate Drainage.
If limestone is capped by impermeable rock, surface streams can run onto limestone. As limestone is permeable, the water disappears from the surface, either by seeping through joints in the limestone or as streams disappearing down swallow holes. The underground stream will flow down through the limestone until it reaches an impermeable rock eg millstone grit. It will emerge at the surface where the water can no longer pass through it to disappear underground.
What is a Scar?
Scars are exposed cliffs of limestone. They were created during the last ice age, when huge sheets of ice scraped away the soil-covered spurs in many valleys in the Yorkshire Dales.
Explain the formation of Caverns.
Small caves develop where joints and bedding planes are close together. They form when underground streams are very effective at weathering and eroding the limestone. The water dissolves the limestone along the joints and bedding planes more quickly than the rock around it. Larger caverns form when the roof of a cave collapses. They can also be enlarged by the usual processes of river erosion - hydraulic action, corrosion and corrasion.
Explain the formation of stalagmites and stalactites.
When water flows underground it is loaded with dissolved limestone. Water drips from the roof of a cavern. When the water evaporates tiny amounts of solid calcite are deposited on the cavern roof. These deposits build up over a very long period of time and form features called stalactites which hang down from the ceiling of a cavern. Some drips of water drop on the floor and some of it splashes and evaporates. The splash spreads the deposit of calcite on the cavern floor. As more and more calcite builds up, short and dumpy features grow upwards from the ground. These are called stalagmites. Occasionally stalagmites and stalactites meet to form a rock pillar.
Describe/list land uses appropriate to upland limestone landscapes.
Hill sheep farming is the most common type of farming in upland areas . Sheep are hardy and can survive the harsh weather conditions and poor-quality grazing. Many farmers have diversified to non-farming activities to create more income eg bed and breakfast facilities.
Quarrying in the Yorkshire Dales is an important industry and around 4.5 million tonnes of rock are quarried each year. The main rocks quarried are carboniferous limestone, sandstone and gritstone.
Millions of people visit the Yorkshire Dales every year to appreciate the distinctive scenery, e.g. Ingleton waterfalls, Malham Cove and Gordale Scar. Visitors enjoy the experience of traditional idyllic rural villages such as Malham. The Dales Countryside Museum enables visitors to find out about the history of the area. People visit limestone caves, e.g. White Scar Caves to admire the dripstone feature such as the Devil’s Tongue. Ancient semi-natural woodland in Freeholders’ Wood has trails for walkers and a variety of wildlife to see. Hill walking is a popular activity and there are a number of footpaths including the Pennine Way and Ingleborough Hill. Many other activities such as caving, pot holing, rock climbing, cycling and horse riding are also popular in the Yorkshire Dales.
What are the conflicts between tourists and industry (quarrying)?
Tourists visit the Yorkshire Dales National Park to see the beautiful and unusual scenery. Unfortunately, quarries spoil the natural beauty of the landscape, endanger wildlife and put visitors off returning to the area. This threatens local tourism-related jobs eg in shops and restaurants. The large lorries needed to remove the quarried stone cause air pollution which spoils the atmosphere for tourists. Lorries also cause traffic congestion on narrow country roads which slows traffic and frustrate drivers. The blasting of rocks creates noise pollution, disturbing the peace and quiet for visitors. Some wildlife habitats may also be disturbed by the removal of rock. Quarries can leave a scarred landscape when they become disused.
Which solutions have been made to resolve these issues between industry’s and tourists?
National Park Authorities can refuse planning consents for new quarries but they can’t close existing ones.
Rail transport is encouraged to reduce the number of lorries on roads. Lorry loads are also covered to reduce dust emmisions.
Some nature reserves are located away from quarries to protect wildlife.
What are the conflicts between tourists and locals in the Yorkshire Dales?
The large volume of visitors means that limestone pavements suffer from wear and tear. Local roads suffer from traffic congestion, particularly near main attractions like Malcolm Cove. There is increased air pollution from tourists’ car exhausts. Noise pollution from too many people and cars disturbs the peace and quiet in local villages. Footpaths have been eroded around tourist attractions. Tourists litter spoils the natural beauty of the area.
Which solutions have been put in place between the conflicts or tourists and locals and the Yorkshire Dales?
National park legislation and rules are in place to protect limestone pavements.
Park wardens patrol and monitor the use of footpaths.
The use of public transport such as Dales Bus Services is promoted to reduce traffic congestion.
