Limestone Flashcards
What is limestone?
Sedimentary rock (formed from pieces of rock, usually formed in water)
What is limestone made of?
- Calcium carbonate
- CaCO3
What is freeze-thaw weathering?
- Causes rocks to break. Involves water getting into gaps in the rock.
- Freezes when tempreture drops, expanding causing rock to break
What is chemical weathering?
Weathering caused by chemicals in the air and rainwater
What is acid rains effect on limestone?
- When acid rain falls on limestone a chemical reaction takes place
- Stone changes into CO2, H2O and Ca salt
Where was limestone laid down?
In layers on the sea bed
What are the junctions between the layers called?
Bedding planes
What are the weaknesses in the layers called?
Joints
What does permeable mean?
Water can pass through the rock
Where does the acid rain dissolve the limestone?
Where it is weak, along the joints
Another name for a limestone pavement?
Karst landscape
What is a clint?
Top, flat pieces of the limestone
What is a grike?
Joints or cracks between clints / scar
How are stalactites, stalagmites and pillars formed?
- Water drips from roof of caverns and evaporates. Solid calcium carbonate is deposited on cavern roof
- Build-up over time forming long, thin stalactites which grow downwards
- Some drops of water splash on cavern floor
- splash spreads depositing CaCO3, which builds up stalagmites
- When a stalactite and stalagmite meets it creates a pillar
How is intermittent drainage formed?
- When stream disappears through permeable limestone, travels underground through complex series of caves
- Works its way down to level of impermeable rock
- Stream flows until it reaches surface as a spring
How is a swallow hole formed?
- A stream travelling over an impermeable rock will quickly when it has to travel over limestone
- These swallow holes can be many meters deep leading down to a series of underground features
How is a gorge formed?
- Near vertical rock cliffs along the sides of valleys
- Formed by caves collapsing
How are caverns formed?
Some of the underground limestone dissolves quicker than rock around it
Explain farming land use
Hill sheep farming
- cold and growing season is short
- little water near surface
- unsuitable for crops
Explain tourism land use
Attracted to interesting & unusual scenery, hill walking
- brings over £320m
- brings over 8k jobs
Explain quarrying land use
Limestone, gritstone
- limestone: steelworks, chemical, cement industries
- gritstone: cement works
Explain military land use
Upland areas
- suitable training areas
- doesn’t take farmland
- fewer people around
Explain conflict of land use between: quarrying vs locals
- Traffic congestion and narrow roads
- closed quarries can be dangerous
: restriction of trucks moving at certain times of day
: promote rain transport
: covering lorries to reduce dust
: make site secure
: warn children
Explain conflict of land use between: quarrying vs farmers
- Dust and waste from quarries get into water and make unsuitable water
- noise can scare animals eg. lambing sheep
: pass legalisation prevents quarries from dumping untreated waste into rivers
: fines used to inforce measure
: restrict blasting during lambing season
