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Lithosphere
Introduction to Limestone
[Date]
Today I will:
- Be able to explain what limestone is
- Be able to describe the formation of a limestone
pavement
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Lithosphere
What is limestone?
- It is a sedimentary rock
- It was formed mainly from sea shells
- It is the compound called calcium carbonate
-It is a useful raw material
- Limestone is dug up out of the ground
in quarries
- In Britain about 150 million tonnes of
limestone are quarried each year
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Lithosphere
What is limestone used for?
- Building walls
- Building houses
- Limestone is also used to make cement
and concrete
- Neutralising excess acid in lakes or soils
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Lithosphere
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Lithosphere
Limestone Pavement
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Lithosphere
Limestone Pavement
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Lithosphere
Limestone Pavement
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Lithosphere
Carboniferous limestone is
made of blocks of rock. The
clear horizontal lines are called
planes and the vertical cracks
are called joints. The rock is
permeable which means water
can pass through the lines of
weakness - the bedding planes
and joints.
Rainwater is a weak carbonic acid which reacts with the limestone as it passes through
the rock. It dissolves the stone, enlarging joints and bedding planes. On the surface the
chemical weathering widens and deepens cracks to form grykes. This leaves exposed
blocks of limestone called clints and the resulting pattern of blocky rock is called a
limestone pavement.
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Lithosphere
Sink Hole
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Lithosphere
Sink Hole/Swallow Hole
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Lithosphere
Pot Hole