Presentation on theme: "Higher Lithosphere Introduction to Limestone[Date] Today I will: - Be able to explain what limestone is - Be able to describe the formation of a limestone."— Presentation transcript:
Higher 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
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 Higher 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 Higher Lithosphere
Higher Lithosphere 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. 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.