1. Limestone

2. 1. What is this?

3. 2. What is this?

4. 3. What is this?

5. 4. What is this?

6. 5. What is this?

7. 6. What is this?

8. 7. What is this?

9. 1. A gorge 2. A stalactite 3. A limestone pavement 4. A resurgence 5. A stalagmite 6. A gorge 7. A pillar

10. Remember this equation: Calcium carbonate (limestone) + Rainwater + Carbon dioxide Calcium bicarbonate Weak carbonic acid

11. Pervious rock Water dissolves rock Solution reaction equation Dissolves to form cavern Increases over time Cavern roof collapses Forms gorge with stream and scree at bottom How is a gorge formed? Plan:

12. Limestone is a pervious rock meaning that it has joints and bedding planes . Water travels along these joints and bedding planes and dissolves some of the rock by solution weathering. Calcium carbonate + Rainwater + Carbon dioxide Calcium Bicarbonate . This reaction continues over a long period of time and a cavern is formed. The cavern grows in size due to the continuous weathering. Eventually the cavern roof can no longer be supported and it collapses. This forms a steep-sided gorge with a stream running at the bottom of it. The broken fragments of rock form scree at the bottom.