1. Denudation
Lesson Plan

2. What is denudation?
The shaping of the earth

3. What shapes the land?

4. Denudation processes Weathering erosion mass wasting/ mass movement
What are they?

5. What is weathering?
Processes leading to disintegration and decomposition of rock
in situ processes

6. How does the rock break up?
1. Mechanical weathering/ Physical weathering
2. Chemical weathering
3. Biotic / Biological weathering

7. Mechanical weathering
Caused by
temperature changes
unloading brought about by denudation
salt crystal growth

8. Block Disintegration
With repeated expansion and contraction, the rock breaks up along joints

9. A Disintegrated block

12. Exfoliation

13. Rock peels off

14. Granular disintegration

15. Chemical weathering
Decomposition of rock caused by rain, air (e.g. Carbon dioxide) and organic acids.
Active in hot and wet areas

16. What Chemical Processes?
Solution
Hydration
Hydrolysis
Oxidation
Carbonation
How do they act on rock?

17. Honeycomb weathering

18. They are always found near the coast. Why?

19. Spheroidal weathering
Partially weathered core-stone
Totally weathered outer layer

20. Biotic/ Biological Weathering
Physical break up of rock by plant roots or burrowing animals
Chemical decay of rock facilitated by organic acid produced by plants and animals

21. Weathered granite in HK