1. Rocks and the Rock Cycle

2. Objectives  Know of physical and chemical processes associated with rock formation  You should:  Understand the rock cycle  Know major rock types  Understand weathering and erosion

3. Rock Types  Igneous-made as magma/lava cools. Contains crystals  Sedimantary-made as rock particles/ parts of dead organisms build up as deposits  Metamorphic- when either of the above types are transformed by heat /pressure

5. http://www.youtube.com/watch?v=CvDw0 7iYaJQ http://www.youtube.com/watch?v=ihfKNRdlE2E

6. Weathering  Physical weathering occurs when rocks are consistently broken down into smaller and smaller pieces. Only the size changes not the chemical composition.  Chemical weathering is the process by which rocks are decomposed, dissolved or loosened  by chemical processes to form residual materials.

7. Water, wind, ice, and waves are the agents of erosion en.wikibooks.org Organicgardeningmagazine.info

8. scienceviews.com

9. Ice erosion in a glazier Melt water gets into cracks in the bedrock. The water freezes and expands opening up cracks. Meltwater freezes around lumps of broken rock and it is carried downhill with the ice, scraping the bedrock. www.geography. learnontheintern et.co.uk › geotopics › glaciation

10. m.eb.com

11. Chemical weathering  CARBONATION Here dissolved carbon dioxide in rainwater or moisture in air forms carbonic acid and reacts with the minerals in the rock. This process weakens the rock thus breaking it down in the process.

12. HYDROLYSIS  A chemical reaction occurs between the minerals in the rock and hydrogen in rain water.  For example, during hydrolysis, the feldspar in granite changes to claymineral which crumbles easily, weakening the rock and causing it to break down.

13. OXIDATION  Oxygen combines with water and minerals in the rock such as calcium and magnesium. When iron reacts with oxygen, reddish -brown iron oxide is formed. The iron-oxide crust crumbles easily and weakens the rock.  e.g Iron + Oxygen --> Iron Oxide (crumbles)

16. slate

18. lava

19. granite

20. limestone

21. gneiss

22. conglomerate