3. Chaotic melange formed by subduction of oceanic crust Fig. 17.11

4. GabbroBasalt Eclogite

6. Increasing metamorphic grade

7. Hvilke endringer skjer i en bergart under metamorfose ? Teksturelle endringer Mineralogiske endringer Strukturelle endringer Kjemiske endringer

8. Fig. 7.7

9. Progressive Metamorphism Fig. 7.8

10. Controlling factors during metamorphism Temperature Pressure / stress Fluids

11. How do pressure and temperture vary in the lithosphere ?

12. Fig. 7.14 Metamorphic Facies

13. Chaotic melange formed by subduction of oceanic crust Fig. 17.11

14. Fig. B7.2

16. Marble Limestones

17. Metamorphism Quartzite Sandstone

19. Fig. 7.3A Granite

20. Fig. 7.3B Gneiss

21. Uniform and Differential Stress Fig. 7.3

22. Fig. 7.4 Flattened conglomerate

23. Fig. 7.3 GraniteGneiss

26. Fig. 7.5 Foliation through a microscope

27. Fig. 7.6C Slaty metamorphic cleavage

28. Fig. 7.6C Regional stresses

29. Fig. 7.6 Formation of Slaty Cleavage

30. Undeformed Granite Fig. 7.11A Xenolith

31. Foliated Gneiss Fig. 7.11B

32. Fig. 7.9 Metamorphosed Basalt

33. The role of fluids

34. Fluids fill all pores in a metamorphic rock Reduces effective stresses on the grain-grain contacts - thus favouring brittle deformation Speeds up reactions through –Increasing transport rates –Reduce activation energy for mineral reactions (ie. Acts as a catalyst)

36. Prograde metamorphism produces fluids A= B+H 2 O Retrograde metamorphism consumes fluids B+H 2 O=A Thus dry rocks need external fluid supply to undergo retrogressive metamorphism

40. Prograde metamorphism I Contact metamorphic mudstone in Karoo, South Africa

42. Types of metamorphism Regional metamorphism Contact metamorphism Burial metamorphism Hydrothermal metamorphism Shock metamorphism

43. Plate Setting and Metamorphism Fig. 7.16

44. Subduction and Copper-rich Mineral Deposits Fig. 7.17

45. Regional Metamorphism and Metamorphic Zones in the Scottish Highlands Fig. 7.13b Copyright 2000, John Wiley and Sons, Inc, all rights reserved

46. Fig. 7.13A Copyright 2000, J, Wiley and Sons, Inc, all rights reserved Regional Metamorphic Zones, Michigan

47. Contact Metamorphism adjacent to a Granite Intrusion Fig. 7.12

48. Fig. 7.15 1 centimeter Metasomatically altered Marble

50. Fig. B7.1 Garnet garnet-biotite schist 2 mm

51. Hydrothermal Alteration Fig. B7.4

52. Fig. B7.5 Submarine hot springs