2. 185’x88’ draft 25’

3. Sea State 6

7. Worked example - Here is the electron configuration for a filled fifth shell: ShellSubshellOrbitals Electrons n = 5l = 0m = 0→ 1 type s orbital→ max 2 electrons l = 1m = -1, 0, +1→ 3 type p orbitals→ max 6 electrons l = 2m = -2, -1, 0, +1, +2→ 5 type d orbitals→ max 10 electrons l = 3m = -3, -2, -1, 0, +1, +2, +3→ 7 type f orbitals→ max 14 electrons l = 4m = -4, -3 -2, -1, 0, +1, +2, +3, +4→ 9 type g orbitals→ max 18 electrons Total: max 50 electrons a shell can contain up to 2n² electrons

8. Igneous rocks – ignis Latin for fire

9. Locations of world’s volcanoes (on land) What is heat source?

11. Volcanism is governed by plate tectonics What is the biggest source of new material?

12. Igneous rocks on Earth #1 – Mid-ocean ridges (divergent) #2 – Subduction zones (convergent)

13. What causes an eruption….anywhere?

14. Increasingheat,pressure

15. Decompression melting

16. Volatiles decrease melting temperature

17. What causes an eruption….anywhere? 1. Decompression melting 2. Volatiles decrease melting temperature

18. So why do we have different volcanic rock types?

19. 4 (common) extrusive igneous rocks Basalt Andesite Rhyolite Komatiite

20. Where do chemical differences arise?

21. Magma chamber processes

22. So why do we have different volcanic rock types? Source material the same: mantle-derived Magma chamber processes: 1. Magmatic differentiation (Bowen’s Reaction Series) 2. … 3. …

23. TRAIL MIX MODEL OF MAGMA FORMATION Initial composition: 25% M&Ms 25% Raisins 25% Peanuts 25% Almonds

24. TRAIL MIX MODEL OF MAGMA FORMATION 2nd composition: 25% M&Ms 33% Raisins 33% Peanuts 33% Almonds

25. TRAIL MIX MODEL OF MAGMA FORMATION 3rd composition: 25% M&Ms 33% Raisins 50% Peanuts 50% Almonds

26. Magma crystallizes through 200°C+ of temperature Magmatic differentiation

27. Scenario A: young, hot magma

28. Initial melt composition: 1. Olivine 2. Pyroxene Ca-rich plagioclase feldspar 3. Amphibole Intermediate plagioclase feldspar 4. Biotite mica Na-rich plagioclase feldspar

31. Scenario B: magma sits around, cools

32. 2nd melt composition: 1. Olivine 2. Pyroxene Ca-rich plagioclase feldspar 3. Amphibole Intermediate plagioclase feldspar 4. Biotite mica Na-rich plagioclase feldspar

35. Scenario C: (relatively) old, cold magma

36. 3rd composition: 1. Olivine 2. Pyroxene Ca-rich plagioclase feldspar 3. Amphibole Intermediate plagioclase feldspar 4. Biotite mica Na-rich plagioclase feldspar

39. So why do we have different volcanic rock types? Source material the same: mantle-derived Magma chamber processes: 1. Magmatic differentiation (Bowen’s Reaction Series) 2. … 3. …

41. So why do we have different volcanic rock types? Source material the same: mantle-derived Magma chamber processes: 1. Magmatic differentiation (Bowen’s Reaction Series) 2. Assimilation 3. Magma mixing take a long time ~ imply distance from source

42. How can you predict where you’ll find different rock types?

43. Which magma sits around longest?

44. Which magma has to travel farthest?

45. So why do we have different volcanic rock types? Source material the same: mantle-derived Magma chamber processes: 1. Magmatic differentiation (Bowen’s Reaction Series) 2. Assimilation 3. Magma mixing take a long time ~ imply distance from source

46. Youngest magma ~ Closest to source Oldest magma ~ Farthest from source

47. Divergent Boundary Mid-Ocean Ridge Continental rift (Hot spots) Convergent Boundary Continental/ Island Arcs Intra-continentalYellowstoneTaupo

48. Divergent Boundary Mid-Ocean Ridge Continental rift (Hot spots) Convergent Boundary Continental/ Island Arcs Intra-continentalYellowstoneTaupo Most Explosive Least Explosive

49. Most Explosive Least Explosive Rhyolite PeridotiteGabbroDioriteGranite AndesiteBasalt Komatiite Extrusive Intrusive