1. Historical Geology Lecture 11 The Proterozoic Eon

2. Historical Geology IProterozoic Timeline IITectonics Overview A)Continental Growth B)Wilson Cycle Tectonics IIIPaleoproterozoic Laurentia (North America) A)Orogenies (Convergence) B)Rifting (Divergence) C)Sedimentation D)Climate IVMesoproterozoic Laurentia (North America) A)Orogenies (Convergence) B)Rifting (Divergence) C)Sedimentation D)Climate VNeoproterozoic Laurentia (North America) A)Orogenies (Convergence) B)Rifting (Divergence) C)Sedimentation D)Climate VIThe Proterozoic Outside Laurentia Outline

3. Historical Geology The Proterozoic Eon 1.0 bya 2.5 bya 1.6 bya 0.545 bya

4. Historical Geology The Proterozoic Eon Tectonics Overview growing cratons lateral plate tectonic movements rifting and sea-floor spreading wide continental shelves epeiric seas

5. Historical Geology The Proterozoic Eon Aggregating Cratons accretion - addition of crustal materials to continental margins aggregation – bringing together and consolidation of cratonic elements

6. Historical Geology The Proterozoic Eon Early Epeiric Seas epeiric sea - a shallow sea flooding the continental craton Erikkson, et al., 1998

7. Historical Geology The Proterozoic Eon Sedimentation Overview Carbonates appear Banded Iron Formations peak/disappear Red Beds Passive Margin Sedimentation

8. Historical Geology The Proterozoic Eon Carbonate Sedimentation

9. Historical Geology The Proterozoic Eon Banded Iron Formations

10. Historical Geology The Proterozoic Eon Red Beds oxidation 4Fe + 3O 2 ---> 2Fe 2 O 3 iron + oxygen -> iron oxide hematite limonite laterite soils Red Shale Chuar Group (Grand Canyon)

11. Historical Geology Paleoproterozoic Laurentia Orogenies Torngat (2.1-1.75 Ga) Taltson-Thelon (2.0-1.9 Ga) Penokean (2.0-1.8 Ga) Wopmay (1.97-1.84 Ga) Cape Smith-New Quebec (1.9-18 Ga) Trans-Hudson (1.88-1.79 Ga)

12. Historical Geology Paleoproterozoic Laurentia Slave Province

13. Historical Geology Paleoproterozoic Laurentia Slave Province Aulacogens Athapuscow Aulacogen Bathhurst Aulacogen Irving, et al., in press

14. Historical Geology Paleoproterozoic Laurentia Slave Province - Wopmay Orogen

15. Historical Geology Paleoproterozoic Laurentia Superior Province Young, 2002 Ojakangas, et al., 2001

16. Historical Geology Paleoproterozoic Laurentia Superior Province - Huronian Supergroup Young, 2002 2.5 - 2.2 Ga Gowganda Formation Huronian Supergroup Gowganda Tillite

17. Historical Geology Paleoproterozoic Laurentia Glaciation

18. Historical Geology Paleoproterozoic Laurentia Superior Province - Animikie Group 2.2 - 1.8 Ga Young, 2002 Banded Iron Formation Animikie Group Kona Dolostone Animikie Group Ajubik Quartzite Animikie Group

19. Historical Geology Paleoproterozoic Laurentia Superior Province - Penokean Orogeny

20. Historical Geology Paleoproterozoic Laurentia Superior Province Cross Section

21. Historical Geology Paleoproterozoic Laurentia Trans-Hudson Orogen Schwerdtner and Cote, 2001

22. Historical Geology Mesoproterozoic Laurentia Events Elsonian Orogeny Yavapai Orogeny Mazatzal Orogeny Mid-Continent Rifting Grenville Orogeny Assembly of Rodinia

23. Historical Geology Mesoproterozoic Laurentia Yavapai and Mazatzal Orogenies Series of orogenies ~1.8 - 1.6 Ga Vishnu Schist

24. Historical Geology Mesoproterozoic Laurentia Grand Canyon Region

25. Historical Geology Mesoproterozoic Laurentia Grand Canyon Region

26. Historical Geology Mesoproterozoic Laurentia Mid-Continent Rift ~1.2-1.0 Ga Keweenawan Supergroup Ojakangas and Dickas, 2002

27. Historical Geology Mesoproterozoic Laurentia Grenville Orogeny

28. Historical Geology Mesoproterozoic Era Rodinia S W E A T A U S W U S

29. Historical Geology Mesoproterozoic Era Rodinia – SWEAT

30. Historical Geology Mesoproterozoic Era Rodinia – AUSWUS

31. Historical Geology Neproterozoic Laurentia Breakup of Rodinia Panthalassic Ocean (proto-Pacific) Iapetus (proto-Atlantic) Varangian Glaciation Eykes and Januszczak, in press

32. Historical Geology Neproterozoic Laurentia Breakup of Rodinia

33. Historical Geology Neproterozoic Laurentia Panthalassa

34. Historical Geology Neproterozoic Laurentia Late Proterozoic Rifting Grand Canyon Supergroup

35. Historical Geology Neproterozoic Laurentia Grand Canyon Supergroup

36. Historical Geology Neproterozoic Laurentia Late Proterozoic Rifting Breakup of Rodinia Panthalassic Ocean (proto-Pacific) Varangian Glaciation

37. Historical Geology Neproterozoic Laurentia Late Proterozoic Rifting

38. Historical Geology Neproterozoic Laurentia Varangian Glaciation

39. Historical Geology Neproterozoic Laurentia Varangian Glaciation OXYGEN Heavy Oxygen-18 is incorporated into minerals. More Oxygen 18 during low temperatures. STRONTIUM Increased Sr86/87 ratio due to increased weathering during glaciation. CARBON 12/CARBON 13 Plants use the lighter isotope Carbon 12 in photosynthesis. The lower relative abundance of Carbon 13 means the plants were worse off (dying). Evidence in “cap” carbonates Jacobson and Kaufmann, 1999 Knoll, 2000

40. Historical Geology Neproterozoic Era Snowball Earth

41. Historical Geology Neproterozoic Era Snowball Earth

42. Historical Geology Neproterozoic Era Snowball Earth

43. Historical Geology The Precambrian Outside North America