1. Late Paleozoic Earth History http://jan.ucc.nau.edu/~rcb7/270_1st.jpg

2. Early Paleozoic Marine conditions in North America Major orogenies –Taconian orogeny in Ordovician

3. Late Paleozoic Devonian, Carboniferous, and Permian periods “Carbon-bearing” – worldwide coal deposits Mississippian and Pennsylvanian used only in North America –Mississippian – last widespread carbonates in North America –Pennsylvanian – coal deposits

4. For the Late Devonian Period Paleogeography of the World

5. For the Early Carboniferous Period Paleogeography of the World

6. For the Late Carboniferous Period Paleogeography of the World

7. For the Late Permian Period Paleogeography of the World

8. The Late Paleozoic cratonic history of North America included –extensive shallow-marine carbonate deposition –large coal-forming swamps –dry, evaporite-forming terrestrial conditions Late Paleozoic History of North America

9. Paleogeography of North America during the Devonian Period Devonian Period

10. Devonian Sedimentation

11. Organic Reefs http://www.holchanbelize.org/zonea.html

12. Organic Reefs

13. Devonian Reef

14. Evaporites Evaporation of large volumes of water causes salts to precipitate Extensive in Silurian and Devonian

15. Two Evaporite Environments Restricted basin –seawater washed over bar, cannot escape –hypersaline solution forms Supra-tidal –few cm above average high tide –occasionally flooded

16. Two Evaporite Environments

17. Michigan Basin >1.5 km of evaporite deposits Rock salt, dolomite, anhydrite Probably a restricted basin Mined for plaster and chemical industry

18. Michigan Basin

19. Another Orogeny on East Coast Acadian orogeny in Devonian Superimposed on Taconian orogeny in same location Catskill clastic wedge

20. Plate Tectonics and Evolution Lots of mountain-building in Devonian created significant amount of land above SL Coincided with evolution of land plants and animals

21. Paleogeography of North America during the Mississippian Period Mississippian Period

22. Cross-bedding, ripple marks, and well- sorted fossil fragments Indicative of a shallow-water environment Analogous to present-day Bahama Banks Mississippian Carbonates

23. Paleogeography of North America during the Pennsylvanian Period Pennsylvanian Period

24. Coal Swamps Low coastal plain swamps next to Appalachian Mountains Accumulation and burial of tons of plant material Modern analogs: Florida Everglades, south Louisiana swamps

25. Pennsylvanian coal bed, West Virginia part of a cyclothem Pennsylvanian Coal Bed

26. The Okefenokee Swamp Georgia - modern coal-forming environment, similar to those of the Pennsylvanian

27. Modern coal-forming environments the Mississippi delta the Okefenokee Swamp, Georgia the Florida Everglades and the Dutch lowlands By studying these modern analogues, geologists can make reasonable deductions about conditions existing in the geologic past Modern Analogues

28. The age of the coals in the Midwestern states and the U.S. Coal Deposits Appalachian region are mostly Pennsyl- vanian Those in the west are mostly Cretaceous and Tertiary

29. The assembly of Pangaea –completed during the Permian –result of the many continental collisions that began during the Carboniferous The Permian Period

30. The formation of a single large landmass had climatic consequences for the continent Terrestrial Permian sediments indicate that arid and semiarid conditions were widespread over Pangaea Climatic Consequences The mountain ranges were high enough to create rain shadows that blocked the moist, subtropical, easterly winds much as the southern Andes Mountains do in western South America today

31. Paleogeography of North America during the Permian Period Permian Period

32. Early Permian Shallow sea still covered western United States and SW Texas Organic reef complex flourished at edge of 300 m deep basin El Capitan – massive reef core

33. Location of the west Texas Permian basins and surrounding reefs Permian Reefs and Basins

34. Guadalupe Mountains www.rozylowicz.com/retirement/guadalupe/guadalupe.html

35. El Capitan www.rozylowicz.com/retirement/guadalupe/guadalupe.html Massive reef at edge of basin

36. Permian Basin Prolific oil producer Ancient basins near reef – source of organic material Deformation during Late Paleozoic provided trapping structures

37. Also in Permian Widespread evaporites and red beds Indicate arid conditions as shallow seas retreated and evaporated More land than ever before – collisions and mountain-building events

38. How did this affect North America? Ancestral Rockies Marathon uplift of West Texas Ozarks and Ouachitas Great Smoky Mountains Appalachians (for the third time)

39. Permian reefs and other strata in the western United States, particularly Texas, –have also been prolific producers Hydrocarbons