1. Early Paleozoic Geology

2. Basic Rules of Geology • Transgression • rise in sea level • Regression • lower in sea level • Convergence leads to orogeny • Orogeny leads to erosion

3. Continental Architecture • Stable, immobile part of a continent • Craton • Mobile Belt • Located along continental margins, receive sediments, and deform during collision • i.e., Franklin, Corilleran, Quachita, Appalachian • Epeiric Seas • Widespread shallow seas that transgress and regress over the continent

4. Phanerozoic Eon • Phanerozoic – comprises 12% of all geologic time • Paleozoic Era – 6.5% of all geologic time

5. Paleozoic Eon Introduction • 6 major continents were present – as well as several microcontinents and island arcs • Deposition due to transgressions and regressions • Mountain building (orogeny) due to collision of continents

6. Early Paleozoic Cordilleran Craton Appalachian Late Paleozoic Early Paleozoic • Major Events of North America • Sauk Sequence • Tippecanoe Sequence • Taconic Orogeny

7. Paleozoic PaleogeographyGlobal History • Late Cambrian • H2O circulated freely • Polar regions ice free • Epeiric seas • Laurentia, Baltica, Siberia, Kazakhstania, China • Major highlands • Gondwana, Siberia • Late Ordovician • Gondwana moved southward and across the South Pole • Tillites in Sahara Desert • Late Silurian • Laurentia developed active convergent boundary in eastern margin • Baltica moved NW and collided with Laurentia

8. Paleozoic – Late Cambrian Sauk Sequence • First major transgression • Most of N.A. covered by epeiric seas • N.A. along equator • Evidence of shallow-water deposition • well-sorted, clean sands (ancient shoreline) • Carbonates (stromatolites & ooids)

9. Paleozoic – Late Cambrian Sauk Sequence • Grand Canyon • Good example of Sauk Sequence • Transgression – “fining upwards” • Tapeats Sandstone • Bright Angel Shale • Mauv Limestone • Time transgressive

10. Paleozoic – Late OrdovicianTippecanoe Sequence • N.A. in tropical environment • Sauk Sea regressed • Produced unconformity • Boundary between Sauk and Tippecanoe Sequences • Limestone and dolostone experienced rapid erosion • Major transgression • St. Peter SS at base of sequence • Followed by widespread reefs and evaporites • Carbonates Carbonate--corals, bryzoans, dolostone--reefs/evaporites

11. Paleozoic – Late OrdovicianTippecanoe Sequence • Modern reef structure • Tippecanoe famous for basin rimmed by reefs and evaporites (?) • 30º N&S of equator • Warm, shallow H2O • No sedimentation input • Normal salinity • Evaporites • Evaporation > precipitation • High salinity • Michigan Basin

12. Paleozoic – Late OrdovicianMichigan Basin • Contradiction • Pinnacle reef • Evaporites • Possible Explanation • Rimmed coral basin • Periodically flooded • Pinnacle reef grew upwards in response to rising sea level • evaporation • Evaporite formation

13. Paleozoic – Late SilurianAppalachian Mobile Belt • During L. Cambrian & L. Ordovician (Sauk and Tippecanoe Sequences) • Broad, passive margin along eastern edge of Laurentia • Deposition of carbonates overlying shallow-marine seds.

14. Paleozoic – Late SilurianAppalachian Mobile Belt • Taconic Orogeny • Widening of Iapetus Ocean along divergent boundary • Baltica collided with Laurentia • Iapetus plate subducted beneath Laurentia • Passive  active margin • Results in arc volcanism (mountain-building) • Birth of Appalachian Mts

15. Late Silurian

16. Passive margin, L. Proterozoic-L.Ordovician Mid Ordovician Orogeny

17. Silurian