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Paleozoic 3: Alabama in the Paleozoic

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Paleozoic 3: Alabama in the Paleozoic UNIVERSITY OF SOUTH ALABAMA GY 112: Earth History Paleozoic 3: Alabama in the Paleozoic Instructor: Dr. Douglas W. Haywick Last Time The Paleozoic Part 2 1) Back to Newfoundland 2) Eastern Laurentian Orogenies (Appalachians) 3) Other Laurentian Orogenies (Antler, Ouachita) (web notes 25) Laurentia (Paleozoic North America) Even though this coastline of Laurentia was a passive continental margin, a plate tectonic boundary was rapidly approaching… A B A B Laurentia (Paleozoic North America) The resulting Taconic Orogeny first depressed the seafloor Laurentia (localized transgression) and A Island arc then pushed previously deposited passive continental B margin sediments up into thrust fault mountains. Baltica There was only minimal metamorphism and igneous A intrusions. B Middle Ordovician Laurentia (Paleozoic North America) Laurentia Baltica Middle Ordovician Laurentia (Paleozoic North America) Laurentia Baltica Middle Ordovician Laurentia (Paleozoic North America) The next tectonic event (the Acadian Orogeny) was caused Laurentia by the approach of Baltica A B Baltica A B Baltica Baltica Late Ordovician Laurentia (Paleozoic North America) The Acadian Orogeny was more extensive and more intense (metamorphism and A lots of igneous intrusions) B A B Early Devonian Laurentia (Paleozoic North America) The Acadian Orogeny was more extensive and more intense (metamorphism and lots of igneous intrusions) Early Devonian Laurentia (Paleozoic North America) Lastly, along comes Gondwanna and…. …well you get the idea. A B B A B Mississippian Laurentia (Paleozoic North America) Lastly, along comes Gondwanna and…. …well you get the idea. A B B A B Pennsylvannian Suture zone Laurentia (Paleozoic North America) Lastly, along comes Gondwanna and…. …well you get the idea. B Pennsylvanian Today’s Agenda The Paleozoic Part 3 1) Other Paleozoic Orogenies 2) Alabama in the Paleozoic (web notes 26) Other Laurentian Orogenies Period North America Permian Alleghenian Orogeny* (SE) Pensylvannian Mississippian Ouachita Orogeny (S) Devonian Acadian Orogeny* (E) Antler Orogeny (W) Silurian Ordovician Taconic Orogeny* (NE) Cambrian Other Laurentian Orogenies Period North America Permian Alleghenian Orogeny* (SE) Pensylvannian Mississippian Ouachita Orogeny (S) Devonian Acadian Orogeny* (E) Antler Orogeny (W) Silurian Ordovician Taconic Orogeny* (NE) Cambrian Antler Orogeny Other Laurentian Orogenies Period North America Permian Alleghenian Orogeny* (SE) Pensylvannian Mississippian Ouachita Orogeny (S) Devonian Acadian Orogeny* (E) Antler Orogeny (W) Silurian Ordovician Taconic Orogeny* (NE) Cambrian Other Laurentian Orogenies Period North America Permian Alleghenian Orogeny* (SE) Pensylvannian Mississippian Ouachita Orogeny (S) Devonian Acadian Orogeny* (E) Antler Orogeny (W) Silurian Ordovician Taconic Orogeny* (NE) Cambrian Other Laurentian Orogenies Period North America Permian Alleghenian Orogeny* (SE) Pensylvannian Mississippian Ouachita Orogeny (S) Devonian Acadian Orogeny* (E) Antler Orogeny (W) Silurian Ordovician Taconic Orogeny* (NE) Cambrian Ouachita Orogeny The Appalachians Period North America Permian Alleghenian Orogeny* (SE) Pensylvannian Mississippian Ouachita Orogeny (S) Devonian Acadian Orogeny* (E) Antler Orogeny (W) Silurian Ordovician Taconic Orogeny* (NE) Cambrian Appalachian Provinces 4 Tectonic provinces are identified 1) Plateaus (undeformed) 2) Valley and ridge (folded/faulted) 3) Piedmont (Highly metamorphosed) 4) Blue Ridge (igneous intrusions) Appalachian Provinces We only see the first 3 in Alabama 1) Plateaus (undeformed) 2) Valley and ridge (folded/faulted) 3) Piedmont (Highly metamorphosed) Appalachian Provinces We only see the first 3 in Alabama 1) Plateaus (undeformed) 2) Valley and ridge (folded/faulted) 3) Piedmont (Highly metamorphosed) Appalachian Provinces Alabama Stratigraphy (Paleozoic) Alabama (Early Paleozoic) B Cambro-Ordovician Alabama (Mississippian) B Alabama (Pennsylvanian ) Today’s Homework 1. Time Chart 2 due Thursday (Hadean to end of Proterozoic) Next Time 1) Quiz 10: Multiple Choice 2) Evolution of Plants GY 112: Earth History Lectures 26: Alabama in the Paleozoic Instructor: Dr. Doug Haywick [email protected] This is a free open access lecture, but not for commercial purposes. For personal use only. .
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