Paleozoic 2: Laurentian Orogenies - University of South Alabama
Transcript of Paleozoic 2: Laurentian Orogenies - University of South Alabama
![Page 1: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/1.jpg)
Quiz Nine (9:30-9:35 AM)
![Page 2: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/2.jpg)
GY 112: Earth History
Lecture 25: Paleozoic 2: More Laurentia!
Instructor: Dr. Douglas W. Haywick
UNIVERSITY OF SOUTH ALABAMA
![Page 3: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/3.jpg)
Last Time
The Paleozoic of North America
1) Laurentian passive continental margin sedimentation
2) Central North America 3) The Grand Canyon (geology)
(web notes 24)
![Page 4: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/4.jpg)
Laurentia (Paleozoic North America)
Consider: 1) passive continental margin 2) shallow marine water (shelf) 3) tropical climate All the way from Labrador to Alabama 1+2+3= Fossil. Limestone, oolite, quartz arenite etc.
Equator:
![Page 5: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/5.jpg)
Laurentia (Paleozoic North America)
The Humber zone is a region of undeformed, passive continental margin rocks
http://iz.carnegiemnh.org/crayfish/country_pages/newfoundland.htm
![Page 6: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/6.jpg)
Laurentia (Paleozoic North America)
Classic Paleozoic reef rocks (stromatolites, rugose and tabulate corals), quartz arenite sandstone, shallow marine dolostone, even some evaporites
![Page 7: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/7.jpg)
Laurentia (Paleozoic North America)
A sudden (localized) deepening occurred (transgression) and above that….
![Page 8: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/8.jpg)
Laurentia (Paleozoic North America)
Thrust faulting…
A
B
A
B
Thrust Faulting
![Page 9: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/9.jpg)
Cratonic Sequences
Middle Ordovician Early Devonian
Ignoring tectonics for a moment and you’ll see that sea water covers much of the craton in these 2 paleogeographic images, but not always to the same extent…
![Page 10: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/10.jpg)
Cratonic Sequences
When continents flood during transgressions, sediment is deposited. When regressions occur, erosion takes place producing unconformities (disconformities) Thick sedimentary packages between disconformities are called cratonic (depositional) sequences.
![Page 11: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/11.jpg)
Cratonic Sequences
When continents flood during transgressions, sediment is deposited. When regressions occur, erosion takes place producing unconformities (disconformities) Thick sedimentary packages between disconformities are called cratonic (depositional sequences). •Basins have thick sequences (shorter disconformities)
•Arches/domes have thin sequences (longer disconformities)
![Page 12: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/12.jpg)
Cratonic Sequences
![Page 13: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/13.jpg)
Today’s Agenda
The Paleozoic Part 2
1) Back to Newfoundland 2) Eastern Laurentian Orogenies (Appalachians) 3) Other Laurentian Orogenies (Antler, Ouachita)
(web notes 25)
![Page 14: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/14.jpg)
Laurentia (Paleozoic North America)
The Humber zone is a region of undeformed, passive continental margin rocks
http://iz.carnegiemnh.org/crayfish/country_pages/newfoundland.htm
![Page 15: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/15.jpg)
Laurentia (Paleozoic North America)
Thrust faulting…
![Page 16: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/16.jpg)
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
![Page 17: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/17.jpg)
Laurentia (Paleozoic North America)
Middle Ordovician
Laurentia
Baltica
Island arc A
B
A
B
The resulting Taconic Orogeny first depressed the seafloor (localized transgression) and then pushed previously deposited passive continental margin sediments up into thrust fault mountains. There was only minimal metamorphism and igneous intrusions.
![Page 18: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/18.jpg)
Laurentia (Paleozoic North America)
Laurentia
Baltica
Middle Ordovician
![Page 19: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/19.jpg)
Laurentia (Paleozoic North America)
Laurentia
Baltica
Middle Ordovician
![Page 20: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/20.jpg)
Laurentia (Paleozoic North America)
Late Ordovician
Laurentia
Baltica
A
B
A
B
The next tectonic event (the Acadian Orogeny) was caused by the approach of Baltica
Baltica
Baltica
![Page 21: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/21.jpg)
Laurentia (Paleozoic North America)
Early Devonian
A
B
The Acadian Orogeny was more extensive and more intense (metamorphism and lots of igneous intrusions)
A
B
![Page 22: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/22.jpg)
Laurentia (Paleozoic North America)
Early Devonian
The Acadian Orogeny was more extensive and more intense (metamorphism and lots of igneous intrusions)
![Page 23: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/23.jpg)
Laurentia (Paleozoic North America)
Mississippian
B
Lastly, along comes Gondwanna and…. …well you get the idea. A
B A
B
![Page 24: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/24.jpg)
Laurentia (Paleozoic North America)
Pennsylvannian
B
Lastly, along comes Gondwanna and…. …well you get the idea. A
B A
B
Suture zone
![Page 25: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/25.jpg)
Laurentia (Paleozoic North America)
Pennsylvanian
B
Lastly, along comes Gondwanna and…. …well you get the idea.
![Page 26: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/26.jpg)
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
![Page 27: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/27.jpg)
Other Laurentian Orogenies
Antler Orogeny
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
![Page 28: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/28.jpg)
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
![Page 29: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/29.jpg)
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
![Page 30: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/30.jpg)
Other Laurentian Orogenies
Ouachita Orogeny
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
![Page 31: Paleozoic 2: Laurentian Orogenies - University of South Alabama](https://reader036.fdocuments.net/reader036/viewer/2022081622/613d1e04736caf36b759844b/html5/thumbnails/31.jpg)
Today’s Homework 1. Catch up on your sleep!
Next Time 1. Paleozoic Geology of Alabama