Formation of Sedimentary Basins

Subduction

- Trench
- Forearc
- Backarc

Thrust Loading

- Foreland

Crustal Thinning

- Rift Basin

Cooling and Loading

- Passive Margin

?????

- Intracratonic Basins

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Wilson Cycle

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Supercontinent Cycle (500 million years)

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Accretionary Tectonics

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Allochthonous Terrains

• allochthonous
  
• autochtonous
  

Microplate

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Accreted lithospheric plates, western margin on North America, (Figure 14.21, p. 367)

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red - blocks from continents other than N. America
dark green - blocks displaced from parts of N. America

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Example: Rocks of the Wollawa Mountains, Oregon, contain Triassic fossils similar to those in the Swiss Alps.

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Triassic Paleogeography

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Major Structural Provinces

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1) Canadian Shield (Precambrian)
2) Interior Lowlands (Platform)
3) Appalachian Orogenic Belt (Paleozoic)
4) Cordilleran Orogenic Belt (Mesozoic)
5) Coastal Plain (Mesozoic & Cenozoic)

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last updated 2-23-01

All original material copyright (c) 1998 by Annabelle Foos. All rights reserved.