Proterozoic Tectonics Flashcards
1
Q
what are the characteristics of the Proterozoic Eon
A
- Many Proterozoic rocks exposed and not metamorphosed
- fossils are uncommon
- Fewer Greenstone belts and Granite gneiss complexes
- Passive continental margins
- Banded Iron formations
2
Q
what is Laurentia
A
- Early continent that makes up the core of North America
3
Q
Define a Basement Rock
A
Crystalline (igneous and metamorphic) rock that lie beneath sedimentary rock mostly Archean and Proterozoic
4
Q
Define Orogen
A
A part of Earths that was or being deformed during and Orogeny
5
Q
Define Orogeny
A
An mountain building event
6
Q
What is the Wilson Cycle
A
- Uplift
- Divergence (Spreading) water floods
- Divergence (sedimentary rock deposited)
- Convergence (subduction) crust sinks
- Convergence (Collison and uplift)
- Convergence and uplift (hit each other)
7
Q
Where are the Grenville Orogeny located
A
the eastern boundary of Laurentia from 1.0-1.3 Ga
8
Q
What were the Grenville belts a result of
A
the closure of an ocean basin (end of the Wilson cycle)
