Late Paleozoic earth history Flashcards
Define a Clastic wedge
accumulation of mostly detrital sediments deposited next to uplift areas
Where is the Queenstone Delta wedge thickest and thinnest
sediments are thickest and coarsest near the Taconic Highlands and thin away from them.
When did majority of the glacial cycles occur
Over the Gondwana during the late Mississippian and Early Permian
What was happening during the Late Paleozoic Evolution of North America
There were period of:
- extensive shallow marine carbonate deposition
-large coal forming swamps
-Dry, evaporate forming terrestrial conditions
what were the late Paleozoic Sea level changes caused by
- Glaciers on Gondwana
-Tectonism from Pangaea assemblage
What is the Kaskaskia Sequence
Started accumulating as the Kaskaskia Sea transgressed over a flat North American craton during the middle Devonian and late Mississippian
What is the Kaskaskia Sequence made up of
Rock from the eroding highlands of the Appalachian mobile belt
How were Reefs developed in western canada
middle and late Devonian reefs formed as the Kaskaskia sea transgressed
what happened when the reefs grew and restricted the flow of sea water by the end of the middle Devonian
- extensive evaporite deposits formed
-more than 50% of the worlds Potash comes from them
What replaced carbonate-evaporite depositions in part of North America
Deposition of shales
When did the deposition of Black Shales happen
Started mid to late Devonian and at the end of the Devonian there was widespread black shale formation
What is an example of Black shale outcrop
The new Albany Shale
