Earth History
GEOL 2110
The Paleozoic Era
Carboniferous and the Permian Periods
in North America
Major Concepts
• Carbonate deposition dominant in the Silurian and
Devonian, persisted into the early Carboniferous (the
Mississippian period).
• After a major regression and subsequent transgression
marking the Mississippian-Pennsylvanian break in North
America, the Absaroka sequence was dominated by
clastic sediments and great accumulations of land-based
organic material creating coal seams.
• This change in sedimentation, which persisted into the
Permian, was triggered by creation of the final orogenic
event of the Appalachian mobile belt caused by the
collision of southeastern North America with Africa and
South America and the creation of the largest continental
land mass ever on Earth - Pangea
Events of the Late Paleozoic Era
Mississippian Deposits
More Limestone
Chockful
O’ Crinoids
Madison LS, MT
Redwall LS, AZ
Pahasapa LS, SD
Late Mississippian Regression
Immature clastic sediment appear in
Eastern NA deposits
Sourced from deeper erosion of
rejuvenated Caledonian and Acadian Mts
More Unconformities developed on warped craton highs
Pennsylvanian Deposits
Clastic Sedimentation Dominates (+Coal)
Pennsylvanian Deposits
Cyclothems – Trangressive Cycles
Limestone - Marine
Sea
Trangression
Coal
Sea
Regression
Land
Trangression
Shale – Lagoon / Floodplain
Sandstone -Delta / Barrier Island
Illinois Basin Cyclothem
TRANSGRESSION
Organic Shale
Forested Marsh/Swamp
Pennsylvanian Deposits
Cyclothems – Trangressive Cycles
Land Transgression
Sea Transgression
Pennsylvanian Deposits
Over 100 Cycles in 100 million years!
Cause of Cycles
-Rapid sea level changes due to
Gondwanaland glaciation
- Spasmodic tectonic up-down oscillations
-Cyclic climate change affecting erosion and
sedimentation
Pennsylvanian Coal Deposits
Subtropical Rain Forests
Peat
Anthracite
Everglades
Bituminous
Coal
Anthracite
Coal
Permian Deposits
Craton Tilts West / Seas Retreat / Climate Dries
Barrier Reefs in the Southwest
Ancestral Rocky Mountain
Pennsylvanian-Permian Uplift
Late Paleozoic Strata of the Grand Canyon
Kls
Tf
Css
HSh
Sgp
Late Paleozoic Strata of the Sedona Area
Permian Climate Dries
In the Rain Shadow of the Appalachians
The Appalachian
Orogeny
Creating Pangea ~250 Ma
Continent-Continent Collision
1950’s Interpretation
1980
Monster Thrust Faulting
~260 Km Displacement
Google Earth Tour of the Appalachians
Summary of Paleozoic Tectonics
Acadian/Caledonian
Appalachian/Hercynian
Gondwanaland
Taconian
North American Paleozoic Orogenies
Next Lecture
The Paleozoic Era
Geological History of Gondwanaland and
Late Paleozoic Life
Mid-term on Friday!!
Chapters 8-13