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What caused the Physiographic provinces of Georgia?. Georgia’s Physiographic Provinces. Coastal Plain Recent sediments at coast to soft sedimentary to NW Flat-lying strata Age: Recent to Late Mesozoic Piedmont Igneous and metamorphic rocks
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Georgia’s Physiographic Provinces Coastal Plain Recent sediments at coast to soft sedimentary to NW Flat-lying strata Age: Recent to Late Mesozoic Piedmont Igneous and metamorphic rocks Heavily folded and faulted Age: Paleozoic and some Precambrian Blue Ridge Igneous and metamorphic rocks Heavily folded and faulted Age: Paleozoic and some PC Ridge and Valley Sedimentary rocks Gently folded and faulted Age: Paleozoic Appalachian Plateau Same rocks and age Dipping gently to west
Plate thicknesses:Ocean plates = 5 km avg.Continental plates = 100 km avg.
1. 700 – 600 mya: Rifting of Supercontinent Rodinia forms the Iapetus Ocean Precambrian Rodinia igneous and metamorphic rocks brought to surface along western edge of Piedmont through thrust-faulting during Appalachian Mtn. formation.
Cartersville Fault Appalachian Plateau Fall Line Ridge and Valley Blue Ridge / Piedmont Coastal Plain Rifted African Plate Cross Section of Physiographic Provinces
2. 600-400 mya: Iapetus Ocean closing.0ceanic-oceanic convergent boundary forms volcanic Taconic island arc. Taconic orogeny occurs when island arc exotic terrane and flysch accrete to N. America. Thrust faulting, folding, and metamorphism of igneous volcanic rocks. These igneous and metamorphic rocks form the Blue Ridge Province. Western Iapetus
Cartersville Fault Appalachian Plateau Fall Line Ridge and Valley Blue Ridge / Piedmont Coastal Plain Rifted African Plate Cross Section of Physiographic Provinces
3. 400-350 mya: Iapetus closing. Second island arc called Avalon accretes to N. America. Compression, thrusts, metamorphism of flysch and volcanic rocks.
Cartersville Fault Appalachian Plateau Fall Line Ridge and Valley Blue Ridge / Piedmont Coastal Plain Rifted African Plate Cross Section of Physiographic Provinces
4. 300 mya: Eastern Iapetus closes, Pangea forms. Alleghenian orogeny occurs with continental-continental convergent boundary. Folding and thrusting. These igneous and metamorphic rocks form the Piedmont provinceThrust faulting of continental sedimentary rocks forms Ridge and Valley province and Appalachian Plateau.
Cartersville Fault Appalachian Plateau Fall Line Ridge and Valley Blue Ridge / Piedmont Coastal Plain Rifted African Plate Cross Section of Physiographic Provinces
4.250 mya – present: Rifting of Pangea forms the Atlantic Ocean. Normal faulting. Divergent boundary forms. Passive plate margin. Weathering and erosion. Coastal Plain Province and continental shelf composed of late Mesozoic and Cenozoic sediments.
Cartersville Fault Appalachian Plateau Fall Line Ridge and Valley Blue Ridge / Piedmont Coastal Plain Rifted African Plate Cross Section of Physiographic Provinces Taconic terrane Avalon terrane
Georgia’s Physiographic Provinces Coastal Plain Recent sediments at coast to soft sedimentary to NW Flat-lying strata Age: Recent to Late Mesozoic Piedmont Igneous and metamorphic rocks Heavily folded and faulted Age: Paleozoic and some Precambrian Blue Ridge Igneous and metamorphic rocks Heavily folded and faulted Age: Paleozoic and some PC Ridge and Valley Sedimentary rocks Gently folded and faulted Age: Paleozoic Appalachian Plateau Same rocks and age Dipping gently to west