Geologic

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Geologic Story of Minnesota (as told by its
rocks)
Part IV Phanerozoic Rocks
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Geologic Timescale
Todays Lecture
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Evolution of the Penokean Mountains
TWIN CITIES
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1,000,000,000 Years Ago Minnesota becomes
the stable interior of the North American
Continent
500,000,000 Years Ago Shallow seas begin to
periodically flood Minnesota
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The Cambrian Explosion of Life
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Snowball Earth The Trigger of the Cambrian
Explosion??
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The Carbon Cycle
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Supercontinent Rodinia 750 Ma
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Paleozoic Epicontinental Seas
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Geography of Middle Laurentia in Paleozoic Time
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Advanced Transgression
Regression
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The Jordan Sandstone Unconformity
Missing Fossils
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Paleozoic Formations of the Midwest
Twin Cities
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Ordovician Rocks of the Mississippi River Bluffs
P-Platteville Limestone G-Glenwood Shale
S-St. Peter Sandstone
P
G--
S
Mound Park
P
Minnehaha Falls
G--
S
P
G--
S
Ford Dam and Lock
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Fossil Hunting in the Twin CitiesLilydale Park
(the Brickyard)
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Paleogeography at the End of the Paleozoic
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Extinctions at the End of the Paleozoic
Snowball Earth?
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Western Interior Seaway
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Cretaceous Deposits in Minnesota
Conglomerate and sandstone on banded iron
formation in north-central Minnesota
Deeply weathered gneiss in Southwestern Minnesota
Lignite and shale in southern Minnesota
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The Coleraine Formation
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Why dont dinosaur fossils occur in Minnesota?
High Sediment Production
Low Sediment Production
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The Break-up of Pangea
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The Bedrock Geology of Minnesota is Complete