Ch 9

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• Ch 9 10 Early Paleozoic
• Cambrian
• Tectonics
• Land shape
• Rock formation
• Evolution of life
• Paleoclimate
• Early Ordovician
• Tectonics
• Land shape
• Rock formation
• Evolution of life
• Paleoclimate

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• Cambrian
• Metazoans - 600 mya

Movie http//www.pbs.org/wgbh/evolution/library/0
3/4/l_034_02.html
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Fig. 9.13
Early Cambrian Scale bars are 1 mm
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Fig. 9.14
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Fig. 9.16a
Trilobite
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Fig. 9.17

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Burgess Shale soft bodied organisms
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Fig. 9.22a
Time Line
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Position of continental plates in Cryptozoic and
Cambrian
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Fig. 10.23
Current continental margin Glauconite
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Oolites 1-2 mm from submarine dunes of present
Bahama Bank
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Restoration from California to Utah
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• Continental shelf deposition
• Craton deposition

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Fig. 10.6b
Carbonate over shale over sandstone Death Valley,
California
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Fig. 10.6d
Wind blown sand dunes, Dells, Wisconsin
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Fig. 10.7
Thickness of Cambrian rock
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Fig. 10.8
Cambrian sedimentary facies
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Fig. 10.9
Paleogeographic Interpretation Epeiric sea Sauk
Transgression
Iapetus Ocean
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Well rounded quartz sand grains Glauconite
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Fig. 10.17
Present sand dunes of Little Bahama Banks 1-2 m
under water
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• Carbonates
• Clastic limestone
• Evaporites

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Stromatolites, New York, indicate that Sauk Sea
less than several 10 ms deep
Flat pebble conglomerates, Wisconsin, indicate
shallow water disturbance of mud cracks by storm
induced waves
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Fig. 10.25
Effect of hurricanes
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July 2001- sandy beaches and sand flats, low
vegetated sand dunes, and marshes behind barrier
island. August 31, 2005 - two days after
Hurricane Katrina - Storm surge and waves
submerged islands, eroded beaches and marsh.
Chandeleur Island chain, Hurricane Katrina,
2005 (photos from USGS, 2005)
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Course well rounded conglomerate formed in
Baraboo, Wisconsin during Tropical storms
boulders up to 1.5 m diameter
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Hummocky stratification
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Paleoclimate Cambrian Tropical with episodic
storms