Sedimentary Geology Geos 240

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Sedimentary GeologyGeos 240 Chapter
8Depositional EnvironmentsPart 1Introduction,
Fluvial Coastal

• Dr. Tark Hamilton
• Readings from Sediments Basins (81-67)
• Camosun College

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Great Barrier Back Reef, Queensland
Branching Corals Carbonate Sand
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Depositional Environments
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The Peace River, Ft. St. John, NE B.C.
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Four
Decreasing Gradient 1gt2gt3gt4
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3
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Gravel-Sand-Silt-Clay
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Sandy Braided River ModelBased on South
Saskatchewan
Bars Persist for decades
Flow Aggradation
Lateral Aggradation
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Anastomosed River ModelBased on Cumberland
Marshes,East Central Saskatchewan-Manitoba
Stable Vegetated Marsh
Flow Direction, Channel Sands
Crevasse Splay Deposit
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Cutbank, Upwards Fining, Cenozoic
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Narrow Sand Body, Permian Anastomosed River, NM
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Point Bar Sand with Lateral Accretion Mud Fill
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Cutbank, Arid Fluvial Sys. AZ
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Cutbank, Arid Fluvial Sys. AZ
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Cutbank, Carboniferous Channel Sand, KY
Collapsed Rotated Block Of Sandstone that
fell Into the Channel
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Cutbank, Sand on Sand, Jurassic AZ
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Box Canyon Cut into Basal Triassic Unconformity AZ
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Box Canyon Cut into Basal Triassic Unconformity AZ
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Caliche Paleosol, Triassic Redbeds, Spain
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Caliche Paleosol, Triassic Redbeds, Spain
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Interbedded Floodplain Siltstones Musdtones
w/Channel
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Thin Floodplain Muds over Sheet Sand, Devonian,
Arctic Canada
Upwards Fining
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Modern Ergs Eolian DesertsTropic of Cancer
Capricorn 25N S (Why Here?)Continental
Interiors Rainshadows (Find 2)
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Facies Model for an Erg (Desert)
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Cyclic Stratigraphy of Dunes
Climate, Sea Level, WT Change
MBS Deflation, Lags, Ventifacts, Desert Varnish,
Blow Outs, Downlap
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Stream (WT) Cutting Dunes, Colorado
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Interdune Pond Mudcracks w/Silt, Gobi
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Slumped Bed on Face of Dune, Navajo Sandstone,
Arizona
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The Barchan Dune that ate the Truck, Gobi
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Deflation Surface Ventifacts w/Desert Varnish Gobi
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Deflation Surface Comet Marks Sand in Lee, Gobi
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The Ventifact Wind Faceted Stone
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Deflation Surface w/Ventifacts, Triassic Spain
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Deflation Surface w/Ventifacts, Permian Scotland
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Lacustrine Deposits
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Lacustrine Oil Shales Green River Fm, Eocene WY
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Varved Glacio-lacustrine Clay/Silt, Pleistocene,
ON
Dropstone (see notes)
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Hypothetical Coastal Depositional System Facies
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South Carolina Barrier Islands Spit Bars, Tide
Flats
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South Carolina Barrier Islands Estuary
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Galveston Island Matagordia Bay, Texas
What are the green curves?
What is this feature?
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Dune Beach, South Padre Island (Galveston,
Texas)
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Turbulent Dispersion of Shelf Mudsafter
Hurricane Ida MODIS 10/10/09
Shelf
Idas Path
See Notes
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The End of Part 1!