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Primary-syn sedimentation (e.g. bedforms)
econd r - ost sediment tion e
bioturbation)
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Flute casts
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Groove casts
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Eolian deflation surface, Mars (just kidding, its Argentina)
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Mucracks, Salinas Grande, northern Argentina
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Mudcracks in Jurassic strata southern Utah
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Flame structures, Paleocene, Pt. Lobos, CA
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Miocene gas escape structures, Sta. Rosalia, Baja
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Cretaceous marine deposits, dinosaur track or gutter casts? NW
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Biogenic structures: Stromatolites
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-Continental (alluvial, fluvial, eolian,transitional)-Marine
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I. Depositional System= consists of associated sedimentaryenvironments
Facies= a group or related items
Lithofacies= a group or related rocks of a particular
lithology
Facies Model= a general summary of a particular
distribution of facies in many modern and ancientexamples.
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II. Alluvial Fan
characterized by:Radial geometry oca on nex o e moun a n ronGravity flows (debris flows) in the proximal part
Channels gets smaller downstream
The process by which alluvial fan deposit great amount of
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Salt Creek fan, California
uv a rom a n o was aga ns vs. uv a a n r ver
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Side-valley alluvial fan, St. Elias Mtns., Yukon Territory
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, -
SSW. Note dendritic pattern across fan surface. Roadencircling fan provides scale.
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Walther's Law = sedimentary environments foundadjacent to each other at one time will be found in
major unconformities (i.e. time missing) exists
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