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Sedimentology and Stratigraphy (Ch3 (Grain Size Analysis (Positively…

- - - - ratio of intertial forces to viscous forces
    - - Boundary Layer
      - Viscous sublayer
    - - Flow Regime
      - Fr > can't move upstream Fr < can move upstream Fr = 1 is boundray between tranquil flow and shooting flow
        
        ex) sink flow water
  - - - Bedload Transport
        
        Saltation: Type of bedload transport, sand-sized sed moves in intermittent contact with the bed
        
        Uniterrupted:
        
        Interrupted: hits another grain mid hop
        
        Traction: Rolling, Sliding, Impact and Creep
      - Suspended Load Transport
        
        Intermittent suspension: collisions high in the water collumn
        
        Continuous suspension: carried along at almost the velocity as the fluid flow
        
        Wash Load: fine, clay-sized particles with very low settling velocities, travels at about the same velocity as the water, transported rapidly through river systems
    - - Hjulstrom Diagram
        
        Grey area represents threshold velocities for entrainment under ideal circumstances
        
        A more realistic version
      - Bernoulli Effect: Pressure increases on top so pressure must decrease on the underside, creating Lift Component
      - Entrainment happens when Fluid Force > gravity + Friction
    - - Dust load...like wash load only smaller
    - - Sediment gravity flow
        
        Slides
        
        Rock Flow
        
        Turbidity Current
        
        Turbulent Fluid: enough fluid to not have grains touch
        
        Liquefied Flow
        
        Newtonian fluid: upward escape of intergranular fluid, high viscosity ex. quick sand-creates fluid escape structures
        
        Grain Flow
        
        Non-Newtonian fluid: grain interaction (dispersive pressure) : grains knock into one another
        
        Bouma Sequence: ideal turbidite sequence
- - - - Phi scale
      - Gravel, Sand, Silt, Clay
      - Very Coarse Sand,
        Coarse Sand,
        Medium Sand,
        Fine Sand,
        Very Fine Sand,
  - - - Form: Equant --> Platy
      - Rounded / Angularity:
        Decreasing roundness or increasing angularity
      - Surface Textures: Pitted --> Smooth
  - - - Matrix Supported:
        
        Grain Supported:
        
        Tangential Contact
        
        Sutured Contact
        
        Concavo-convex Contact
        
        Long Contact
- - - - Very Thick Bed, Thick Bed, Medium Bed, Thin Bed, Very Thin Bed, Lamina, (Thick Lamina,Thin Lamina)
      - Planar bed
        
        Laminated bedding:
        
        Graded Bedding: coarse to fine, way up indicator
        
        Massive Bedding: Structureless
    - - Ripples!
        
        Climbing Ripples: alpha>beta=climbs, alpha<beta=cross bedding
      - Cross Bedding #
      - Lenticular bedding:
        
        Wavy Bedding: 50/50 sand/mud
        
        Lenticular Bedding: Sand in Mud matrix
        
        Flaser bedding: mostly sand
- - - - Undulatory Extinction when viewed in thin section and turned
    - - Syntaxial Overgrowth
    - - QFL Ternary Diagrams
        
        Gilbert Classification System for Sandstones
        
        Percent Matrix
        --> Maturity Scale
        --> less matrix means less clay
        
        Removal of Clay, 2. Sorting of non-clay portion, 3. Rounding of Grains
      - Conglomerates
        
        Matrix supported
        
        Diamictites: poorly sorted Glacial deposites
        
        Clast/grain supported
        
        Oligomict: single clast comp
        
        Polymict: assortment of clast types
        
        Petromict: clasts unstable and weathered quickly
      - Mudstones
        
        Indurated v. non-indurated
        
        Laminated v. non laminated