Geology 9

  1. Aquitard
    An impermeable layer that hinders or prevents water movement.
  2. Aquifer:
    Permeable rock strata or sediment that transmits groundwaterfreely.
  3. Specific yield:
    Moves under the influence of gravity
  4. Specific retention:
    Portion retained as a film on particle and rock surfaces andtiny openings
  5. Permeability:
    the ability of a material to transmit a fluid´╗┐
  6. Porosity:
    percentage of total volume of rock or sediment that consists of pore spaces
  7. Factors that are important to groundwater movement:
    • Porosity
    • Permeability
  8. Gaining streams:
    Gain water from the inflow of groundwater through the streambed
  9. Losing streams:
    lose water to the groundwater system by outflow through the streambed
  10. Where do the highest velocities occur?
    The center just below the surface
  11. Velocity:
    distance journeyed/time
  12. Factors that determine velocity:
    • 1.Gradient, or slope
    • 2.Channel characteristics including shape, size, and roughness
    • 3.Discharge – the volume of water moving past a given point in a certain amount of
    • time
  13. Factors that increase downstream:
    • •Velocity
    • •Discharge
    • •Channel size
  14. Factors that decrease downstream:
    • •Gradient
    • •Channel roughness
  15. Important stream zones based on dominant process:
    • 1.Erosion
    • 2.Sediment transport
    • 3.Sediment deposition
  16. Types of load:
    • •Dissolved load
    • •Suspended load
    • •Bed load
  17. Capacity:
    The maximum load a stream can transport
  18. Bedload transport:
    Particles that make up the bed load move along the bottom
  19. Stream channels:
    • 1.Bedrock channels
    • 2.Alluvial channels
  20. Bedrock channels:
    Streams actively cutting into solid rock
  21. Alluvial channels:
    • •Meandering streams
    • •Braided streams
  22. Facts about meandering streams
    • •Migrates laterally and down valley
    • •Mostly fine-grained particles
    • •Deep, smooth channel
    • •Can form many Oxbow Lakes
  23. Braided streams:
    • •Sand-, gravel-, and boulder-sized particles
    • •Intermittent flow (seasonal)
    • •Channels are shallow and narrow
    • •Islands
  24. Depositional landforms:
    • Deltas
    • Natural levees
    • Alluvial fans
  25. Where do Alluvial fans develop?
    where a high-gradient mountainous stream leaves a narrow valley
Card Set
Geology 9