What are important factors in determining how a river system behaves.

Fluvial geomorphology and dynamics:

• valley cross section forms and the importance of mass wasting to fluvial systems.the need to bend:
• low sinuosity multichannel systems (braided) vs. high sinuousity single channel systems.
• terraces and cut and fill cycles.
• parts: meanders, cutbank, point bar, levees, flood plain, ox bow lakes, terraces.
• dynamics: cut and fill cycles, cutoffs, meander migration, flood deposition
• Elkhorn river near Scribner, Nebraska

Fluvial sedimentology (thinking about the sediments affected by rivers):

• transport mechanisms - bed, suspended and dissolved load.
• alluvium.
• the process of sorting by grain size.
• proximal to distal to sedimentary source:
• coarse to fine grain size overall.
  • rounding of grains.
  • compositional maturity
  • not simple; e.g. glacial tills as source in eastern Nebraska
• channel conglomerates.
• point bar sands.
• flood plain silts and muds.
• fining upwards trend in channel migration sequence.

Drainage networks, a larger perspective:

• various patterns: dendritic vs. trellis.
• evolution of a drainage network and downcutting vs. headward retreat.
• knickpoint migration.
• Nebraska drainages.
  • Lower Niobrara.
  • Niobrara just E of Valentine.
  • Broken Bow.
  • Dismal River.

Lacustrine systems (lakes):

• How do they form geologically; i.e. what are natural damming mechanisms or how are depressions created?
• Lake Diffendal in Nebraska.
• As sedimentary basins: e.g. Lake Gosuite, stratification and oil shales.
• Glacial lakes and breakout floods.

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