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Hydrology and Geomorphic Evolution of Basaltic Landscapes, High Cascades, OR

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Hydrology and GeomorphicPresenter: Anne Jefferson
Length: 2 Parts, 42 min 37 s

View: Part 1 | Part 2 | Part 3

       Topics:

       Part 1

  • Hydrology and Geomorphic Evolution of Basaltic Landscapes - High Cascades - Oregon Geology
  • Influences hydrology?
  • Some ways it might
  • More ways
  • Cascades Geology and Streamflow Patterns
  • Geologic Setting
  • Western Cascades
  • Subsurface storm flow
  • Flows
  • High Cascades
  • Groundwater flow
  • High Cascade springs
  • Geology predicts summer streamflow
  • August flow from springs
  • March flow from springs
  • Volcanic history and flow patterns
  • Study area
  • Flowpaths do not follow topography
  • Stable Isotopes
  • Springs recharge in young lavas
  • Recharge Areas
  • Geology trumps topography
  • Upper McKenzie Springs
  • Remainder of recharge
  • Flowpaths and ages
  • Shallow flowpaths

       Part 2

  • How old is the water?
  • Ages ranges from 3 to 14 years
  • Aquifer volume
  • Cracks in volcanic rock
  • Aquifer Thickness
  • Groundwater velocity
  • Hydraulic conductivity
  • Groundwater flowpaths and geologic history
  • Hydrogeologic controls
  • Motivation: Warming winters
  • Study watersheds
  • Santiam Junction precipitation
  • Clear Lake Water Budget
  • Temporal centroid
  • Autumn Minimum Discharge

       Part 3

  • Sensitivity to climate variability
  • Drainage development
  • Landscape evolution
  • Models of drainage evolution
  • Depression linkage
  • Groundwater seepage erosion
  • Knickpoint migration
  • Permeability reduction
  • Chronosequence of landscapes
  • Drainage density increases over time
  • Chronosequence of landscapes
  • Major springs persist for =1 Ma
  • Chronosequence of landscapes
  • Topographic form - endmembers
  • Topographic form - intermediates
  • Processes that reduce permeability
  • Drainage development on permeable landscapes