Streams Flashcards
How does running water form?
Begins as sheetflow
Sheetflow develops into tiny channels (rills)
Rills develop into streamflow
What are the types of streamflow?
Laminar flow
Turbulent flow
What is laminar flow?
Streamlines are parallel (slow)
What is turbulent flow?
Streamlines intertwine, complex mixing (fast)
What factors determine velocity?
Gradient
Channel characteristics
Discharge
What is channel discharge?
Total volume of water in stream moving past particular point in given period of time
What factors increase downstream?
Velocity
Discharge
Channel size
What factors decrease downstream?
Gradient
Channel roughness
What is competence?
Maximum-sized particles streams can carry, determined by velocity
What is capacity?
Total load stream can carry, function of discharge
What are the types of sediment deposits?
Channel deposits
Floodplain deposits
Alluvial fans
Deltas
What are channel deposits?
Bars
Braided streams
Deltas
What are floodplain deposits?
Natural levees
What are alluvial fans?
Develop where a high-gradient stream leaves narrow valley and then flattens out
What are deltas?
Forms when stream enters an ocean or lake
