Lecture 8 Flashcards
What creates meandering rivers?
The undertow spiral water pattern that pulls down on the outer bank of a river eroding that side
What does the term tortuos refer to?
A river working back in on its self
What is an oxbow lake?
A cut off meander
What is a scroll bar?
The ridges formed by multiple point bars
What is a point bar?
The build up of sediment at a rivers inner edge
What is a braided river and what causes it?
It is a river with multiple channels cause by a steep slope and high discharge and sediment loads
What is a alluvial fan?
Terrestrial feature where a steep stream leaves a narrow valley
What is a delta?
A subaqueous feature where a stream enters an ocean or lake
What four things can humans effect in a river system?
Amount of discharge and sediment
Flow
Slope and base level
Land use
True or false
It is impossible for a river to remain straight.
True
What are the four sources of river flow?
Base flow: provided by ground water
Stage and volume
Interflow: seepage above ground water table
Direct precipitation
What is a hydrograph?
A plot of discharge over time
Can a groundwater table change in depth?
Yes due to lack of or surplus of water
How does urbanization impact river flow?
Creates a less permeable ground surface leading to more run off
What causes flooding?
When discharge exceeds the stage height
Name the four types of floods.
Regional
Flash
Ice jam
Dam failure
What causes a regional flood?
High precipitation in the area or rain-on-snow events
What causes flash floods?
High precipitation in the mountains arid or urban landscapes