The three types of work done by streams
- Erosion
- Transportation
- Deposition
Ease of transport sand vs clay/silt in water
Sand is easier to transport as it is less cohesive and larger
What the Hjulström-Sundborg Diagram demonstrates
critical sediment sizes for transport in certain stream velocities
How imbrication affects erosion
Can protect sand underneath rocks
Stream power definition (not equation)
the amount of energy that water in a river is
exerting on the
sides and bottom of the river
Changes as you move downstream
Stream power equation
Location of highest flow speed in a straight portion of a river
Center top
Stream gauges
Indicate or measure height of water level, the "stage"
Hydrograph
Water level graph
Effect of steep slopes on a hydrograph
Quick formation of high peaks
Effect of gentle slopes on a hydrograph
Slower formation of small peak
Effect of urbanization on a hydrograph
Quick formation of high peaks due to increased overland flow
Scale of x axis on a flood frequency analysis
Logarithmic
FLUID PROPERTIES
influence how they can erode and transport sediments and whether flow is laminar or turbulent
Density and how it affects sediment transport
weight per mass (influences sediment settling rate)
Viscosity
internal frictional force and measure of resistance to flow
(~thickness of a fluid)
Laminar vs turbulent flow, sediment transportation
Turbulent flow carries more sediment
Reynolds number
dimensionless/unitless parameter used to determine if flow is turbulent or laminar
the ratio of inertial forces to viscous forces
Froude number
dimensionless/unitless parameter used as a measure of free surface resistance used to determine if flow is subcritical or supercritical.
the ratio of inertial forces to gravitational forces
Froude number and river depth pattern
Deep rivers are more likely subcritical than shallow rivers, the faster the stream flows the more likely it is supercritical
TIDAL BORE
A strong tide that pushes up the river,
against a river current
that flows with SUBCRITICAL FLOW
hydraulic jump
sudden transitions from laminar to turbulent flow