Block 3: Hydrology & Groundwater Flashcards
(15 cards)
For which materials is water a good & bad solvent?
Good solvent for polar organics & inorganic ions
Bad solvent for hydrocarbons & hydrophobic minerals
Define reservoir theory
The theory that the residence time of a single H2O molecule in the ocean is determined by influx & outflow, with residence time = volume/flux
Define groundwater, the water table, & the saturated zone
Groundwater is water within the saturated zone
The saturated zone is the area in which all pores and fractures in soil & rock are fully saturated
The water table is the upper limit of the saturated zone
Give examples of advection on microscales & macroscales
Advection, the movement of matter by physical flows, happens as pore flow & capillary flow on microscales & river flow & runoff on macroscales
Define saturated & unsaturated flows
Saturated flow occurs when pores are completely saturated & unsaturated flow occurs when pores in the wettest soil zones are only partially filled
What does Darcy’s Law solve for?
Flow velocity (distance/time) through a porous medium, which can be converted to discharge (volume/time)
What are catchments (i.e. watersheds or basins)
Areas of land that collect & drain water into a body of water, typically from a higher elevation
How do the measurements discharge & runoff differ?
Discharge measures flow volume relative to time, whereas runoff measures discharge relative to catchment area
When do Hortonian & Dunnian flows occur?
Hortonian flow occurs when rainfall intensity exceeds the soil’s infiltration capacity, creating runoff
Dunnian flow occurs when the water table rises towards the surface so that rainfall creates overland flow
What is translatory flow?
Translatory flow occurs when infiltrating water elevates the water table, pushing groundwater downslope into streams
What is the old water paradox & celerity
During storms, streamwater contains large amounts of ‘old’ water stored in the subsurface as discharge responds to the pressure wave & displaces old water first. Celerity refers to this wave
Where do throughflow & groundwater flow occur?
Throughflow occurs in the unsaturated zone & groundwater flow in the saturated zone
How do conservative & non-conservative transport differ?
In conservative transport species are transported by flow without any chemical reactions, whereas in non-conservative transport species are altered by chemical reactions along the flow pathway
What factors does saturated hydraulic conductivity include?
Porosity, permeability, tortuosity, & water density. These measure the rate at which water flows through a porous material
What are the steps for delineating a watershed?
1.Trace watercourse from source to mouth
2. Outline points of highest elevation (breakpoints)
3. Determine slope direction
4. Outline watershed boundaries
