Groundwater Flashcards
Unconfined aquifer
Aquifer that is exposed at groundwater surface and has for its upper boundary, the water table
Confined aquifer
Aquifer unit that is overlain by an “impermeable layer” or “aquitard”and is not directly exposed at ground surface
Semi-confined/leaky aquifer
An aquifer bounded by aquitards that are semi-permeable and can permit a significant amount of groundwater to flow into or our of the aquifer
What is a perched water table?
Local groundwater accumulation that is isolated above (or “perched” the larger regional (or “main”) groundwater table
Saturation
The fraction of the pore volume filled with each fluid
Hydrostatic/hydrulic head
The head is the height of the above the measurement point in length (L) units
Pressure
The fore per unit area applied on a surface by a fluid
Permeability
The measure of the flow capacity of the porous medium to fluids
Recharge zone
In upland areas, precipitation infiltrates through the unsaturated zone and enters the saturated zone across the water table. Downward component of vertical flow
Discharge zone
occurs in lowland areas, water table intercepts the ground surface and groundwater discharge will occur, spring may form, upwards component of groundwater flow exists
Point source
Small, concentrated
Non-point source
Large, diffuse
