Chapter 13: Groundwater Flashcards
Groundwater
Water in the saturated zone
Water Table
Boundary between Zone of Aeration and Zone of Saturation
- Roughly parallel to the ground surface, connects to surface
- Connects to surface water (base flow, humid climate)
- Water table slope causes groundwater flow
- Downward flow under recharge area
- Upward flow under discharge areas
Zone of Aeration
Unsaturation
- Infiltration occurs here
- infiltration water is recharge
Zone of Saturation
Groundwater flow
Groundwater Flow Rate
Darcy's Law -V=K x Sn K= Permeability S= hydrolic gradient= H(head or height)/L(horizontal distance) n= porosity
Porosity
Proportion of pore space in rock/sediment
Permeability
Capacity to transmit fluid
-pore connections
Aquifer
A body of rock/sediment that yields a useful quantity of water to a well
- Saturated
- High permeability
- High porosity
Unconfined/Surface Aquifer
Water table
- Gravel and sand, sand and gravel
- Cone of Depression
Cone of Depression
lowered water table due to pumping (mining of ground water)
Confined/ Bedrock Aquifer
Sandstone, fractured limestone (carbonate)
-Fractured Carbonate becomes cavernous
-Sinkholes and Karst topography forms
Confined by aquicludes (practically impermeable rock) above and below: dense (unfractured) carbonate, shale, and granite
-Pressure surface
-Artesian Conditions
Pressure Surface
Level to which water rises
Artesian Conditions
rises above top of aquifer
Water Supply
renewable resources; 2/3 of peeps in WI drink groundwater, 86% of US drink surface water
Water Quality
Susceptibility of groundwater to contamination determined by:
- type of bedrock
- depth of bedrock
- depth to water table
- soil characteristics
- Characteristics of surficial deposits
