groundwater 11.3. earth’s water budget from miller’s living in the environment
TRANSCRIPT
Groundwater
11.3
Earth’s water budget
From Miller’s Living in the Environment
Geology of an aquifer
From Miller’s Living in the Environment
Words to know…
• Water table = the top of the layer of water in the ground.
• Confining layer = layers of rock that the water can not pass through…it traps the water
• Spring = where water flows up to the surface of the ground
• Well = man made hole that goes to the water table & water is pumped to surface
Aquifer
• Layer of rock that contains groundwater.• The water sits between the grains of sand or
rock that are connected.• The water can move through the sand or rock
layer.
GW use in USA & China
From Miller’s Living in the Environment
Areas of aquifer depletion
From Miller’s Living in the Environment
Areas of ground subsidence
From Miller’s Living in the Environment
Porosity
• Percentage of open space between particles in the rock.
belmont.sd62.bc.ca
Porosity
• % of open spaces in given volume of rock• Amount of water a rock can hold• Influenced by:– Sorting • poorly sorted = lower porosity
– Packing• tightly packed = lower porosity• Loosely packed = higher porosity
Permeability
• How readily the water passes through the open spaces of the rock.
kalkaskacounty.net
Permeability
• How freely water passes through open spaces.• For a rock to be permeable, it must have
connected spaces.• Influenced by:– Size & sorting• Consistent sorting & large particles = high permeability
– Most permeable rock:• Coarse particles (sandstone, fractured limestone)
Recharge zones
• Area where water can soak into the ground and enter an aquifer.
• NC road sign example
Nicholas.duke.edu
Saltwater intrusion
From Miller’s Living in the Environment
Homework
• Read pages 320 - 325
Output
• Sketch and label a cross section an aquifer