ground water: h 2 o beneath the earth’s surface aquifer: rock or sediment that stores ground water
TRANSCRIPT
Ground water: H2O beneath the Earth’s surface
Aquifer: rock or sediment that stores ground water
• Porosity: empty space in a rock
• Permeability: water passes through• • Sandstone -- highly permeable -- large grains• Limestone -- low permeability---- pores are
NOT connected
Clay -------impermeable.
Zones of Aquifers:A) Zone of Saturation: area in which pore
space is completely filled with water
B) Zone of Aeration: upper surface of ground water which has lots of pores for air and tiny animals
Water Table: upper boundary of the zone of saturation
Illustrate on the board
Depth of the water table depends on:A) how much water humans useB) amount of rainfallC) permeability of aquiferD) surface topography
Pollution has NO effect on the depth of table
Water table is high in heavy rainfall
Water table is low in times of drought
Special features of ground water:A) artesian well: a sloping layer of
permeable sandwiched between 2 layers of impermeable rock
B)Ordinary springs: occur when the ground surface drops below the water table
C) Hot springs: hot groundwater of at least 37oC that rises to surface. As it cools, minerals are deposited along the edge
D) mudpots: hot water in a sticky muddy depression. (Yellowstone )
E) Geysers: hot springs that stay below ground and form steam. The hot water forms steam which produces enough pressure that it blows up
Chemical Weathering: cause for mineral build up in ground water. This produces:
Hard water: water with minerals
Valley and Ridge has hard water from the Ca in limestone
Hard water will damage pipes and appliances
Karst topography: area that chemical weathering has eat away large sections of bedrock. Valley and Ridge of Va
Because all of the “holes” in rock, polluted groundwater can travel a long way from a pollution sight
Non-point pollution sight: fertilizer from a pasture or field runs into a
stream after a heavy rain
Point pollution sight: a factory dumps waste water into a river through a pipe
Features of Karst Topography:1) Caves:
A) stalagmites: build up at the bottom of a cave. They form as the water filled with carbonate from limestone makes a “Hill”
B) stalactites: build from the top, as carbonate filled water drips from the ceiling of cave
2) sinkholes: circular depression under surface as rock dissolves
3) natural bridges: an uncollapsed rock between sinkholes
4) Caverns: deep underground holes
Soft water---low mineral contentIt will form suds easier and does less damage
to household items
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