Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water...
-
Upload
calvin-franklin -
Category
Documents
-
view
227 -
download
2
Transcript of Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water...
![Page 1: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/1.jpg)
Chapter 11 – WATER UNDER THE GROUND
![Page 2: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/2.jpg)
Freshwater Underground• Ground water
– Subsurface water contained in pore spaces in regolith & bedrock
![Page 3: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/3.jpg)
Freshwater Underground• Zone of aeration
– Mix of air & water
• Zone of saturation– Saturated with
water• Water table
– Top of saturated zone
![Page 4: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/4.jpg)
• How groundwater moves– Porosity
• % of total volume of rock body or regolith made of open spaces (pores)
– Permeability• Measure of how easily a solid
allows fluids to pass through it
Freshwater Underground
![Page 5: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/5.jpg)
• How groundwater moves– Hydraulic gradient
• Change in elevation divided by distance• Used to
determine rate of groundwater flow
Freshwater Underground
![Page 6: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/6.jpg)
• How groundwater moves (continued)– Percolation
• Groundwater seeps downward
– Recharge• Replenishment of
groundwater– Discharge
• Subsurface water leaves saturated zone
• Becomes surface water– Spring
• Occurs where water table intersects land surface
Freshwater Underground
![Page 7: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/7.jpg)
• How groundwater moves (continued)– Other methods of discharge
• Hot springs• Geysers
Freshwater Underground
![Page 8: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/8.jpg)
• Where groundwater is stored– Aquifer
• Rock body or regolith that is water saturated, porous, & permeable
– Aquiclude• Layer of
impermeable rock
Freshwater Underground
![Page 9: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/9.jpg)
• Where groundwater is stored– Aquifer
• Unconfined• Confined• Potentiometric
surface– Artesian well
Freshwater Underground
![Page 10: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/10.jpg)
• Groundwater depletion– Cone of depression
• Cone-shaped dip in water table due to pumping
– Groundwater mining• Rates of groundwater withdrawal
continuously exceed rate of recharge
Freshwater Underground
![Page 11: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/11.jpg)
• Groundwater depletion (continued)– Land subsidence
• Compaction– Salt water intrusion
Freshwater Underground
![Page 12: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/12.jpg)
• Groundwater contamination– Contamination
Freshwater Underground
![Page 13: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/13.jpg)
• Dealing with groundwater issues– Enhanced recharge– Conservation– Other sources
• Desalination (i.e. distillation; reverse osmosis; electrolysis)
• Icebergs
Freshwater Underground
![Page 14: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/14.jpg)
• Natural methods– Filtration– Decomposition– Bacterial action
• Human methods– Exterior treatments– Dilution– Chemical
treatments
Freshwater Underground
![Page 15: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/15.jpg)
15
Groundwater in the U.S.
![Page 16: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/16.jpg)
16
• Groundwater Mining– Recharge rate vs. consumption rate
• Ogallala Aquifer: largest aquifer in U.S. – 225,000 sq miles– Found in 8 states– 30,000 years of
water accumulation
Groundwater in the U.S.
![Page 17: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/17.jpg)
Ogallala Aquifer
![Page 18: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/18.jpg)
Groundwater in Nebraska
![Page 19: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/19.jpg)
Groundwater in Nebraska
![Page 20: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/20.jpg)
What areas seem best suited for groundwater withdrawal?
Why do you think these areas are not utilized?Answer: The Nebraska Sandhills However, Crops do not grow well in sand, so the area is primarily used for ranching.
Groundwater in Nebraska
![Page 21: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/21.jpg)
• When groundwater dissolves rock– Carbon dioxide + water =
carbonic acid• Adds acid to water in atmosphere
& underground
– Calcite + carbonic acid = dissolution
• Calcite dissolves
Freshwater Underground
![Page 22: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/22.jpg)
• Factors of dissolution– Rock composition– Extent of rock fracturing,
jointing, & bedding– Acidity of water– Climate
Freshwater Underground
![Page 23: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/23.jpg)
• When groundwater dissolves rock– Karst topography– Sinkholes– Disappearing streams
Freshwater Underground
![Page 24: Chapter 11 – WATER UNDER THE GROUND. Freshwater Underground Ground water –Subsurface water contained in pore spaces in regolith & bedrock.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649ec45503460f94bceb77/html5/thumbnails/24.jpg)
• When groundwater dissolves rock– Cave
• Underground open space• Cavern = system of connected
caves • Stalactites• Stalagmites• Columns (pillars)
Freshwater Underground