Card Set Information

2010-04-13 16:06:50

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  1. What is groundwater?
    • groundwater fills the open spaces in rocks, sediment, and soil beneath the surface
    • it is an important resource for domestic, industrial, and agricultural use
  2. What properties of earth materials allow them to absorb water?
    • porosity
    • permeability
  3. What is the difference between porosity and permeability?
    • porosity- proportion of a rock or sediment that is open space (pore space), pores may contain air, water, or oil/gas
    • permeability-ability to allow the passage of fluid in its pore spaces (measure of the rate at which water oil, or gas can flow through a rock
  4. What is the water table?
    the top of the zone of saturation
  5. What is the capillary fringe?
    layer above the water table where some water is pulled upward by surface tension
  6. What is the Vadose zone?
    pore spaces contain mostly air
  7. What is the zone of saturation?
    pore spaces contain mostly water
  8. How does groundwater flow?
    downhill moves in response to differences in water and pressure and elevation, slope of the water table, and permeability
  9. How fast does groundwater flow?
    • very slowly, as fast as 250 meters a day
    • a few cm a day is typical for most aquifers
  10. What is the difference between aquifer and an aquitarde?
    • Aquifer- porous and permeable layer that contains groundwater
    • Aquitarde (aquiclude)- impermeable layer that blocks flow
  11. Whats the difference between confined aquifer and unconfined aquifer?
    Confined aquifers- water flows between two aquitardes (sandwiched in)

    Unconfined aquifers- water table not covered by aquiclude or aquitarde
  12. How do you make a water well?
    made by digging or drilling into the zone of saturation. Most wells must be pumped to bring water to the surface.
  13. What is the cone of depression?
    occurs in an aquifer when groundwater is pumped from a well
  14. What is an artesian well?
    • in confined aquifers water is under pressure and can rise to a level above the top of the aquifer
    • water wil flow naturally to the surface without pumping
  15. What are recharge and discharge?
    Recharge- the process of adding new water to the water table

    Discharge- takes place when the water table intersects the ground surface (springs) or by pumping from wells
  16. What is a spring?
    water flows naturally from rock onto land surface
  17. What aquifer does Lafayette's water come from?
    Chicot Aquifer
  18. What is land subsidence?
    Land subsidence occurs when large amounts of ground water have been excessively withdrawn from an aquifer. The clay layers within the aquifer compactand settle, resulting in lowering the ground surface in the area from which the ground water is being pumped.
  19. What is saltwater intrusion?
    is the movement of saline water into freshwater aquifers. Most often, it is caused by ground-water pumping from coastal wells,[1] or from construction of navigation channels or oil field canals.
  20. What is karst topography?
    Landforms created by dissolution of limestone
  21. What are caves?
    caves form as a result of dissolution of carbonate rocks
  22. What are depostional features of caves?
    stalactites-icicle-shaped mass of calcite attached to the roof of a limestone cavern

    stalagmites-A mineral deposit of calcium carbonate, in shapes similar to icicles, that lie on the ground of a cave
  23. What are sinkholes?
    circular surface depressions
  24. What are karst towers?
    remains of a cave
  25. How are hot springs and geysers formed>
    Hot springs- water is circulated deep, where it is heated by magma or cooling igneous rocks

    Geysers- forcefully eject water and steam because of constrictions in the plumbing system