GROUNDWATER GEO 2

  1. Groundwater
    water occurs in soil and rock
  2. GROUNDWATER BASICS
    • A.POROSITY- storage capacity of rocks or sediment
    • B.PERMEEABILITY-how fast water moves through rocks or sediments
    • C.AQUITARDS(water closed)- impermeable rocks that prevent groundwater movement
    • D. AQUIFIERS (water bearing)
    • 1. Permeable rocks that store groundwater
    • 2. Unconfined aquifiers
    • a.Zone of aeration-layer in which pore spaces are filled with air
    • b. Zone of satuaration- layer in which all pore spaces are filled with water
    • c. Water table
    • i. Tope of the zone saturation
    • ii. Fluctuates during the year
    • iii. Mimics overlying topography (ground surface)
    • d. Unconfined aquifiers have an aquitard below but NOT above
    • e. Water table wells are drilled into unconfined aquifiers
    • i. When water is withdrawn from an unconfined aquifier, a cone of depression forms around well
    • f. The Edwards Aquifier is unconfined in the recharge zone
    • g. Perched water table
    • i. Localized water table above the main water table
    • ii.Form where there is an aquitar in the zone of aeration that traps water above the main water table
    • 3. Confined aquifiers
    • a. Have quitards both above and below the aquifier
    • b. Artesian-pressure surface
    • c.Artesian wells- water in the aquifier is under pressure and will rise to the level of the artesian pressure surface
    • d. The Edwards Aquifer is conifined underneath SAC
  3. Springs and Geysers
    • A. SPRINGS-form where the water table intersects the ground surface
    • B.HOT SPRINGS-form where water is warmer than mean annual air temp
    • C. GEYSERS-intermittent hot springs in which hot water errupts followed by stream
  4. Enviromental Problems
    • A. MINING AND AQUIFER
    • 1. Withdrawing groundwater faster than recharge occurs
    • 2. High plains aquifer-North Texas to South Dakota
    • B. GROUND SUBSIDIENCE
    • 1.Water helps hold grains apart
    • 2.Withdrawal of water allows grains to compact more closely
    • 3.San Joaquin Valley
    • a. Withdrawal of groundwater between 1925 and 1975 caused the ground surface to subside up to 28ft in places
    • C. Groundwater pollution-sewage, chemical discharge, landfills. etc
  5. CAVES AND KARST TOPOGRAPHY
    • A. MOST CAVES ARE FORMED AT OR SLIGHTLY BELOW THE WATER TABLE IN THE ZONE OF SATURATION IN LIMESTONES
    • B. DEPOSITION OF THE TRAVERTINE OCCURS IN ZONE OF AERATION
    • C.KARST TOPOGRAPHY
    • 1. Surface features that form in humid areas underlain by limestone
    • a. Sinkholes- form where the roof of cave collapses(slow or quick) leaving an opening at ground surface
    • b. Disappearing streams-form where a stream flows into a sinkhole
Author
Anonymous
ID
24369
Card Set
GROUNDWATER GEO 2
Description
GROUNDWATER GEO 2
Updated