Earth Science

 Infiltration
 Process by which precipitation that has fallen on land trickles into the ground. 
 Zone of saturation
 Region below the Earth’s surface in which groundwater fills all the pores of material. 
 Water table
 Upper boundary of the zone of saturation 
 Zone of aeration
 Area above water table.

  Materials are moist, but not saturated. 

 Permeability
 Tendency of material to let water pass through it. 
 Aquifers
 Water flows through permeable sediment and rock into large pore spaces.
 Aquicludes
 Impermeable layers that are barriers to groundwater flow. 
 Springs
 Natural discharges of groundwater.

 

 Hot springs
 Springs with temperatures higher than the human body. 
 Geyers
 Explosive hot springs. 
 Cave
 Natural underground opening with a connection to the surface. 
 Sinkhole
 A depression in the ground caused by the collapse of a cave 
 Karst topography
 Limestone regions that have sinkholes and disappearing streams. 
 Stalacite
 Hangs from the cave’s ceiling 
 Stalagmites
 Grow from cave floor 
 Drawdown
 Difference between original water table and water level in a pumped well.

 

 Recharge
 Water from precipitation replenishes the water content of an aquifer. 
 Artesian well
 An aquifer that contains water under pressure