Unconfined aquifer

 a zone of saturation with a permeable layer above and an impermeable layer below

Confined aquifer

a zone of saturation with an impermeable layer above and below it

Artesian well

flow of water onto surface under pressure from a confined aquifer

Spring

flow of water on surface that emerges from underground, NOT under pressure from a confined aquifer

Carbonation

reaction of carbonic acid with minerals, dissolves Ca in limestone

* amount of CO2 in the water affects the strength of the acid which affects the rate of dissolution

Surface landforms:

•  Doline (most widely distributed)
• Uvala
• Cockpit and tower karst
• Fluvio karst
• Polje karst
• Labyrinth karst

Underground landforms:

• caves (biggest: mammoth in KY)
  •  features: stalagmites, stalactites, speleothems, column, tufa