Artesian well

An artesian well is a well that brings groundwater to the surface without pumping because it is under pressure within a body of rock or sediment known as an aquifer.[1] When trapped water in an aquifer is surrounded by layers of impermeable rock or clay, which apply positive pressure to the water, it is known as an artesian aquifer.[1] If a well were to be sunk into an artesian aquifer, water in the well-pipe would rise to a height corresponding to the point where hydrostatic equilibrium is reached.[2][3] Fossil water aquifers can also be artesian if they are under sufficient pressure from the surrounding rocks, similar to how many newly tapped oil wells are pressurized.The first mechanically accurate explanation for artesian wells was given by Al-Biruni.
Artesian aquifer scheme:
  1. Aquifer
  2. Impervious strata
  3. Infiltration area
  4. Artesian well
  5. Saturation level
  6. Subartesian well
  7. Artesian spring
Geological strata giving rise to an artesian well
Schematic of an artesian well
U.S. Navy Seabees tapping an artesian well in Helmand Province , Afghanistan
Artesian well near the Myllylähde spring in Alastaro , Finland
Great Artesian BasinAquiferstrataSeabeesHelmand Provincegroundwaterimpermeablehydrostatic equilibriumFossil wateroil wellsAlastaroelevationAl-BiruniArtoisFranceCarthusianFluid mechanicsHydrogeologyList of artesian wells in the United StatesUnited States Geological SurveyFrances Gies and Joseph Gies