well, Artesian << ahr TEE zhuhn, >> is a well that taps ground water which is under pressure. Such water can rise to the surface without the aid of a pump if enough pressure exists. The term artesian well also refers to any extremely deep water well.
Most artesian wells tap a layer of porous material filled with ground water. This layer, called an aquifer, may lie between two layers of clay or some other material that does not let water through. The aquifer may be tilted, allowing rainfall to refill it at its upper end. This water seeps down in the aquifer, supplying the reservoir of ground water. An artesian well flows naturally because of the pressure exerted on water in the aquifer by water entering at the aquifer’s upper end.
Areas where artesian wells can be drilled are called artesian basins. The word artesian comes from Artois, a province in France, where artesian wells were first drilled during the 1100’s.
