Springs,+Wells,+and+Aquifers

[[image:240px-Artesian_Well.png caption="Geological strata giving rise to an Artesian well."]][[image:175px-Artesianwell.jpg caption="An artesian well."]]
====Aquifer- An aquifer is an underground layer of water-bearing permeable rock or unconsolidated materials (gravel, sand, silt, or clay) from which groundwater can be usefully extracted using a water well. The study of water flow in aquifers and the characterization of aquifers is called hydro geology. Related terms include: an aquitard, which is an impermeable layer along an aquifer, and an aquiclude (or aquifuge), which is a solid, impermeable area beneath an aquifer. The surface of saturated material in an aquifer is known as the water table.====

Artesian aquifer: this is where asia gets there water from.An **artesian aquifer** is a [|confined aquifer] containing [|groundwater] that will flow upwards through a well without the need for  __[|pumping]__. Water may even spurt out of the ground if the natural pressure is high enough. An aquifer provides the water for an artesian well. An aquifer is a layer of soft rock, like limestone or sandstone, that absorbs water from an inlet path. Porous stone is confined between impermeable rocks or clay. This keeps the pressure high, so when the water finds an outlet, it overcomes gravity and goes up instead of down.

Sparta aquifer: media type="youtube" key="f1ZngnxpVjc" height="295" width="480"

Water wells:
A **water well** is an excavation or structure created in the ground ––by digging, driving, boring or drilling to access water in underground [|aquifers]. The well water is [|drawn] via an [|electric submersible pump] or a [|mechanical pump] (eg from a water-pumping windmill . It can also be drawn up using containers, such as buckets, that are raised mechanically or by hand. Although not essential, a [|storage tank with a pressure of 40-60 psi] is usually added to the system (after the pump), so the [|pump] does not need to operate constantly.  To reduce the electricity required to pump up the water, often, a [|cistern] is also added along with a small second pump (see schematic below).Wells can vary greatly in depth, water volume and water quality. Well water typically contains more minerals in solution than surface water and may require treatment to [|soften the water] by removing minerals such as [|arsenic], [|iron] and [|manganese].

Springs: A place where [|groundwater] discharges upon the land surface because the natural flow of groundwater to the place exceeds the flow from it. Springs are [|ephemeral], discharging intermittently, or permanent, discharging constantly. Springs are usually at mean annual air temperatures. The less the discharge, the more the temperature reflects seasonal temperatures. Spring water usually originates as rain or snow (meteoric water). Hot-spring water may differ in composition from meteoric water through exchange between the water and rocks. Common minerals consist of component oxides. Oxygen of minerals has more 18O than meteoric water. Upon exchange, the water is [|enriched] in 18O. Most minerals contain little deuterium, so that slight deuterium changes occur. Some hot-spring waters are acid from the [|oxidation] of [|hydrogen sulfide] to [|sulfate]. Mineral spring waters have high concentrations of solutes and wide ranges in chemistry and temperatures; hot mineral springs may be classified as hot springs as well as mineral springs. Most mineral springs are high either in [|sodium chloride] or sodium [|bicarbonate] (soda springs) or both; other compositions are found, such as a high percentage of [|calcium sulfate] from the solution of [|gypsum]. The chemical compositions of spring waters are seldom in chemical equilibrium with the air. Groundwaters whose [|recharge] is through grasslands may contain a thousand times as much CO2 as would be in equilibrium with air, and those whose recharge is through forests may contain a hundred times as much as would be in equilibrium with air. Sulfate in groundwater may be reduced in the presence of organic matter to H2S, giving some springs the [|odor] of rotten eggs. //See also// [|Geyser]; [|Ground-water hydrology].