Groundwater

Fresh water amounts to less than _ of the water on Earth, and groundwater is only _ of the water in Earth.

Groundwater

is also often withdrawn for agricultural, municipal, and industrial use by constructing and operating extraction wells.

groundwater hydrology

The study of the distribution and movement of groundwater is hydrogeology, also called

Groundwater

is used for drinking water by more than 50 percent of the people, including almost everyone who lives in rural areas. The largest use for groundwater is to irrigate crops.

saturated zone

The area where water fills the aquifer is called the

water table

The top of this saturated zone is called the

water table

may be located only a foot below the ground’s surface or it can sit hundreds of feet down

Saturated Zone or phreatic zone

this zone also known as groundwater zone is the space in which all the pores of the soil are filled with water. the water table forms its upper limit and marks a free surface.

Zone of Aeration

n this zone the soil pores are only partially saturated with water. the space between the land surface and the water table marks the extent of this zone.

Soil water Zone

this lies close to the ground surface in the major root band of the vegetation from which the water is lost to the atmosphere by evapotranspiration.

Capillary fringe

in this water is held by capillary action. This zone extends from the water table upwards to the limit of the capillary rise.

Intermediate zone

this lies between the soil water zone and the capillary fringe. The thickness of the zone of aeration and its constituent subzones depend upon the soil texture and moisture content and vary form region to region. The soil moisture in this zone of aeration is of importance in agricultural practice and irrigation engineering.

Aquifer

an aquifer is a saturated formation of earth material which not only stores water but yields it in sufficient quantity.

Aquitard

it is a formation through which only seepage is possible and thus the yield is insignificant compared to aquifer. It is partly permeable. A sandy clay unit is an example of aquitard. Through an aquitard appreciable quantity of water may leak to an aquifer below it.

Aquiclude

it is a geological formation which is essentially impermeable to the flow of water. it may be considered as closed to water movement even though it may contain large amounts of water due to its high porosity. Clay is an example of an aquiclude.

Aquifuge

it is a geological formation which is neither porous nor permeable. There is no interconnected rock without any fractures is an aquifuge.