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Water-The creation of spring and
subterranean water
Part of the precipitation penetrates the
Earth infiltration . The permeated water
will either flow in the course of inter layer
water currents of the Earth inter flow ,
or as deposits , form subterranean water
basins.
These water basins may form in the following
ways:
1 - in the fine layer of sands which are
formed from the decomposition of a mass of
hard or unpermeative stones
surface water
basin , 2- in a permeative layer of Earth
which is located on an unpermeative one
free normal water basin ,3 - in the
alluviums of an extensive plain alluvial
plain water basin ,4- in a permeative layer
which is located between two unpermeative
layers and has run to the surface of the
Earth as a result of erosion. Depending on
the condition of water under the ground and
also permeation of subterranean layers,
underground waters may run on the surface
of the Earth in a vriety of ways.
A- escaping little permeative lands:
1- springs,springs are in fact underground waters which flow on the surface of the Earth
and in most cases they are formed from rain
waters and / or waters resulted from the
melting of snow,which penetrate into the
ground and flow and stay for some time in
the hollow spaces there mineral cold or
warm waters are not considered among these
waters . How water leaves the ground is
a factor which distinguishes three types of
springs 1-1- flowing springs,in these kinds
of springs,water immediately runs along the
profile of slopes towards valleys,1-2- basin
springs , in these springs water fills
a natural basin , before overflowing along
profile of slopes,1-3- lagoon springs,here
water leaves the ground through a more or
less thick layer and changes the surrounding
land into a lagoon.
2- acqueducts , these are canals which are
dug under the ground from plains towards
mountains so that they cross water bearing
basins and drain their water . To dredg
acqueducts,some wells are usually dug every
30 to 40 meters in their course.The distance
from the source of the acqueduct to the last
well,known as the mother well,varies between
a few meters to a few kilometers. Historical
evidences indicate that Iranians were the
first to make aqueduct.
B - escaping high permeative lands :
in this case water leaves the ground
in the form of springs more in hard
lands full of fractures or passages.
C - escaping fractures :
in this case water leaves fractures.These
fractures might either be in a simple crack
form which are known as crack,or in the form
of a crack accompanied by a displacement of
layers known as fault.
D - Escaping through digging wells :
in this method water is drained by boring
a hole in the ground which gets to the water
basin . The drain of water from wells is
usually carried on by using auxiliary
equipments such as pumps.However,there
is also another kind of well,known as
Artesian it is a well board down to the
point,usually at great depth,at which the
water pressure is so great the water is
forced out of the surface.
