2. CONTENT
Introduction
Hydrological cycle
Influencing Factors
VERTICAL DISTRIBUTION OF GROUND WATER
ZONE OF AERATION
Capillary zone
WATER TABLE
ZONE OF SATURATION
Conclusion
References
3. INTRODUCTION
Groundwater hydrology may be defined as the
science of the occurrence, distribution and
movement of water below the surface of the earth.
Groundwater commonly understood to mean
occupying all the voids within a geological stratum.
Groundwater “out of sight-out of mind”
4. HYDROLOGICAL CYCLE
The forms of water occurring at surface and ground
water related by the concept of hydrologic cycle.
5. The factors that control the occurrence and
distribution of ground water in a region:
• Topography
• Morphology
• Soil conditions
• Lithology of the area
• Structural Aspect
Influencing Factors
Topography
8. VERTICAL DISTRIBUTION OF GROUND
WATER
The vertical distribution of
ground water mainly
divided into two zones:
Zone of Aeration
Zone of Saturation
9. ZONE OF AERATION
The zone of Aeration
consists of interstices
occupied partially by water
and partially by air.
The zone of Aeration is
subdivided in to three types
1. Soil water
zone
2. Intermediate
zone or
vadose zone
3. Capillary zone
10. CONTD…
Water in the soil-water zone exits at less
than saturation except when excessive
water reaches the ground surface as from
rainfall or irrigation “its thickness varies
with soil type”
The amount of water present in the soil
water zone depends primarily on the
recent exposure of the soil to moisture
.
Under hot arid conditions a water
vapour equilibrium tends to become
established between the ambient air
and the surface of fine grained soil
particles . As a result, only thin films of
moisture knows as “hygroscopic
water” remain adsorbed on the
surfaces.
For coarse grained materials and
where additional moisture is available.
11. CONTD..
Soil water zone was classified by ‘Briggs’ into three
subzones depending on the concentration of
moisture content they are:
1.Hygroscopic water.
2.Capillary water .
3.Gravitational water.
12. CONTD..
1.Hygroscopic water:
Absorbed from the which forms thin
layer of moisture on soil particles
surface. The force are large so that
this water is unavailable to plants.
2. Capillary water: Exists as
continues films around the soil
particles and it is yield by surface
tension and is moved by capillary
action and is available to plants.
3. Gravitational water : Is
excess soil water which drains
through the soil under the influence
of gravity.
Capillary water
13. 2.INTERMEDIATE VADOSE ZONE
The intermediate vadose zone
extends from the lower edge of the
soil water zone to the upper limit of
the capillary zone.
The thickness may vary from zero,
where the bounding zones merge
with a high water table approaching
ground surface to more than 100m
under deep water table conditions.
Non moving vadose water is held in
place by hygroscopic and capillary
forces temporary excesses of water
migrate downward as gravitational
water.
14. 3.CAPILLARY ZONE
The capillary zone extends from the water table up
to the limit of capillary rise of water or capillary
fringe is one which lies immediately above the zone
of saturation . The water available in the zone is
termed as capillary water.
Water is drawn up from the zone of saturation
through capillary action and suspended by capillary
force .
Thickness of this zone is dependent upon the
texture of soil formation, above the zone of
saturation .if the size of pores is fine the upward
movement of water through the soil is
comparatively more causing greater thickness .
15. CONTD..
The important features of capillary fringe are
1. Its lower part, which is immediately adjacent to
the water table, contained water in all pores.
2. Moisture content is being equal to the porosity
of soil formation .
3.Water pressure is less than the atmospheric
pressure.
4. Thickness of capillary fringe tends to get
increased or decreased, depending upon water
table fluctuation.
16. WATER TABLE
The subsoil horizon below the surface is called as the zone of aeration or
vadose zone. Below this zone there is a water saturated media is called as
the ground water.
The upper most surface of the zone of saturation is termed as the water table.
Water table forms the boundary between the zone of aeration and zone of
saturation.
17. ZONE OF SATURATION
In Zone of saturation all interstices are filled with
water under hydrostatic pressure.
In the zone of saturation, groundwater fills all of the
interstices; hence the porosity provides a direct
measure of the water contained per unit volume.
A portion of the water can be removed from
subsurface strata by drainage or by pumping of a
well. However, molecular and surface tension
forces hold remainder of the water in place.
18.
19. CONCLUSION
Vertical Distribution gives the distribution of water in
varies stages.
To access the movement of water either
horizontally or vertically based on geological
condition.
Most of the well which gives high yield it means to
gives the surface to sudsurface runoff easily
through vertical distribution of ground water.
It helps the quantity of water availability in the
system.
20. REFERENCES
David Keith Todd, Groundwater Hydrology, second
edition, Wiley India, pp 31-37, 2006.
C.W. Fetter, Applied Hydrogeology, second edition,
CBS, pp 4-7, 1990.
R. C. Ward, principles of Hydrology, McGraw-hill,
pp 16-18, 1967.
www.usgs.com/watertable/info
www.wikipedia.org/water/table
http://site.iugaza.edu.ps/ymogheir/files/2011/02/Ch2
-Occurrence-of-Groundwater.pdf
