International Journal of Geosciences, 2012, 3, 410-429
http://dx.doi.org/10.4236/ijg.2012.32046 Published Online May 2012 (http://www.SciRP.org/journal/ijg)
Hydrogeochemical Variations of Groundwater of the
Northern Jabal Hafit in Eastern Part of Abu Dhabi
Emirate, United Arab Emirates (UAE)
Ahmed Murad1*, Faris Mahgoub2, Saber Hussein1
1Department of Geology, UAE University, Al-Ain, UAE
2WJ Groundwater Ltd., Dubai/Jumierah Lakes Towers, Dubai, UAE
Received March 16, 2011; revised January 27, 2012; accepted March 2, 2012
ABSTRACT
This study is aimed to assess and evaluate the suitability of groundwater of the area located to the south-east of Al-Ain
area in the UAE using hydrogeochemcical approach. The chemical analyses of groundwater samples collected from the
study area showed that the groundwater salinity is high which resulted from heavy groundwater pumping. High chloride
concentrations in groundwater of Mubazarah and Neima might be attributed to the entrapped saline water within the
limestone sequence of Jabal Hafit, or it can be the agricultural activities as it clear from the positive relationship be-
tween Cl− and Br−. High sulphate concentrations in groundwater might be related to the presence of gypsum and anhy-
drite within the limestone sequence of Jabal Hafit. The anionic and cationic compositions of groundwater indicate that
the chloride and sodium ions are the dominant and presence of bicarbonate and sulphate may reflect the mixing of such
water by the recent freshwater through the existing structural lineaments within the study area. The hydrochemical pa-
rameters indicate a relative increase in the concentration of calcium, magnesium and sulphate ions and this could reflect
the influence of carbonates and evaporite sediments.
Keywords: United Arab Emirates; Salinity; Major Cations and Anions; Groundwater; Water Genesis
1. Introduction
The study area is located within the vicinity of Al-Ain re-
gion in which the climate is deficient in rainfall, with a
mean annual rainfall of about 96.4 millimeters [1]. Al-
Ain area is considered to be a better ephemeral surface
water resource in the country due to the occurrence of
flash floods. Ain Al-Faydah (Ain Bu Sukhanah) is the
only spring with Al-Ain area, which is located about 15
Km south of Al-Ain and about 2 km west of Jabal Hafit.
According to El-Shami [2], the spring produces from
Miocene gypsum and clay layers through thin Quaternary
loose sediments. The spring represents the discharge area
of a deep water source which finds its way up through
one of several thrust faults dissecting the area.
The aquifer in the area is recharged by the infiltration
of the precipitation in the interdune areas and gravel
plains and also from Jabal Hafit. Another source of re-
charge includes irrigation water, upward vertical re-
charge from deeper rocks and infiltration of water lost
from the leaky water transmission lines [3].
The domestic water requirements in the region were
met from major aquifers. However, massive increases in
domestic demands due to the annual population growth
rate of up to 8% [4] has meant that groundwater re-
sources have been placed under increasing stress, result-
ing in declining water levels, and increasing groundwater
salinity and a resultant decrease in total production.
The widening gap between groundwater supply and
domestic demand has been met from an expansionist po-
licy of desalination using all types of production process
under an ever increasing responsibility of the private
sector. In 2003, the total domestic wellfield production in
Abu Dhabi Emirate had reduced to only 26 Mm3/yr,
meeting only 17% of the total domestic requirements in
the Eastern Region. Since 1998, production from the do-
mestic wellfields has decreased by over 60% [5].
The objective of this study is to analyze the ground-
water chemistry of the aquifer systems within the study
area in terms of the prevailing natural (climatic, geologi-
cal and hydrgeological) and man-induced (mainly agri-
cultural) conditions and to evaluate the suitability of
groundwater for different purposes.
2. Geological and Hydrogeological Settings
The study area is located South-Easterly from Al-Ain in
*Corresponding author.
C
opyright © 2012 SciRes. IJG

A. MURAD ET AL. 411
the most eastern part of the Emirate of Abu Dhabi. It
comprises Neima area to the north, Mubazarah to the east
and Ain Bu Sukhanah to the west (Figure 1).
Jabal Hafit, the main mountain in the study area, is
composed nearly of limestones and dolomites [6,7]. The
gravel plain consists of a gently inclined gravel and sand
plain, built up of the down-wash material drained by
wadis from the eastern mountains. The continuation of
the wadi courses to the north is marked by a string of pat-
ches of sabkhas, formed at the times of flood due to the
rise of groundwater level [8]. The western part of the
investigation area is dominated by dune fields and most
of the study area is covered by Quaternary deposits. Four
types of Quaternary deposits have been recognized in the
study area and these are fluvial Deposits, desert plain
deposits, sabkha deposits and aeolin sands [9,10].
The geology of Jabal Hafit has significant impact on
the hydrogeology of the area. The water bearing forma-
tions of the study area are mainly composed of alluvial
deposits in the upper most part that underlained by clay,
gypsum, limestone and marl lithofacies (Figure 2). The
depth to water level varies according to the ground ele-
vation and aquifer type. Fifteen large diameter wells have
been drilled in the wellfield of the Mubazarah area with
depths ranging from 90 to 200 meters and yields of 4600
m3/d which mainly are ascribed to fracture permeability
and dissolution. The measured discharge of the wells to the
pond west of the wellfield was 21,000 m3/d. Wells that
produce water with relatively high temperature and spe-
cific conductance are located close to the fold axis of the
Jabal Hafit as compared to wells that produce cooler and
fresher water which are located further from the axis.
Deep fractures may act as conduits to bring thermal and
saline water close to the surface before it cools or be-
comes diluted. The source of the water may be either
meteoric water that rises by hydraulic pressure after hav-
ing descended to a great depth or saline water that as-
cends due to gas pressure or thermal gradient. The flux of
recharge water through Jabal Hafit may be greater than
the lateral or upward flow of saline water into the con-
duits. Therefore, the result is water in the mixing zone
that is brackish. The water in the conduits is heated by
normal geothermal gradient at a depth of approximately
2000 meters below the surrounding land (3000 meters
below the Jabal). The conduits bring the mixed water to
the base of the clastic aquifer where it enters the shallow
regional flow system. The aquifer water cools to near the
ambient aquifer temperature, and becomes even more
dilute. Water levels in the area ranges from 5.71 to 60.94 m
below land surface and the level of water table is declining
in those wells that are frequently pumped or are adjacent
to pumped wells [11].
An old municipal well in Neima area began to flow in
early February 2003 after reportedly being abandoned
Figure 1. Map showing the location of the study area. Inset map showing the location of the UAE and study area relative to
the Arabian Peninsula.

A. MURAD ET AL. 412
Figure 2. Conceptual geohydrologic cross-section of the study area (after [12]).
about 10 years ago because it had dried up. The well is
located about 6 kilometers south of Al-Ain city, and is
about 2 kilometers north of the road at the base of Jabal
Hafit. The well was supposedly drilled some 15 years
ago to a depth of 550 ft [12]. Fresh and brackish water of
limited areal extent is found within limestones in the
Jabal Hafit area. In the vicinity of the rock outcrop, the
limestone aquifer is unconfined and further (down dip)
away from the rock outcrop, the limestone aquifer is either
semi-confined or confined by underlying and overlying
rock units [11].
Ain Bu Sukhanah or sometimes called Ain Al-Faydah
is located less than 2 km to the west of Jabal Hafit. It
apparently discharges from a gypsum aquifer, probably
well karstified adjacent to the western side of Jabal Hafit.
The discharge of Ain Bu Sukhanah spring reflects no
direct relation with groundwater levels in the study area
when groundwater level data of 1990 and 1991 are com-
pared. The groundwater level at the nearby observation
well declined from 34.1 in 1990 to 42.2 m in 1991 below
ground surface. Whereas the spring discharge increased
from 1.58 × 106 m3/yr in 1990 to 2.5 × 106 m3/yr in 1991
[13]. If it is assumed that 60 mm (out of 100 mm) infil-
trates then some 2.5 million m3 is estimated as entering
the limestone mass. This quantity corresponds quite closely
to the annual yield of the spring suggesting that the Jabal
Hafit is the feeding area for the spring [14]. A possible
explanation for the brackish water at Bu Sukhanah spring
is that fresh water of the Jebel Hafit becomes brackish on
its way through the gypsum.
3. Methodology
For this study, 53 water samples were collected from
governmental and private wells (Figure 3). In addition, 3
surface water samples were collected from different sur-
face water localities in the study area.
The temperature, Electrical Conductivity (EC) (µS/cm)
and Total Dissolved Solid (TDS) contents in mg/l were
measured directly in the field. The collected groundwater
samples were then analyzed for major cations (K+, Na+,
Mg+ and Ca2+) and major anions (3,4
2
HCO 2 SO

, Cl−) in
the Central Laboratories Unit (CLU) at UAE University.
All chemical data and their processes and acquisitions
are listed in the Appendix.
4. Results and Discussions
The main measured physical properties of the ground-
water in the study area including, electrical conductivity
(EC), total dissolved solids (TDS), temperature and che-
mical properties of the major ions are presented.
4.1. Physical Properties
The electrical conductivity of groundwater samples col-
lected from the study area varied between 2.989 mS/cm
in a farm west of Neima (Well No. 9) and 27.188 mS/cm
in Ain Bu Sukhanah (Well No. 34) (Figure 4). The data
shows that in the north (Neima Area), the EC values are
less than 10 mS/cm, while in Mubazzarah area , the EC
values between 15 and 25 mS/cm, and to the west of

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Figure 3. Map showing the location of groundwater samples in the study area.
Jabal Hafit at Ain Bu Sukhanah, the EC values exceed 30
mS/cm.
These high EC values might result from using the
groundwater in these areas in agricultural activities. In
the study area, the total salinity of groundwater ranges
between 1910 and 17,400 mg/l, with a mean value of
6714 mg/l (Figure 5). The salinity increases from east to
west in the direction of groundwater flow. The higher
salinity content is recorded for the central and western
regions (Mubazarah and Ain-Bu Sukhanah areas), whe-
reas at Neima area in the north, it is quite low and in-
creases towards the south. Groundwater samples of the
study area are classified as brackish except Wells No. 34,
36 and 38 which are of saline water based on USGS/
NDC classification [3]. Using ground-water for irrigation
purposes is the main reason for high TDS values as well
as the lithological constitutes of the water-bearing forma-
tion. The temperature of the collected groundwater sam-
ples in the study area varies between 29˚C and 49.1˚C
with a mean value of 35.59˚C. The temperature increases
from west to east, opposite to the direction of groundwa-
ter flow. Where as, Mubazarah is characterized by the
highest water temperature because of thermal origin of
groundwater in that area.

A. MURAD ET AL. 414
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Figure 4. Iso-Electrical Conduc tivity (µS/cm) contour map of groundwater samples colle cted from the study area.
4.2. Chemical Properties
The major cations in water are potassium (K+), sodium
(Na+), magnesium (Mg+2), calcium (Ca2+) and the major
anions are chloride (Cl–), sulphate (4
SO ) and bicarbon-
ate (3). It is noticed that the cation charge balance
is too high and exceeded the 5%. This abnormal of charge
balance mainly attributed to high groundwater salinity as
it is indicated by Murad (2004) in eastern part of the
UAE. Each of these constituents and their relationship to
each other are discussed below and presented in the Ap-
pendix.
2
2
HCO 
4.2.1. Major Cations
The majority of the groundwater samples of the study
area has the cationic order of: Na+ > Ca2+ > Mg2+ > K+.
Sodium ion concentrations in groundwater of the study
area ranged from 386.5 mg/l at northwest of Mubazarah
in Neima area (Well No. 31) to 4953.5 mg/l at Ain Bu
Sukhanah (Well No. 38). It is clear that the concentration
of sodium is low at Neima and the northern part of the
study area and it is high in While Mubazarah and Ain Bu
Sukhanah. The positive relationship between sodium and
chloride (r2 = 0.81) (Figure 6) is a strong evidence for
extensively using of brackish groundwater for irriga-
tion.
The most common form of calcium in sedimentary
rocks is carbonates, particularly as limestone or dolomite,
which are dominant in the study area. The calcium ion
concentration in groundwater of the study area ranged
from 110.7 mg/l at Neima (Well No. 47) to 1813 mg/l at
Ain Bu Sukhanah (Well No. 34 west of Jabal Hafit). The
calcium concentrations of groundwater samples showed

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Figure 5. Iso-salinity (mg/l) contour map of groundw ater in the study area.
R
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= 0.8111
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Figure 6. The relationship between sodium and chloride
concentrations for the groundwater in the study ar ea.
a gradual increase from east to west in the direction of
groundwater flow. High calcium ion concentrations en-
countered in Ain Bu Sukhanah. The calcium abundance
might result from the limestone dissolution of Jabal Hafit
[15].
The magnesium ion (Mg2+) concentrations in fresh
water are generally less than that of calcium because of
low geochemical abundance of magnesium [16]. The
concentration of Mg2+ in collected groundwater samples
in the study area ranged from 120 to 5173 mg/l. The
maximum Mg2+ concentrations exist in the western side
of Jabal Hafit (Ain Bu Sukhanah). The presence of
dolomite in Jabal Hafit could be elevated the magnesium
concentration at Ain Bu Sukhanah as the dolomite is the
main source of magnesium in groundwater [17].
The natural sources of potassium in water are the ig-

A. MURAD ET AL. 416
neous rocks as feldspars (orthoclase and microcline),
some mica and sedimentary rocks as silicate and clay mi-
nerals [17]. The potassium content ranges between 25.7
mg/l at Neima (Well No. 10) and 1656.8 mg/l at Ain Bu
Sukhanah (Well No. 38). In general, potassium ion con-
centrations are low at Neima and Mubazarah areas, while
high K+ concentrations are recognized in the west of Ja-
bal Hafit at Ain Bu Sukhanah. This high potassium con-
centration can be attributed to the presence of clay layer,
overlained the gypsum aquifer of Ain Bu Sukhanah.
4.2.2. M ajor Anions
The sequence of the major anions in the majority of
groundwater of the study area has the order of: Cl– >
> 3. The chloride ion concentrations in the
study area range between 430 mg/l at Neima (Well No. 9)
and 10,000 mg/l in Ain Bu Sukhanah (Well No. 38). Low
values of chloride concentration are encountered at the
farms west to Neima, while high values are observed at
Mubazarah and Ain Bu Sukhanah. One possible explana-
tion for the high concentration of chloride in Mubazarah
and Neima is the entrapped saline water within the lime-
stone sequence of Jabal Hafit, or it can be the agricultural
activities from the positive relationship between Cl– and
Br– (Figure 7).
2
4
SO 2 HCO 
2
Sulphate ions (4
SO ) are derived from gypsum
(CaSO4·2H2O) or anhydrite (CaSO4) in sedimentary rocks
[15]. These two minerals are present in the study area as
thick beds or streaks in the limestone strata and are suffi-
ciently soluble to cause water in contact with them to be
high in sulphate [18]. The value of sulphate concentra-
tions in the study area ranged between 495 mg/l at Muba-
zarah (Well No. 1) and 6280 mg/l in the south Ain Bu
Sukhanah (Well No. 35). Sulphate ion concentrations are
low at Mubazarah; while Neima and Ain Bu Sukhanah
are characterized by high concentrations which might be
related to the presence of gypsum and anhydrite within
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-
(m g/l)
Cl
-
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–
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Br
–
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Figure 7. The relationship between chloride and bromine
for the groundwater in the study ar ea.
the limestone sequence of Jabal Hafit.
Most bicarbonate ions (3) in groundwater are
derived from carbon dioxide in the atmosphere and soils,
and by dissolution of carbonate rocks [17]. Bicarbonate
concentrations in groundwater of the study area ranged
from 65.07 mg/l south Mubazarah (Well No. 45) to 520.5
mg/l south Neima (Well No. 47). The concentration of
bicarbonate shows a steady increase in the north-west
direction, where Neima is characterized by high bicar-
bonate concentrations. Dissolution of Jabal Hafit carbon-
ate considered the main source for releasing bicarbonate
to the groundwater in the study area.
2
HCO 
4.2.3. Hydrochemical Water Types
The water type is represented by each anion and cation
that exceeds 15 equivalent percentages, arranged from
the lowest to the highest cationic and anionic concentra-
tions [19]. Four anionic groups with their 14 equivalent
cationic combinations are distinguished and give rise to
the different water types (Appendix). The anionic and
cationic compositions of groundwater indicate that the
chloride and sodium ions often acquire the highest con-
centrations. While that, the sulphate with magnesium and
calcium ions compositions reveal the second order in
their concentrations. The intermediate concentration of
bicarbonate and sulphate may be characterized the mix-
ing of such water by the recent fresh water through the
existing structural lineaments within the study area. This
hypothesis is mainly supported by piper diagram (Figure
8) as most of the samples lie on the portions of domi-
nancy of sulpahte and chloride which suggests seawater
of relatively low freshening.
The predominance of sulphate anion concentration
within Cl-sulphate group reflects the depth and distance
from the catchment area as well as the leaching processes
of the evaporitic rock constituents that enrich with cal cium,
Figure 8. Piper diagram for groundwater samples from the
study area.

A. MURAD ET AL.
IJG
417
4.2.4. Hydrochemical Parameters magnesium and sulphate ions. A water type zonation
map is constructed to show the spatial variation of diffe-
rent water types within the study area (Figure 9).
About fifty percent of the analyzed groundwater samples
indicate that the ratio of Na+/C1− in meq/l is generally
Figure 9. Water type zonation map for the study area.
C opyright © 2012 SciRes.

A. MURAD ET AL. 418
less than unity indicating the marine water origin, while
that the others reveal values more than unity to reflect
meteoric water genesis. The hydrochemical parameters in
meq/l of K+/C1–, Na+/C1–, Ca2+/Cl–, Mg2+/Cl– and
4/CI− are compared with the values of the standard
seawater compositions [20] which are 0.0181, 0.8537,
0.0385, 0.1986, and 0.103 respectively. The calculated
hydrochemical parameters relative to the seawater stan-
dard indicted a relative increase in the concentration of
calcium, magnesium and sulphate ions.
2
SO 
This is highly reflecting the influence of the existing
water bearing formations such as carbonate and evaporite
sediments. In addition, a relatively high temperature of
the existing groundwater assists the solubility of such
ions through the water-rock interaction. The adsorbed so-
dium ions to the shaly sediments are effectively sub-
jected to leaching by invading the meteoric water [21].
4.2.5. Water Genesi s and Hypothetic al Sal t
Combinations
The interpretation of chemical analyses of collected
groundwater samples showed that the Na2SO4 is origi-
nated from deep percolation and NaHCO3 is from surface
and shallow meteoric water conditions whereas (K + Na) −
(Cl/SO4) < 1 and (K + Na) − (Cl/SO4) > 1). In addition,
the interpretation reflects the meteoric water genesis,
where the ionic concentrations of the potassium and so-
dium ions are greater than chloride ions in solution.
Wells No. 7 - 15, 28 - 32, 35, 37, 38, 40, 46, 47, 50, 51 -
54 represent the distribution of such water genesis within
the area of investigation.
In spite of the meteoric origin of the water samples,
salts of temporary hardness in the solution are not domi-
nant and represented only by Ca (HCO3)2 except sample
no. 47. On the other hand, salts of permanent hardness
are of obvious existence within most of the samples and
represented by MgSO4 and CaSO4. The appearance of
such salts may be affected by the leaching processes of
lithological constituents that rich in calcium, magnesium
and sulphate ions as well as lacking the recharging
sources. The leaching processes of deep percolating wa-
ter that occurs among these lithological constitutes which
contain groundwater of relatively warm or hot (about
40˚C) makes enrichment of calcium, magnesium and
sulphate ions especially under over pumping perform-
ance and the absence of proper water management. The
NaHCO3 water genesis with the hypothetical salt of KCl,
NaCl, MgCl2, CaCl2, CaSO4 and Ca (HCO3)2 is repre-
sented by well no. 55. The occurrence of MgCl2 and
CaCl2 water types within the salt combinations might
reflect the upward leakage of deep marine water origin in
which the water reserves its meteoric genesis. On the
contrary, the other groundwater samples indicate the ap-
pearance of MgCl2 and CaCl2 water types which could
reflect the marine water origin. However, the Cl/(Na + K)
> 1 shows that the marine genesis of MgCl2 type.
The existing salt combinations of MgCl2 water genesis
reflects the appearance of Ca (HCO3)2 as salt of tempo-
rary hardness that is may be due to the nearby of the
MgCl2 zone to the Na2SO4 water origin zone (Figure 10)
that is greatly affected by the water quality or by the
shallow depth of the present groundwater. On the other
hand, the Ca (HCO3)2 as temporary salt is of limited oc-
currence within the salt combinations of CaCl2 water
origin. A complete disappearance of Mg(HCO3)2 as a
temporary hardness salt could be attributed to the small
equivalent percentage of CaSO4 that exists [22]. Both
CaCl2 and MgCl2 water geneses show that the dominant
salts of permanent hardness are MgSO4 and CaSO4 that
might reflect the influence of leaching processes on the
evaporite deposits that rich in calcium and magnesium
sulfates within the lithologic constituents of the water
bearing formations.
4.2.6. Lateral Hydrogeochemical Variation
In order to study the geographical changes in the chemi-
cal compositions of groundwater within the studied area,
three different hydrochemical cross-sections were con-
structed. Along these sections, the existing structures re-
presented by faulting and folding reveal their impact in
the form of different water genesis within the aquifer.
The cross section (A-A’) that extends NW-SE (Figure
11) showed that the chemical change in water genesis
reveals the occurrence of contiguous different water ge-
nesis starting at southeast by CaCl2 type existing in water
wells 49 & 33. The neighbored aquifer toward the north-
west indicates groundwater of terrestrial Na2SO4 genesis
(Wells No. 47 & 13).The existence of those distinct wa-
ter types, where each one preserves its definite charac-
teristics may declare the discontinuity between them
through probable existing faults.
The aquifer with CaCl2 marine water genesis (Wells
No. 49 & 2) along the profile (B-B’), which is extending
SW-NE (Figure 12), is bounded from northeast by
MgCl2 of marine water genesis (Wells No. 20 & 27). The
existence of both exchangeable MgCl2 and CaCl2 marine
water genesis give evidence about the effect of both
geologic structures particularly the faulting and the high
variable lithofacies of water-bearing formations in the
prevailing of such exchangeable water origin through the
same aquifer.
The third hydrochemical cross-section (C-C’) that ex-
tended SE-NW (Figure 13) passes through water Wells
No. 27, 54 & 13 trending in SE-NW direction. These
wells lie within aquifer zone indicating MgCl2 and Na2SO4
water genesis. This variation in groundwater origin may

A. MURAD ET AL. 419
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2672000
CaCl2 zone
MgCl 2 zone
MgCl2 zone
Na2SO4 zone
Na2SO4 zone
N
a2SO4 zone
MgCl2 zone
MgCl2 zoneCaCl2 zone
CaCl2 zone
CaCl2 zone
MgCl2 zone
Na2SO4 zone
N
Figure 10. Water genesis zonation map for the study area.
greatly reflect the depth that apart from the main re-
charge source and the nature of the excessive pumping
from the groundwater wells that lies close to Jabal Hafit
zone. However, Na2SO4 water genesis indicates shallow
depths and the groundwater connection with the atmos-
phere while that the MgCl2 reveals the impact of over
pumping within the wells neighboring to Jabel Hafit zone
as well as the leaching process of the leachable forma-
tions such as clay and evaporite rocks that form the ma-
jor constitutes of the aquifer.
4.2.7. Groundwater Utilities
The suitability of groundwater in the study area for do-
mestic and agricultural purposes is evaluated. Usually,
water applied for domestic purposes has certain standard
specification as regards to its physical, chemical and

A. MURAD ET AL. 420
Figure 11. Hydrochemical cross section (A-A’). The inset map showing the location of the cross section.
Figure 12. Hydrochemical cross section (B-B’). Inset map showing the location of the cross section.

A. MURAD ET AL. 421
Figure 13. Hydrochemical cross section (C-C’). Inset map showing the location of the cross section.
biological properties. These standards are intended pri-
marily to protect human health. However, the groundwa-
ter in the study area is not suitable for drinking purposes
due to the high TDS values. The suitability of ground-
water in the study area for agriculture practices is as-
sessed using Sodium Adsorption Ratio (SAR) values [23].
The SAR ranged between 1.3 in north-east Mubazarah
(Well No. 25) and 28.18 at Mubazarah (Well No. 18)
(Figure 14). Groundwater in Neima is characterized by
limited harmful effect on plants in the north to a moder-
ate harmful effect for plants in the south. In Ain Bu Suk-
hanah, groundwater can cause moderate to high harmful
effects for plants. Finally, Mubazarah is characterized by
groundwater with high to very high damaging risk if it
used for irrigation.
5. Conclusions
The total dissolved content of the groundwater shows a
general increasing trend from east to west of the northern
Jabal Hafit in Al-Ain area in the eastern part of Abu
Dhabi Emirate, UAE. An area of high TDS content is
encountered in Ain Bu Sukhanah west from Jabal Hafit.
This increase of TDS is attributed to the brine moving
upward near Ain Bu Sukhanah and the existence of sab-
khas in areas of low elevation west of Jabal Hafit. The
sequence of major cations and anions dominance in ground-
water in the study area have the order of: Na+ > Ca2+ >
Mg2+ > K+ and Cl– > 4 SO > 3 respectively.
According to the measured EC and calculated SAR va-
lues, groundwater in Neima is characterized by limited
harmful effect on plants in the north to a moderate harm-
ful effect for plants in the south. The groundwater of Ain
Bu Sukhanah can cause moderate to high harmful effects
for plants. Mubazarah is characterized by groundwater
with high to very high damaging risk if it used for irriga-
tion.
22
HCO 
Brackish groundwater was used for agriculture activi-
ties in the region as it is clear from a positive relationship
between chloride and sodium concentrations. In addition,
high concentrations of chloride in groundwater in Muba-
zarah and Neima areas might be related to the entrapped
saline water within the limestone sequence of Jabal Hafit,
or it can be the agricultural activities from the positive
relationship between Cl and Br. High sulphate concentra-

A. MURAD ET AL. 422
0
10
18
26
40
367000 368000369000 37000037100
0
37200
0
37300
0
37400
0
37500
0
2661000
2662000
2663000
2664000
2665000
2666000
2667000
2668000
2669000
2670000
2671000
2672000
2673000
367000 368000369000 37000037100
0
37200
0
37300
0
37400
0
37500
0
2661000
2662000
2663000
2664000
2665000
2666000
2667000
2668000
2669000
2670000
2671000
2672000
2673000
12
34
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
45
46
47
48
49
50
51
52
53
54
55
56
WELL
ROADS
GREEN AREAS
OUTCROP
N
Figure 14. Distribution map of the SAR in the study area.
tions in groundwater might be related to the presence of
gypsum and anhydrite within the limestone sequence of
Jabal Hafit. The presence of bicarbonate and sulphate
may indicate mixing process of groundwater by the re-
cent freshwater through the structural lineaments within
the study area. The predominance of sulphate anion con-
centration within Cl-sulphate group could be attributed to
the depth and distance from the catchment area as well as
the leaching processes of the evaporitic rock constituents.
The hydrochemical parameters indicte a relative increase
in the concentration of calcium, magnesium and sulphate
ions which might indicate the influence of water-bearing
formations of carbonates and evaporite sediments. The
chemical analyses also indicated that the Na2SO4 is of
deep percolation, while NaHCO3 is of surface and sallow
meteoric water conditions.
6. Acknowledgements
The investigators would like to express their sincere ap-
preciation to the United Arab Emirates University for the
financial support of this study. The investigators would
also like to express their gratitude to Mr. Hamdi Kandil
for drafting Fi gu re 1 of this manuscript.
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A. MURAD ET AL. 423
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A. MURAD ET AL. 424
Appendix
Serial No. ID TDS (ppm)Units Chemical analysis represented as mg/l, meq/l, meg%
K+ Na+ Ca2+ Mg2+ Cl-
2
4
SO 
3
HCO

5740 ppm 465.0 1584.9 565.7 157.0 3089 495 111.8
meq/l 11.89 68.94 28.23 12.92 87.13 10.31 1.83 1 GW-1
meq% 10% 57% 23% 11% 88% 10% 2%
7520 ppm 77.6 2214.0 668.9 196.8 4130 841 120
meq/l 1.98 96.3 33.38 16.19 116.49 17.52 1.97 2 GW-2
meq% 1% 65% 23% 11% 86% 13% 1%
6840 ppm 74.1 1933.0 673.9 176.1 4494 690.5 109.8
meq/l 1.9 84.08 33.63 14.49 126.76 14.39 1.8 3 GW-3
meq% 1% 63% 25% 11% 89% 10% 1%
6060 ppm 63.7 1677.9 600.3 142.3 3755 528.8 109.8
meq/l 1.63 72.98 29.96 11.71 105.92 11.02 1.8 4 GW-4
meq% 1% 63% 26% 10% 89% 9% 2%
9770 ppm 97.2 2745.6 777.1 265.2 5480 1418 122
meq/l 2.49 119.43 38.78 21.82 154.57 29.54 2 5 GW-5
meq% 1% 65% 21% 12% 83% 16% 1%
8450 ppm 80.9 2219.5 701.1 245.3 6212 1471 122
meq/l 2.07 96.54 34.99 20.19 175.22 30.65 2 6 GW-6
meq% 1% 63% 23% 13% 84% 15% 1%
5020 ppm 71.6 1686.9 299.3 323.4 1811 3512 337.5
meq/l 1.83 73.38 14.94 26.61 51.08 73.17 5.53 7 GW-7
meq% 2% 63% 13% 23% 39% 56% 4%
2050 ppm 26.3 477.5 150.9 232.7 444 1171 252.1
meq/l 0.67 20.77 7.53 19.15 12.52 24.4 4.13 8 GW-8
meq% 1% 43% 16% 40% 30% 59% 10%
1910 ppm 29.8 515.6 155.4 258.6 430 1001 276.5
meq/l 0.76 22.43 7.75 21.28 12.13 20.85 4.53 9 GW-9
meq% 1% 43% 15% 41% 32% 56% 12%

A. MURAD ET AL. 425
Continued
2280 ppm 25.7 424.5 123.3 219.9 558 1346 268.4
meq/l 0.66 18.46 6.15 18.1 15.74 28.04 4.4 10 GW-10
meq% 2% 43% 14% 42% 33% 58% 9%
4240 ppm 49.0 1110.7 352.9 398.9 1192 2250 317.2
meq/l 1.25 48.31 17.61 32.82 33.62 46.88 5.2 11 GW-11
meq% 1% 48% 18% 33% 39% 55% 6%
3790 ppm 48.3 914.7 351.3 392.0 976 2298 317.2
meq/l 1.24 39.79 17.53 32.26 27.53 47.88 5.2 12 GW-12
meq% 1% 44% 19% 36% 34% 59% 6%
2530 ppm 28.3 480.4 150.4 239.3 615 1382 290.8
meq/l 0.72 20.9 7.51 19.69 17.35 28.79 4.77 13 GW-13
meq% 1% 43% 15% 40% 34% 57% 9%
2250 ppm 32.7 588.8 203.6 276.7 492 1084 292.8
meq/l 0.84 25.61 10.16 22.77 13.88 22.58 4.8 14 GW-14
meq% 1% 43% 17% 38% 34% 55% 12%
3080 ppm 389.0 726.4 261.7 329.7 492 1084 292.8
meq/l 9.95 31.6 13.06 27.13 20.31 35.5 5 15 GW-15
meq% 12% 39% 16% 33% 33% 58% 8%
13700 ppm 107.3 4113.9 988.0 427.9 7198 2315 154.5
meq/l 2.74 178.94 49.3 35.21 203 48.2 2.53 16 GW-16
meq% 1% 67% 19% 13% 80% 19% 1%
6940 ppm 43.8 1685.0 522.3 191.2 3110 698 113.9
meq/l 1.12 73.29 26.06 15.73 87.72 14.54 1.87 17 GW-17
meq% 1% 63% 22% 14% 84% 14% 2%
14800 ppm 105.5 4335.6 981.4 493.1 7130 2620 150.5
meq/l 2.7 188.59 48.97 40.58 201.1 54.6 2.47 18 GW-18
meq% 1% 67% 17% 14% 78% 21% 1%
4050 ppm 42.1 1389.8 520.86 120.3 2416 498 113.9
meq/l 1.08 60.45 25.99 9.9 68.15 10.38 1.87 19 GW-19
meq% 1% 62% 27% 10% 85% 13% 2%
7760 ppm 60.5 2110.0 665.4 213.3 3550 931 126.1
meq/l 1.55 91.78 33.21 17.55 100.13 19.4 2.07 20 GW-20
meq% 1% 64% 23% 12% 82% 16% 2%

A. MURAD ET AL. 426
Continued
5780 ppm 59.6 1424.1 507.9 156.6 2975 571.5 101.7
meq/l 1.52 61.94 25.35 12.89 83.91 11.91 1.67 21 GW-21
meq% 1% 61% 25% 13% 86% 12% 2%
5720 ppm 54.5 1432.0 497.8 150.5 2895 533.5 105.7
meq/l 1.39 62.29 24.84 12.38 81.66 11.11 1.73 22 GW-22
meq% 1% 62% 25% 12% 86% 12% 2%
5720 ppm 54.5 1432.0 497.8 150.5 2895 533.5 105.7
meq/l 1.56 63.69 27.19 12.64 75.45 11.33 1.87 23 GW-23
meq% 1% 61% 26% 12% 85% 13% 2%
5590 ppm 61.1 1464.2 544.9 153.6 2675 544 113.9
meq/l 1.55 61.61 28.67 12.25 84.58 11.83 1.87 24 GW-24
meq% 1% 59% 28% 12% 86% 12% 2%
5330 ppm 60.5 1416.4 574.6 148.9 2998.5 568 113.9
meq/l 1.65 5.99 29.16 11.82 79.82 11.6 1.87 25 GW-25
meq% 3% 12% 60% 24% 86% 12% 2%
5970 ppm 61.4 1607.1 618.2 158.7 2830 557 113.9
meq/l 1.57 69.91 30.85 13.06 84.55 13.2 1.87 26 GW-26
meq% 1% 61% 27% 11% 85% 13% 2%
6450 ppm 68.3 1706.0 627.5 187.2 3205 705 122
meq/l 1.75 74.21 31.31 15.4 90.4 14.7 2 27 GW-27
meq% 1% 60% 26% 13% 84% 14% 2%
4520 ppm 51.7 1009.5 439.1 587.0 1003 3371 378.2
meq/l 1.32 43.91 21.91 48.3 28.29 70.23 6.2 28 GW-28
meq% 1% 38% 19% 42% 27% 67% 6%
3850 ppm 48.0 839.6 324.3 434.1 1003 3371 378.2
meq/l 1.23 36.52 16.18 35.72 23.83 58.52 5.53 29 GW-29
meq% 1% 41% 18% 40% 27% 67% 6%
5090 ppm 61.5 1196.9 479.8 588.0 1305 4190 325.3
meq/l 1.57 52.06 23.94 48.39 36.81 87.29 5.33 30 GW-30
meq% 1% 41% 19% 38% 28% 67% 4%

A. MURAD ET AL. 427
Continued
2160 ppm 32.8 386.5 250.8 250.6 500 1835 260.3
meq/l 0.84 16.81 12.52 20.62 14.1 38.23 4.27 31 GW-31
meq% 2% 33% 25% 41% 25% 68% 8%
4340 ppm 51.9 858.2 367.7 476.4 900 2810 317.2
meq/l 1.33 37.33 18.35 39.2 25.39 58.54 5.2 32 GW-32
meq% 1% 39% 19% 41% 28% 66% 6%
8470 ppm 63.2 2275.4 866.5 269.8 4999 1712 235.9
meq/l 1.62 98.97 43.24 22.2 141 35.6 3.87 33 GW-33
meq% 1% 60% 26% 13% 78% 20% 2%
17400 ppm 179.5 4927.3 1812.8 673.7 9420 1746 142.3
meq/l 4.59 214.33 90.46 55.44 265.71 36.38 2.33 34 GW-34
meq% 1% 59% 25% 15% 87% 12% 1%
7490 ppm 124.9 3824.8 1764.4 443.8 3140 6280 122
meq/l 3.19 166.37 88.05 36.52 88.57 131 2 35 GW-35
meq% 1% 57% 30% 12% 40% 59% 1%
15200 ppm 131.3 4116.0 1650.9 543.5 9995 1415 211.5
meq/l 3.36 179.04 82.38 44.72 281.9 282 3.47
36 GW-36
meq% 1% 58% 27% 14% 50% 50% 1%
12300 ppm 115.1 3698.2 1318.3 434.9 4970 1960 93.53
meq/l 2.94 160.86 65.79 35.79 140.19 40.83 1.53 37 GW-37
meq% 1% 61% 25% 13% 77% 22% 1%
17200 ppm 1656.8 4953.5 1676.3 5172.8 10000 1930 207.4
meq/l 42.38 215.47 83.65 425.66 282.07 40.21 3.4 38 GW-38
meq% 6% 28% 11% 55% 87% 12% 1%
13700 ppm 131.6 4218.0 1502.0 4829.1 7798 1687 178.9
meq/l 3.37 183.47 74.95 397.38 219.96 35.15 2.93 39 GW-39
meq% 1% 28% 11% 60% 85% 14% 1%
7110 ppm 79.0 2633.8 300.9 364.4 2385 3990 353.8
meq/l 2.02 114.56 15.02 29.99 67.27 83.13 5.8 40 GW-40
meq% 1% 71% 9% 19% 43% 53% 4%

A. MURAD ET AL. 428
Continued
7470 ppm 99.1 2114.2 968.9 247.2 4485 825 89.47
meq/l 2.53 91.96 48.35 20.34 126.51 17.19 1.47 41 GW-41
meq% 2% 56% 30% 12% 87% 12% 1%
7460 ppm 97.2 2129.3 970.8 251.1 4010 911 105.7
meq/l 2.49 92.62 48.45 20.66 113.11 18.98 1.73 42 GW-42
meq% 2% 56% 30% 13% 85% 14% 1%
8810 ppm 122.3 2822.7 942.0 325.3 4610 2130 183
meq/l 3.13 122.78 47.01 26.77 130.03 44.38 3 43 GW-43
meq% 2% 61% 24% 13% 73% 25% 2%
7490 ppm 97.8 2192.9 900.7 266.7 3500 1750 187.1
meq/l 2.5 95.39 44.95 21.95 98.72 36.5 3.07 44 GW-44
meq% 2% 58% 27% 13% 71% 26% 2%
8090 ppm 96.9 2322.3 877.2 284.7 4580 1420 65.07
meq/l 2.48 101.01 43.77 23.43 129.2 29.6 1.07
45 GW-45
meq% 1% 59% 26% 14% 81% 19% 1%
3210 ppm 79.4 1123.5 131.8 187.4 1130 2430 471.7
meq/l 2.03 48.87 6.58 15.42 31.87 50.63 7.73 46 GW-46
meq% 3% 67% 9% 21% 35% 56% 9%
2760 ppm 67.6 879.8 110.7 190.9 860 940 520.5
meq/l 1.73 38.27 5.52 15.71 24.26 19.58 8.53 47 GW-47
meq% 3% 63% 9% 26% 46% 37% 16%
6770 ppm 89.6 1846.4 840.0 213.0 3715 770 105.7
meq/l 2.29 80.31 41.92 17.53 104.79 16.04 1.73 48 GW-48
meq% 2% 57% 30% 12% 86% 13% 1%
7070 ppm 87.5 1826.5 842.4 218.2 3725 825 105.7
meq/l 2.24 79.45 42.04 17.96 105.07 17.19 1.73 49 GW-49
meq% 2% 56% 30% 13% 85% 14% 1%
8000 ppm 107.9 2405.0 668.8 338.7 3150 1815 248.1
meq/l 2.76 104.61 33.37 27.87 88.85 37.81 4.07 50 GW-50
meq% 2% 62% 20% 17% 68% 29% 3%

A. MURAD ET AL. 429
Continued
3010 ppm 41.8 580.2 756.3 336.2 620 3085 203.3
meq/l 1.07 25.24 37.74 27.67 17.49 64.27 3.33 51 GW-51
meq% 1% 28% 41% 30% 21% 76% 4%
3360 ppm 53.8 885.8 486.6 219.7 1195 3040 248.1
meq/l 1.38 38.53 24.28 18.08 33.71 63.33 4.07 52 GW-52
meq% 2% 47% 30% 22% 33% 63% 4%
3410 ppm 69.8 1097.4 160.7 196.7 1166 1948 390.4
meq/l 1.79 47.73 8.02 16.19 32.89 40.6 6.4 53 GW-53
meq% 2% 65% 11% 22% 41% 51% 8%
2660 ppm 47.8 743.3 332.9 179.6 722 1836 252.1
meq/l 1.22 32.33 16.61 14.78 20.37 38.3 4.13 54 GW-54
meq% 2% 50% 26% 23% 32% 61% 7%
11500 ppm 152.9 3595.4 1244.1 415.8 4060 1465 89.47
meq/l 3.91 156.39 62.08 34.22 114.52 30.52 1.47 55 GW-55
meq% 2% 61% 24% 13% 78% 21% 1%
6920 ppm 90.7 2076.1 823.7 259.2 3800 1100 113.9
meq/l 2.32 90.31 41.1 21.33 107.19 22.92 1.87 56 GW-56
meq% 1% 58% 27% 14% 81% 17% 1%