1. GEOCHEMISTRY OF SULPHATE-BEARING WATER OF AKRA
KAUR DAM, GWADAR, BALOCHISTAN AND ITS ASSESSMENT
FOR DRINKING AND IRRIGATION PURPOSES
A RESEARCH STUDY BY GEOLOGIST PAZEER UNDER SUPERVISION OF
PROF.DR.SHAHID NASEEM, UNIVERSITY OF KARACHI. ACCEPTED AND
PROCESSING FOR INTERNATIONAL PUBLICATION BY EUROPEAN JOURNAL
OF EARTH SCIENCE “ENVIRONMENTAL GEOLOGY”

2. GEOCHEMISTRY OF SULPHATE-BEARING WATER OF AKRA
KAUR DAM, GWADAR, BALOCHISTAN AND ITS ASSESSMENT
FOR DRINKING AND IRRIGATION PURPOSES
A RESEARCH STUDY BY GEOLOGIST PAZEER UNDER SUPERVISION OF
PROF.DR.SHAHID NASEEM, UNIVERSITY OF KARACHI. ACCEPTED AND
PROCESSING FOR INTERNATIONAL PUBLICATION BY EUROPEAN JOURNAL
OF EARTH SCIENCE “ENVIRONMENTAL GEOLOGY”

3. SINDH
IRAN
AFGHANISTAN
Study Area
MAP OF BALOCHISTAN
ARABIAN SEA

4. 10km
Gwadar
Study Area

5. Akra Kaur Dam

11. Spill Way1 3
6
8
10
11
9
4
5
7
2
Sample Sites

12. 62o
10′ 62o
15′62o
05′ 62o
20′ 62o
25′
25o
10′
25o
15′
25o
20′
25o
25′
25o
05′
Pishukan
Gwadar East Bay
Gwadar West Bay
ARABIAN SEA
GWADAR
1493
ARABIAN SEA
Akra Kaur Dam
Chatti
Akra
AkraKaur
GattiKaur
GarriKaur
Parkini
Chatti
Talar
Ormara
Jiwani
FORMATION
L. Miocene
Pliocene
Pleistocene
TERTIARY
4000
4000
AGE DESCRIPTIONS
Mudstone, sandstone and marl.
Limestone, sandstone and conglomerate.100ft
Mudstone, siltstone and sandstone.
Sandy clay with minor conglomerate.3000
Sandstone, shale and mudstone.
E. Miocene
SubrecentHolocene
Plio-Pleistocene
5°
8000
TH.
5°
5°
5°
5°
5°
346
Toshdan
25°
20°
20°
40°35°
10°
25°
40°
25°
35°
Gar-I-Kuh
40°
30°
15°
5°
5°
5°
10°
10° 10°
5°5°
5°
5°
10°
1344
Jabal-I-Mehdi
5km
HighwayM
akranCoastal
Geological
Map of the
study area

13. 1. Composition
2. Genesis
3. Drinking Water Quality
4. Irrigation Water Quality

15. (epm /l)
(mg/l)
74.5
7.8
66.3
5.5
55.5
262
32.7
5.4
3.7
0.6
2.8
.
0.1
.
1
10
100
K ClNaMgCa HCO33SO44
Schoeller diagram

16. Na+K
Ca
Mg
Cl-
HCO3
+
+CO3
2+
SO4
2-
01 1 2 3 4 5 6234
Cations Anionsmeq/l

17. Ca-type
Na+K-
type
Mg-type
Mix-type
Cations
Ca
Mg
CO3+
HCO3 type Cl-type
SO4-type
Mix-type
Anions
Na+K
CO
3+HCO
3
SO4SO
4+Cl
Cl
Ca+Mg
Seawater
Piper diagram
Study area

18. Parameter Min Max Mean
pH 7.05 7.88 7.55
TDS (mg/l) 505 540 522
EC dS/cm 0.79 0.84 0.82
TH (mg/l) 205 235 218
Na (mg/l) 65 70 66
K (mg/l) 5.3 5.7 5.5
Ca (mg/l) 72 78 75
Mg (mg/l) 5 13 8
HCO3 (mg/l) 24 36 33
Cl (mg/l) 49 60 56
SO4 (mg/l) 244 275 262
IBE (%) 0.02 4.64 2.09
RSC 0.09 0.16 0.14
Na % 38.05 41.81 39.06
SAR 1.90 2.12 1.95
PI 47.93 54.16 50.50
MC 9.53 23.43 14.61
KR 0.63 0.74 0.66
CAI 1 -1.16 -0.76 -0.94
CAI 2 -0.26 -0.20 -0.24
CR 16.04 26.70 19.56

20. 0.01
Ca+Mg/ Na+K (emp)
1 10 1000.1
Cl/SO4(emp)
AKD water
(n = 11)
0.1
1
10
Seawater
High SO4 water

21. 0.01
0.1
1
10
0 1 2 3 4 5
Log Cl (mg/l)
Log(Ca+Mg)/(Na+K)epm
SeawaterMixing
water
Freshwater

22. 0 0.2 1.20.4 0.6 0.8 1.0
Na+K/Na+K+Ca (emp)
TDS(mg/l)
1
10
100
10,000
1,000
Precipitation
Rock
dominance
Evaporation
0 0.2 1.20.4 0.6 0.8 1.0
Cl/Cl+HCO3 (emp)
TDS(mg/l)
1
10
100
10,000
1,000
Rock
dominance
Evaporation
Precipitation
AKD water
(n = 11)
AKD water
(n = 11)

23. -2
-1.5
-1
-0.5
0
0.5
1
-1.5 -1.0 -0.5 0.0 0.5 1.0
SI Calcite
SIGypsum
Gypsum &
Calcite
saturated
Gypsum
unsaturated
Calcite
saturated
Gypsum
saturated
Calcite
unsaturated
Gypsum &
Calcite
unsaturated

24. Formation Gypsum Sulphate Contribution of SO4 ion in the water
Ormara 0.66% 0.37% 3,700 mg/kg of rock
Chatti 0.32% 0.18% 1,800 mg/kg of rock
Talar 0.48% 0.27% 2,700 mg/kg of rock
Impact of Geological Formations in
Contributing SO4 ions in the
Akra Kaur Dam Water

27. 74.5 66.3
55.5
262
32.7
600
1
10
100
K ClNaMgCa HCO3SO4
mg/l
500
60060012200150200
200 30025010503075
Desirable limit
Permissible limit

28. High Sulphate
Water

30. 0
5
10
15
20
25
30
35
40
45
50
0 0.5 1 1.5
EC (dS/cm)
Na(%)
Excellent
Good
Fair

31. C1 C2 C3 C4
SALINITY HAZARD
10
20
30
0.250.10 0.75 2.25
EC (dS/cm at 25o
C)
S1
S2
S3
S4
SODIUMHAZARD
SAR

32. Parameters Present Study Harmful above
Bicarbonate 24 36 33 >100mg/l sodium percent (Na%) 38.05 to 41.80 with
an av. 39.06%. >60

33. CONCLUSIONS
Reservoir water of Akra Kaur Dam, Gwadar is analyzed to study geochemical
processes operative in the area and to asses its quality for drinking and irrigation
purposes. The TDS and Cl infer that the samples are of fresh water. The average
ionic composition of the AKD water demonstrate SO4>Ca>Na>Cl>HCO3>Mg>K
showing imbalance in ionic composition. It appears on Piper Diagram as Ca-Mg-SO4
facies type water, close to gypsum dissociation field. The Ca/SO4 and Ca/Mg ratios
of AKD water also indicate influence of gypsum dissolution. The plots of studied
samples on Gibbs diagram further supports influence of rock weathering. The
negative ratio of Chloro-alkaline Indices indicates reverse exchange between Ca and
Mg in water occurred with Na and K in rocks.
The pH, TDS and other major ions are within the permissible limit of WHO
drinking water standards. However, Mg, K, Cl and HCO3 are low and Na and SO4
values are slightly higher than the maximum desirable limit. The investigated
irrigation parameters; RSC, Na%, SAR, PI, MC and KR indicates that the AKD water
is good for irrigation purpose.
It is concluded from the present study that the water of AKD is undersaturated
with respect to gypsum and calcite; shows affinity for further dissolution of gypsum in
next drought season and as a result more SO4 can be concentrated in the water.
The high SO4 content may cause agricultural and health hazards for the inhabitants
of the area.