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fowzia@alsakhriconsult.com Dr. Fowzia Abdullah Geology of the Arabian Gulf and Failaka Island-Review
Petroleum Geology Consultant
ALNAFT ALSAKHRI consultancy
Geology of the ranges in thickness be- stones that are slightly ce-
Arabian Gulf tween 2.4 and 9.8 m. It is mented by calcite. There is
extensively fractured and thin laminated shale with
13 has many chertified dolomi- few green clay beds. They
critic beds and chert bands. were deposited in marine
The unconformity surface and terrestrial environment.
underlies the whole Kuwait. The maximum thickness of
It is a water aquifer with us- Ghar Formation is around
able groundwater. The wa- 180 m.
ter salinity varies from
brackish )2500 ppm( in the The Lower Fars Formation
southwest to brine )150,000 )Middle Miocene( overlies
ppm( in north-eastern Ku- the Ghar Formation and
wait )Omar et al., 1981(. It is consists of fine sandstone,
the most productive water conglomeratic sandstone
aquifer with secondary ef- shale with thin fossiliferous
fective porosity related to limestone mixed with some
faulting, karstification and anhydrite and, gypsum. It
dolomitization )Omar et has repeated fining upward
al.,1981(. cycles reflecting oscillations
in sea level. These rocks
Kuwait Group, Neogene were deposited in fluvio-del-
age, is compose of three taic complex )Ferdous et
formations )Fig 2-D( with a al., 2012( and are exposed
maximum thickness of 516 at Jal Az-zor with an aver-
m. The oldest Ghar Forma- age thickness of 38 m. The
tion lies above the Dam- clay balls locally found in
mam Formation and is ex- sandstones indicate possi-
posed at the foot of Jal ble erosional surface. The
Az-zor. This formation is formation is one of Kuwait
composed of current oil reservoir with heavy oil
cross-bedded coarse sand- type production.
