Kuwait is located in the northwest corner of the
Arabian Gulf between 28°30’ and 30° north latitude and
46°30’ to 48°30’ east longitude. It is approximately 10,700
square miles (17,818 km2) in area; the extreme north-south
distance is 120 miles (200 km), the east-west distance is 100
miles (170 km). To the south it shares a border with Saudi
Arabia; to the west and north, it shares a border with Iraq.
The climate of Kuwait is semiarid and is characterized by two
seasons: a long, hot and humid summer, and a short cold winter.
Summer temperatures range at 84.2°F–113°F (29°C–45°C)
with relatively high humidity. The prevailing shamal winds
from the northwest bring severe dust storms and sandstorms
from June to early August with gusts up to 60 miles per hour
(100 km/hr). Winter temperatures range at 46.4°F–64.4°F
(8°C–18°C). Occasionally, there are simoan winds from the
southwest during the month of November. Annual precipitation
averages 4.5 inches (115 mm) and infiltrates the sandy soil
very rapidly, leaving no surface water except in very few
depressions. Most of the limited rainfall occurs in sudden
squalls during the winter season.
Most of Kuwait is a flat, sandy desert. There is a gradual
decrease in elevation from an extreme of 980 feet (300 m) in
the southwest near Shigaya to sea level. The southeast is generally
lower than the northwest. There are no mountains or
rivers. The country can be divided into roughly two parts,
including a hard, flat stone desert in the north with shallow
depressions and low hills running northeast to southwest.
The principal hills in the north are Jal al-Zor (475 feet; 145
m) and the Liyah ridge. Jal al-Zor runs parallel to the northern
coast of Kuwait Bay for a distance of 35 miles (60 km).
The southern region is a treeless plain covered by sand. The
Ahmadi Hills (400 feet; 125 m) are the sole exception to the
flat terrain. Along the western border with Iraq lies Wadi Al-
Batin, one of the few valleys in Kuwait. The only other valley
of note is Ash Shaqq, a portion of which lies within the
southern reaches of the country. Small playas, or enclosed
basins, are covered intermittently with water. During the
rainy season they may be covered with dense vegetation; during
the dry season they are often devoid of all vegetation.
Most playas range 650–985 feet (200–300 m) in length, with
depths at 16–50 feet (5–15 m).
There are few sand dunes in Kuwait, occurring mainly
near Umm Al-Neqqa and Al-Huwaimiliyah. The dunes at
Umm Al-Neqqa are crescent-shaped or barchan dunes with
an average width of 550 feet (170 m) and average height of
25 feet (8 m). Those near Al-Huwaimiliyah are smaller, averaging
65 feet (20 m) wide and 7 feet (2 m) in height, and are
clustered into longitudinal dune belts. Both mobile and stable
sand sheets occur in Kuwait. A major mobile sand belt crosses
Kuwait in a northwest to southeast direction, following the
prevailing wind pattern. Smaller sheets occur in the Al-
Huwaimiliyah area, in the Al-Qashaniyah in the northeast,
and in much of the southern region.
During the past few years, overgrazing and an increase
of motor vehicles in the desert have caused great destruction
to the desert vegetation. Stabilized vegetated sheets have
changed to mobile sheets as the protective vegetation is
destroyed. The largest stable sheet occurs at Shugat Al-
Huwaimiliyah. Recently, smaller sheets have begun to develop
at Umm Al-Neqqa and Burgan oil field due to an increase
in desert vegetation resulting from a prohibition of traffic.
Kuwait Bay is a 25-mile (40-km) long indentation of
marshes and lagoons. The coast is mostly sand interspersed
with sabkhas and gravel. Sabkhas are flat, coastal areas of
clay, silt and sand that are often encrusted with salt. The
northern portion of the bay is very shallow, averaging less
than 15 feet (5 m) in depth. This part of the shore consists
mostly of mudflats and sandy beaches. The more southern
portion is relatively deep with a bed of sand and silicic
deposits. Most of the ports are situated in the southern area.
Kuwaiti territory includes 10 islands. Most are covered
by scrub, and a few serve as breeding grounds for birds.
Bubiyan, the largest island measuring approximately 600
square miles (1,000 km2) is a low, level bare piece of land
with mudflats along much of its north and west coasts that
are covered during high tides. It is connected to the mainland
by a concrete causeway. To its north lies Warba, another lowlying
island covered with rough grass and reeds. East of
Kuwait Bay and on the mudflats extending from Bubiyan lie
three islands: Failaka, Miskan, and Doha. Failaka is the only
inhabited island belonging to Kuwait. A small village, located
near an ancient shrine, is set on a 30-foot (9-m) hill at the
northwest point of the island. The rest of the island is flat
with little vegetation. There are a few trees in the center of
the island, and date trees are grown in the village. West of
Kuwait City in the Bay are two islets: Al-Qurain and Umm
Al-Naml. On the south side lie three more small islands:
Qaruh, Kubbar, and Umm Al-Maradim. The last two are surrounded
by reefs on three sides.
Kuwait occupies one of the most petroleum-rich areas in
the world, situated in a structurally simple region on the Arabian
platform in the actively subsiding foreland of the Zagros
Mountains to the north and east. Principal structural features
of Kuwait include two subsurface arches (Kuwait arch and
Dibdibba arch) and the fault-bounded Wadi Al-Batin. Faults
defining Wadi Al-Batin are related to Tertiary extension in the
region. The Kuwait and Dibdibba arches have no geomorphic
expression, whereas the younger Bahra anticline and Ahmadi
ridge have a surface expression and are structurally superimposed
on the Kuwait arch. Major hydrocarbon accumulations
are associated with the Kuwait arch. The stratigraphy of
Kuwait includes a nearly continuous section of Arabian platform
sediments ranging in age from Cambrian through
Holocene, although the pre-Permian rocks are poorly known.
The Permian through Miocene section is 3.5–4 miles (6–7 km)
thick in Kuwait but thickens toward the northeast. These
rocks include continental and shallow marine carbonates,
evaporites, sandstones, siltstones, and shales, with less common
gravels and cherts. Plio-Pleistocene sand and gravel
deposits of the Dibdibba Formation outcrop in northwestern
Kuwait, and Miocene sands, clay and nodular limestone of
the Fars and Ghar Formation outcrop in the southeast. A
small area of Eocene limestone and chert (Dammam Formation)
outcrops south of Kuwait City on the Ahmadi Ridge.
The structural arches in Kuwait are part of a regional set
of north-trending arches known as the Arabian folds, along
which many of the most important oil fields in the Arabian
Gulf are located. These arches are at least mid-Cretaceous in
age. The orientation of the Arabian folds has been interpreted
to be inherited from older structures in the Precambrian basement,
with possible amplification from salt diapirism. The
north-south trends may continue northward beneath the
Mesopotamian basin and the Zagros fold belt.
The northwest-trending anticlinal structures of the
Ahmadi ridge and Bahra anticline are younger than the Arabian
folds and related to the Zagros collision, initiated in
post-Eocene times. These younger folds seem to have a second-
order control on the distribution of hydrocarbon reservoirs
in Kuwait, as oil wells (and since the first Gulf War in
1990, oil lakes) are concentrated in northwest trending belts
across the north-striking Kuwait arch. The Kuwait arch has a
maximum structural relief in the region between Burgan and
Bahra, with closed structural contours around the Wafra,
Burgan, Magwa, and Bahra areas, and a partial closure indicating
a domal structure beneath Kuwait City and Kuwait
Bay. The superposition of the Kuwait arch and the shallow
anticlinal structure of the Ahmadi ridge form a total structural
relief of at least one mile (1.6 km).
The northwest-trending Dibdibba arch represents another
subsurface anticline in western Kuwait. The ridge is
approximately 45 miles (75 km) long and is an isolated
domal structure, but it has not as yet yielded any significant
hydrocarbon reservoirs.
Wadi Al-Batin is a large valley, 4–6 miles (7–10 km)
wide and with relief of up to 185 feet (57 m). In the upper
valley of the wadi, the valley sides are steep, but in southwestern
Kuwait few ravines have steep walls greater than 15
feet (5 m) in height. The wadi has a length of more than 45
miles (75 km) in Kuwait and extends 420 miles (700 km)
southwestward into Saudi Arabia, where it is referred to as
Wadi Ar-Rimah. The ephemeral drainage in the wadi drains
from the southwest and has transported Quaternary and Tertiary
gravels consisting of igneous and metamorphic rock
fragments from the Saudi Arabian and Syrian deserts during
Pleistocene pluvial episodes. The wadi widens toward the
northeast, and it becomes indistinguishable from its surroundings
northwest of Kuwait City. Ridges made of Dibdibba
gravel define paleodrainage patterns of a delta system
draining Wadi Al-Batin, and many of these gravel ridges
stand out as prominent lineaments. Some of these gravel
ridges are marked by faults on at least one side, suggesting a
structural control on the drainage pattern.
Numerous small and several relatively large faults are
revealed on seismic reflection lines across the wadi, and hydrological
pumping tests show a break in the drawdown slope at
the faults. The steep Miocene–late Eocene faults parallel to the
wadi have displaced the block in the center of the wadi
upward by 15–20 feet (25–35 m) relative to the strata outside
the wadi, and the displacements die out toward the northeast.
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