The basic question of geomorphology is “why do landscapes look the way they do? ” As a study of landforms, geomorphology seeks to understand the history and dynamics of landforms development. The landforms change constantly due to physical and chemic interaction between the Earth’s surface and the environment, including influences by geological processes, climate, vegetation, atmospheric processes, erosion by sea waves. In recent years the activities of man took a place of one of the basic factors influencing geomorphology.
In this paper some of the geomorphological processes shall be studied using an example of Kuwait. The final purpose of the paper is to gain general understanding of geomorphological processes taking place in Kuwait and thusly obtain knowledge about the nature of geomorphological processes as they are. First and foremost it is necessary to give a definition of geomorphological process and provide their classification in order to understand what should be considered to be a geomorphological process, and what should not.
Rhodes Fabridge in his “Encyclopedia of Geomorphology” speaks of it as of a science of a scenery and describes geomorphological process as processes contributing to geomorphological changes. They are classified into: 1. Erosional processes, causing erosion of earth materials, including deflation, karst, piping and washing; 2. Fluvial processes caused by behavior of rivers, including braiding and channel processes; 3. Mass movement processes – a movement of surface materials due to gravity, including snow avalanches, slow mass movement and rapid mass movement ;
Periglacial and deglacial processes are also part of natural geomorphological processes, but they shall not be described, because neither of them takes place in Kuwait. However, there is another important group of processes affecting geomorphology – processes caused by human activity. They can result from willful desire to change the landscape, such as drifting or dismantling hills, building dams and artificial islands and they can be accessory result of some other activity, which is often undesirable and harmful. After a brief overview of geomorphologhical processes, we shall now apply this knowledge to Kuwait.
In terms of geomorphology the territory of Kuwait is a flat sandy desert gradually slopping to the sea, with the lowest point of zero above the sea level and the highest point of 306 above the sea level (the location is unnamed) . This landscape is broken by the ridge at Jal Al-Zor – a series of low hills and shallow depressions. The highest point of the ridge is 145 meters above the sea level. The ridge is cut into two by Umm Al-Ramam Wadi. The southern part of Kuwait is flat with exception of Ahmadi hill (137 m) . Eolian processes in Kuwait
Eolian processes are those geomorphological processes, which are caused by wind, including some types of erosional processes. For a desert country the eolian processes are most natural. They can be observed throughout the desert, especially on the south of Kuwait, where winds and sandstorms form the so-called sabkhas – irregular closed lowland areas. Two different types of Sabkhas are recognized: costal sabkhas and inland sabkhas. The costal ones are situated mostly in the Al-Jailaiaha and Al-Khiran areas, being extended along a costal depression. Inland sabkhas are situated in the desert areas of Al-Maqwa, Urafjan, and Al-Gurain.
On the Kuwait’s west both types of sabkhas are subjected to erosional changes after sandstorms when they may be entirely filled with sand and disappear, and new sabkhas may appear. Often sabkhas are movable and change their location after storms . Sabkhas in Kuwait are often surrounded by dunes – another geomorphological form created by eolian processes. Dunes appear when wind transports sand to a particular spot of the landscape, carving out sand from the sabkhas. By their nature dunes are depositional landforms up to 25 meters high. There exist two types of dunes in Kuwait – desert dunes and costal dunes.
Desert dunes are in turn classified into: 1. Barchans – crescent-shaped dunes enlonged in the wind-direction with points (wings) curved downwind creating a slip-face; 2. Barchanoid Ridges – several barchans tied together similarly to a mountain ridge; 3. Transverses – long irregular dunes that form right angles to wind direction and have long slip-face; 4. Parabolic dunes – crescent-shaped dunes with long axis repeating a dominant wind direction 5. Star Dunes – a large mount of sand with several sinuously radiating ridges from a central peak of sand; 6. Dome – round or elliptic dune with no slip-faces.
Coastal dunes are similar to desert ones, but they are formed by strong winds blowing from the sea, often covered with vegetation. The rocky ridges in the deserts of Kuwait are also subjected to another type of eolian processes, namely wind erosion. Winds blowing over the rocks create areas of desert pavements around them – places covered with fragments of rock left after the wind has blown away the fine particles. On the top those areas are covered with desert varnish exposing to the surface. By blowing away soft rock fragment wind forms deflation basins, or minor depressions on the rocky surface.
Where the rocks consisted of soft formations with dikes composed of hard rocks the wind blows the soft rocks away leaving freakish sculptured landforms called yardangs . Yardangs are not numerous in Kuwait and exist mostly in a form of low irregular pillars or peaked low crests . Additionally, rocks are affected by temperature extremes, which can be pretty high – a temperature can change for up to 30o C in one day and up to 50o C within a year. Combined with rains such extremes gradually ruin even the firmest grounds. Coastal processes in Kuwait
Kuwait is washed by waters of Persian Gulf. In the centre of the country it’s coast bends forming the Gulf of Kuwait, where the capital of the country lays. The The coast of Kuwait is divided into nine geomorphological potions, out of which four are lie along the northern muddy shoreline and five in the southern sandy area. The northern part includes large portions of bays, which are filled with water during high tides and for most of the time they are areas of muddy ground. They are limited by costal sabkhas or sandy drifts. Intertidal channels form sandbars near the waterlines .
At the coast the geomorphologic processes are represented by a combination of wind and waves influences. Washing processes result lead to formation of low sandy barriers along coasts, which mark the breaker line. Those barriers are made of sand partials brought by waves and are additionally affected by wind. In the northern portion of Kuwait’s shores piping processes lead to washing away soft rocks and formation of intertidal channels, tying together the sea and large portions of bays, which are filled with water during high tides and being muddy ground of the timed .
In contrast to this, due to a different character of grounds, the southern portion of Kuwait’s coat is known with steep sandy beaches, narrowed by wide rocky intertidal platforms, covered with sand and other sediments, washed ashore by waves. In many places those rocky surfaces are dissected by intertidal channels and shallow gulleys. The low water line is marked by numerous sandbars. Sometimes they are formed in berms by waves . Costal dunes are often covered with vegetation binding sand together and preventing dunes from distruction. Karst processes in Kuwait
Depths of Kuwait are characterized by intensive karst processes. Limestone geological formations, especially in the places where they lay close to surface, collect water from rains and other sediments like dew and this water erodes limestone forming cavities and pore spaces filled with water. Such processes are vital for Kuwait’s economy, because the country depends on them for water. In 1960 a large aquifer has been discovered in the western portion of Ar Rawdatayn geological formation, which is now used for distilled water production, covering most of the country’s needs.
On the south from the city of Kuwait another water field has been discovered in the top of the limestone of the Ash Shuaybah. The water here is salty, so it is used mostly for agricultural and commercial needs. . Unfortunately, the Gulf war caused notable harm to Kuwaiti water supplies in the limestone depths. Exploding almost 700 oil wells caused oil to spill over the desert and in the rocks creating lakes of oil, which were estimated to contain 15 times more oil, than it has been spilled to the Gulf. Large amounts of oil particles are still detected in the sandy and rocky soils of Kuwait .
Another effect of the war was partial destruction of the shoreline by oily spots and burning oil. The vegetation in the coastal areas suffered greatly, and this resulted in ruination of costal dunes and sabkhas. Some of the intertidal channels, especially in the northern part of the country, were littered with oil partials and do not let water pass any longer, causing drying up of minor costal bays and lakes .
Works cited: 1. Rhodes Whitmore Fairbridge. Encyclopedia of Geomorphology, New York: Van Nostrand Reinhold, 1968 2. A. Al-Hurban , and I.Gharib, “Geomorphological and sedimentological characteristics of coastal and inland sabkhas, Southern Kuwait”, Journal of Arid Environments Volume 58, Issue 1, July 2004, Pages 59-85 3. Selby, M. J. Earth’s Changing Surface. Oxford: Oxford University Press, 1995 4. Mohamed I. El-Sayed and Dhia Al-Bakri, “Geomorphology and sedimentary/biosedimentary structures of the intertidal environment along the coast of Kuwait, north-western Arabian Gulf”. International Journal of Earth Sciences. Volume 83, Number 2 / July, 1994 5. Francesca Davis Dipiazza. Kuwait in Pictures, Twenty-First Century Books, 2006
6. J. Al-Sulaimi , M. N. Viswanathan and F. Szekely. “Effect of oil pollution on fresh groundwater in Kuwait”. Environmental Geology, Volume 22, Number 3 / November, 1993, p. -246-256 7. 2007 CIA WORLD FACTBOOK. Kuwait (CD-ROM), Progressive Management, 2006 8. Geomorphological processes. Published by Ministry of Environment of British Columbia. Available at: http://ilmbwww. gov. bc. ca/risc/pubs/teecolo/terclass/geo. htm#anchor800962 (October 19, 2007) 9. The Environment and the 1991 Persian Gulf War available at: http://countrystudies. us/saudi-arabia/17. htm (October 19, 2007)