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1.2 Geomorphology 1.2.1 RELIEF GENERAL CHARACTERISTIC The Greater Caucasus area represents a system of folded ridges, it expressed in coastal line by its south-eastern edge (the South-Eastern Caucasus) and orographically consists of two main lines – Main and Lateral Ridges, between which there are depressions and small longitudinal ridges. The main heights of the South-Eastern Caucasus locate off the shore zone, to the west from it directly. They are: Bazardyuzi Mt (4466 m), Tufan Mt (4191 m), Babadag Mt (3629 m) on the Main ridge and Shakhdag Mt (4243 m), Gizilgaya Mt (3726 m), Yarudag Mt (4116 m) on Lateral Ridge. In the coastal part of the land the following mountains are corresponded to the maximal marks: Kelani Mt (2205 m), Dibrar Mt (1908 m), Varafta Mt (1230 m), Chirahgaya Mt (1221 m), etc. To the north from Lateral Ridge there are low Shudug and Gainarja foothill ridges (to 1900 m above sea level), getting down in the south-eastern direction, on the north successively replaced with Gusar inclined plane and Samur-Devechi lowland directly adjacent to sea shore. On the south slope of the Main Ridge there are ridges. They echelon-like replace each other and fan-like diverge. Their hypsometry comes lower in the south and south-eastern directions from 2000-2500 m to 300-600 m and which orographically joins with wide stripe of foothills – Gobustan and Apsheron peninsula. Lateral and Main Ridges of the Greater Caucasus break off on approaching to Yashma and Apsheron peninsulas, the south-eastern troughs stretch along the coast up to Alyat cape. The Main ridge is a water-division of the South-Eastern Caucasus where the region main rivers begin, they flow down in the northern and southern directions. Lyangyabiz, Greater Kharamin and Alyat ridges are extreme morphostructural elements of the relief on the south, fence the mountain-folded complex of the Greater Caucasus off the Central Aran area. To the last one the eastern part of Kura-Araz lowland, including the South-Eastern Shirvan, Mugan and Salyan steeps, is corresponded there in the coastal zone. Orographically it is a sloping plane with dominating negative height marks (up to 0 m), gently inclined towards Kura river bed and Caspian coast. In the eastern part of the lowland along the meridional part of Kura river there are low (to 100 m) elevations Durovdag, Duzdag, etc. On the south Kura-Araz lowland unaffectedly joins with Lenkaran lowland, narrowly stretching in the southern direction between Caspian Sea shore and steep eastern slopes of Talysh Mountains. It is an eastward gently inclined plane with mainly negative hypsometric marks, cut by numerous sublatitudinal river beds flowing down Talysh Mountains. Talysh Mountains represent a system of folded ridges elongated from the northwest to the southeast. Along the state border with Iran there is Main Talysh Rridge with maximal height marks: Kemyurkei Mt (2493 m), Gizyurdu Mt (2433 m), etc. To the north-south from water-division and subparallel to it Peshtasar (to 2200-2240 m height) and Alashar-Burovar (to 900-1000 m) ridges stretch successively. The typical feature for Talysh Mountains is a great number of cross, typically erosion ridges, cross-pieces, depression. On the north-east the mountains end by low foothills with mainly ridge dissection. 1.2.2 LAND GEOMORPHOLOGICAL CHARACTERISTIC Geomorphologically the coastal zone is divided into the following areas and regions according to scheme of Azerbaijan zonation (Fig. 2):
In its tern each of the mentioned regions consist of some subregions. 1.2.2.1 Samur-Devechi Region Within the land the eastern part of region is basically occupied by Shollar plane, fenced off sea by coastal line of young terraces. On the north it is limited by plane of Samur river, on the west - by Gusar inclined fluvioglacial plane, on the south-west - by Devechi plateau-like upland, and to the south-east it comes into Devechi-Sumgayit alluvial-marine and marine terraced plane being in composition of Pri-Caspian-Apsheron region. Shollar plane is formed by flattened cones of Samur river deposits and numerous rivers flowing down the mountains and bringing to the plane a great deal of loose rocks as well-rounded pebbles. As a result of it there appears gently-wavy and banked relief. On surface the plane is blocked by proluvial-deluvial loams. Near the border with Gusar inclined plane the height of Shollar plane reaches to 200 m (near Samur-Apsheron canal). Gusar inclined fluvioglacial plane locates to the west from Samur-Apsheron canal and represents a surface inclined off the mountains. The surface is cut by numerous rivers, river beds and dry ravines. As a result of such division there appear some gentle banks, and hills which make crossed enough relief together with planes, gullies and ravines. Thus, the application of term "plane" for this relief type is convenient significantly. Gusar inclined plane is composed of shingles and conglomerates representing the fluvioglacial deposits of the Upper Pliocene glacierization. Devechi plateau-like upland stretches from Shabranchai river on the north-west up to Beshbarmak Mt on the south-east. It is confined to Gainarja anticline complicated by mud volcanism of the same name. In the north-eastern and south-eastern parts the upland is complicated by marine terraces covering a vast area. Coastal line of young teracces. In region of Samur river delta and further to the south up to Amiya cape the coastal line is characterized by complete absence of Pre-Quaternary rocks outcrops. The coastal line draws an arc of big radius convex towards the sea and having exclusive straight outlines. Such character of shore must be related with carrying out of great deal of material by numerous rivers flowing down the mountains. A sandy delta weakly going into the sea is observed in Samur river mouth. To the south of Samur river delta in the region of Yalama sea-shore the beach line pinches out gradually and a steep ledge of height from 6-7 m to 13-14 m comes to shore. The ledge is composed of shingles and loams and traceable for 5 km. Further to the south a shore has a wide beach with low shore banks from 0.5 to 1 m height. Drying up lagoons is typical for coastal line. They elongate along the shore line. Beyond the lagoons a young new terrace is observed. To the south-west from the latter a line of dunes is well observed, it consists of 2-3 parallel ridges of dune hills divided by the lowered parts. According to morphological signs the coastal line is subdivided into four sections: Pri-Samur, Yalama, Khachmaz and Agzibir. Pri-Samur section is characterized by accumulative-delta shores and corresponds to the recent delta of Samur river. In spite of great amount of yearly hard flow of river - 7 mln.t., a recent delta of Samur river takes comparatively small area - 300-350 km2. It is due to intensive submersion of the pre-mouth space and expenses of major fragmental material for avandelta construction. Yalama section is confined to ancient delta of Samur river. Due to displacement of the main bed of Samur river to the north, caused by burial of Derbent depression and lack of deposits, the shores are washing out now. Khachmaz section, located between lowlands of Gusarchai and Velvelchai, where the alluvial-proluvial material, brought our by rivers, increases the shores towards the sea. The recent beach is undergone by the eolian influence of the north-eastern winds prevailing here. The sandy material accumulates in coastal line forming the dunes, sandy ridges and uneven ands. Often dunes prevent the flow of rivers into the sea; it is the reason of the lowland swamping. Agzibir section located between the lowlands of Velvelchai and Gilgilchai, is characterized by development of shores of lagoon type. Coastal land is expressed by swamping lowland. There is Agzibir Lake in the central part of this lowland. This lake is lagoon relict existing in this place before. 1.2.2.2 Pri-Caspian-Apsheron Region Pri-Caspian-Apsheron region is confined to the south-eastern submersion of the mountain-folded complex of the Greater Caucasus the complexity of geological structure of which determines the relief complexity as well. In the northern part of the region the coastal line has simple outlines, it follows the main tectonic structures near parallely. Only the area of Gilyazi spit, which the submerged structures of mountain zones pass through, projects into the sea as Yashma peninsula. On Apsheron peninsula projecting into the sea for 73 km, the coastal line cuts the main tectonic directions at obtuse angle, in this connection it has cut outline. Beshbarmag-Kemchi, Pri-Caspian and Apsheron subregions are distinguished on the present territory. Beshbarmag-Kemchi subregion covers low-middle part of the region. Arid-denudation structural mountains and depressions, and also terraced inclined planes are typical for this region. Tengi-Beshbarmak, Begimdag and Main-Caucasian ridges take the northern part of the subregion. Between them there are Keshchai and Tygchai depressions. Ravines, gullies, collapses, landslides, badlands, clayey karst, and also erosion-accumulative terraces are developed in depressions. In the southern part of the subregion there are Gyadin, Kemchi and Kabandag mountain ridges, they are broke down by gullies, ravines and badlands. Inter-ridge spaces are distinctly expressed in relief by denudation-tectonic depressions - Khanagin, Halgyakh, Kabandag and Agrijin. They are broke down by badlend, clayey karst and ravines. Seaside (Devechi-Sumgayit) subregion takes the lower part of the region and expresses an alluvial-marine plane formed by accumulative terraces. Region is characterized by negative sedimentation caused by lack of deposits. Coastal line is subdivided into two sections: Siazan and Gilyazi. Siazan section takes a coastal line between Gilgilchai river mouth and Gilyazi settlement. For the long period of time the shore was abrasive here. Abrasive cliffs outlined the recent beach point to that. Due to sharp change of shore line direction near Siazan town there observed a significant reduction of thickness of along-shore flow of deposits. In past the lack of deposits caused an abrasion of Amiya cape and the southern part of shore. Gilyazi section is a complex abrasive-accumulative form of tombolo type. Banks and outcrops of rocks took part in its formation. Accumulative forms of spit are underlied by ancient benches. This bench's continuation is traced on the underwater slope the highest points of which expressed as underwater and water stone ridges. Apsheron subregion. Orographicaly Apsheron peninsula is the south-eastern continuation of the Greater Caucasus and occupies an area about 2000 km2. On the west this peninsula's border passes conventionally on the meridian of Gilyazi Dili cape (north) and Sangachal cape (south) where it joins with lower-mountain part of Gobustan foothills. According to orographical signs the peninsula is subdivided into four main zones: lower-mountain north-western and south western, northern (or central) hill-ridge plain and the eastern - plain zone. The vast lowers - troughs (Gyuzdek and Baku) are typical for the south-western part of the peninsula. These troughs are composed of limestones and clays. Gyuzdek trough has a cup-like form with steeped structure of slopes. Baku trough has an amphitheater form turned to the south towards Baku Bay. Trough margins are abrupt and terraced somewhere; more lifted parts are the eastern and western sides. The typical feature of Apsheron landscape is numerous salt lakes and saline lands. The recent shore is characterized by wide development of abrasive-accumulative gulf forms and subdivided into three sections: North-Apsheron, Apsheron actually and Shakh-Dili area. North-Apsheron section locates between Sumgayit River mouth and Gakagakh cape. This area is characterized by accumulative-gulf shores with flatten tendency. Vast gulfs with development of accumulative and anticlinal abrasive capes are typical for this area. The modern beach is formed exclusively by wavy bringing of benthonic material. Apsheron section takes a coastal line between Gakagakh and Gyurgan capes on the north-eastern shore and Govsan and Puta capes on the southern shore of Apsheron peninsula as well. This area is characterized by abrasive-accumulative gulf shore. Here, as well as on the previous areas, the alternation of vast synclinal gulfs with anticlinal capes is observed. The gulfs are characterized by accumulation, and capes - by presence of recent abrasive ledges. Shakh-Dili section is located on the south-eastern edge of Apsheron peninsula and characterized by accumulative even shores deposited by streams from both two sides. The coastal plain surface is complicated by flat-bottom saline depressions and eolian forms of relief. The modern beach has a width up to 500 m, shore banks are not observed. 1.2.2.3 Gobustan Region Gobustan region takes the south-eastern periphery of the Greater Caucasus. Low arid-denudational structural mountains are typical for this region. Small ridges corresponded to the brachyanticlines, comb-like and linear anticlines are observed here. Vast depressions are corresponded to the synclines. Syncline plateau takes a significant territory. Badland and clayey karst are widely spread here. One of the relief typical features are mud volcanoes. Series of river terraces is developed in modern valleys of rivers. The erosion processes develop somewhere. There are marine terraces along the coastal line and on mountain slopes outlined the coastal line. Four subregions - North-Eastern, South-Eastern, Central and Western Gobustan - are distinguished within Gobustan region. North-Eastern Gobustan takes a middle and lower stream of Kenda river, plains of Sumgayit and Jangichai rivers. Small ridges and uplifts are typical for the subregion. On their slopes (especially the southern and south-eastern) a badland is often developed there. There is a Shakhdag plateau between Kenda and Jangichai rivers' valleys. Along the valleys there are widened areas and depressions with well flattened bottom. As a rule, the mountains of the South-Eastern Gobustan are corresponded to the synclinal tectonic structures. Great areas are taken by Gyuzdek, Baku, Kergez, Gyulbakht and other plateaus. Plateaus have steep slopes basically characterized by badland development. Some anticlinal folds expressed in relief as mountain ridges. Bottom parts of valleys and depressions are even, but terraced sometimes and cut by ravines and gullies somewhere. In the southern part of the subregion the lowered areas full of salt lakes and salines. Marine terraces are along the shore. The terraces covered with scattered sands and sandy dunes. Jeirankechmez depression, taking a river valley of the same name, is corresponded to the Central Gobustan. Alluvial-proluvial and abrasive-accumulative terraced plains prevail in relief. Somewhere these plains are separated from each other by small ridges and hills stayed in relief. Intensively regressed ravines with depth of 6-10 m cut into the plain. On the north-east the eastern part of Jeirankechmez plain is limited by 100-m ledge. In the sea-side part of the South-Eastern and Central Gobustan a plain stretches along the shore. The plain has an absolute height from -10 to 40 m. Generally, near-shore land is characterized by inversion relief and presence of large cones of mud volcanoes. The land is broken down by some ravines, and directly the shore there are sandy dunes. The modern shore is characterized by development of abrasive-accumulative gulf forms. Puta, Sangachal, Alyat, Pirsaat capes are confined to outcrops of root rocks in anticlinal uplifts arcs and form the abrasive ledge. In vast synclinal gulfs there is a material accumulation in line of modern beaches. Western Gobustan takes the south-eastern edge of Lengebiz ridge, Navagi and Sabatdyuzi depressions and Airantekyan ridge. The ridges corresponded to the anticlinal structures and depressions to the synclinal structures as well. Basically, the mountains are composed of clays, limestones, breccia; the depressions - of alluvial-proluvial deposits as well. 1.2.2.4 South-Eastern Shirvan Region The South-Eastern Shirvan rlocates in the extreme eastern part of Kura-Araz lowland, it can be subdivided into two geomorphological subregions: eastern submountain and western lowland. Submountain subregion expresses an inclined plain located along the Gobustan foothills. Together with deluvial processes the proluvial (ravine deposits) took part in this plain formation. The proluvial processes make the inclined plain a wavy. On the south-east of the submountain subregion there is a cone of Pirsaat river deposits distinguished there; it is gently and plain enough, complicated only by flat, poor observed inter-comb depressions. The feature of the submountain inclined plain are small uplifts representing the brachyanticlines and mud volcanic cones expressed in relief. Their slopes cut by ravines bringing a typical view of badlands. In Lowland subregion the relief types are mainly of deltaic and alluvial-marine genesis. Here the contact depressions, alluvial river plains and alluvial marine plain are distinguished there. Contact depressions are the passive forms originated on contact place of submountain plains and combs of alluvial Kura plain. Near-bed zone along Kura river, and also the territory located between Kurovdag and Babazanan ridges and further to the east are of alluvial origin. The traces of "akhmazes", "cobs" and near-bed combs are typical for it. The recent delta of Kura river is characterized bylow near-bed combs and inter-comb swamped spaces. A great area of the South-Eastern Shirvan located to the east from Babazanan ridge is taken by specific forms of surface of the saline-eolian genesis. 1.2.2.5 Mugan-Salyan Region Mugan-Salyan region locates on the right bank of Kura river in the south-eastern part of the accumulative plain and consists of more lifted Mugan steppe and relatively lowered Salyan steppe. These steppes are separated by Akusha river, the channel of Kura river. Salyan steppe locates eastward from Mugan steppe and directly adjoins to Kura river bed. Deep saline depressions are typical for Mugan steppe south-eastern part. The origin of relief and ground of the present is because of accumulative activity of Kura and Araz rivers. Depending upon the deposits' spread and relief character Mugan and Salyan steppes are divided into alluvial plain covering the central, eastern and southern parts, and the submountain alluvial-proluvial and deluvial-proluvial plainon the west and south-west. There is a deltaic-marine plain on the south-east. Mugan alluvial plain is restricted from alluvial-proluvial and deluvial-proluvial inclined plain of the South and Lenkaran Mugan by marine terrace ledge passing on marks of 5-0.5 m. The onshore part is lowered and swamped due to a little inclination. Here, three sections - Kura river delta, Kyur Dili and Gizilagach gulf - are distinguished there. Subregion of Kura river delta is completely accumulative and formed by yearly hard flow of Kura river. Subregion of Kyur Dili is completely corresponded to the area of spit of the same name which has an island origin. The subregion had been formed due to washing of Kura river old delta and material transportation southward. Gizilagach subregion takes a coastal line of Gizilagach gulf. Due to formation of Kyur Dili spit formation the gulf had separated off sea and gained its recent outlines. The modern coastal line develops only under the actions of remove-bringing-up processes. Gulf bottom has a gentle profile, this promotes to its rapid drying out. 1.2.2.6 Lenkaran Region Lenkaran region is expressed by two subregions: the eastern part is taken Lenkaran lowland, and the western one - by Talysh Mountains. Talysh Mountains are characterized by relief the formation of main features of which it is caused by endogenic factors of morphogenesis. It is shown by coincidence of the morphostructures main elements strike with the geological structures orientation and relief structure details. According to plan the main mountain ridges if Talysh strike in the north-western (general Caucasian) direction well concordant with the tectonic structures orientation and represented by Talysh, Peshtasar, Burovar longitudinal ridges separated by Yardymly, Gosmalyan, Diman intermountain depressions. Here the prevalence of structural-denudation and volcanic-tectonic depression, but numerous erosion depressions are also met. Gravitational (collapses, landslides, falls) and fluvial processes have a wide spread here. In the middle mountain and low mountain belts the main morphostructures are river valleys, ravines and gullies. Lenkaran lowland represents a weakly inclined plain stretching from Astara town (state border with Iran) up to Mugan steppe. On the south the plain width doesn't exceed 5-7 km and increases on the north-eastern edge of the ridge up to 20-22 km in Masalli and Jalilabad regions. Except a narrow line directly adjoining to the Talysh ridge foothills, this plain has negative (in relation to ocean) hypsometric marks everywhere. On the north the transition from foothills to the low line is gentle, on the east this border is sharper characterized by outlines and terracing winding enough. A narrow shore line from Port-Ilich st. to Astara town is under a direct influence of the recent wave processes of the sea. Here the main relief forms are shore banks and dunes having the most development on shore part between Lenkaran town and Port-Ilich st. Due to active wave processes and submersions of Lenkaran lowland eastern part the abrasive shores are developed to the south from Lenkaran town. Higher part of the lowland represents a pre-mountain alluvial-proluvial plain on which the cones of river deposits are superposited. Lower part of the lowland is a young marine plain with old lagoons nearly dried out. Three series of marine terraces are observed on Lenkaran lowland surface: lower - accumulative, middle - abrasive-accumulative and higher - abrasive. Seaside accumulative plain (from -27 to 50 m) stretching from Goytepe river to Astarachai river is corresponded to the lower terraces and restricted on the west by distinctly expressed ledge - slope of zero terrace. The lain is characterized by surface little inclination, swamped lands and swamps, ravine cuts. Its surface has a little inclination to the north-east, its separation by the ravine-gully net and river valleys with terraced slopes increases in the same direction. Levels developed along on the foothills of Alashar-Burovar ridge on absolute heights 50, 80 and 100-130 m are corresponded to the group of middle abrasive-accumulative and abrasive terraces. Levels developed on absolute marks 150-170 m and 200-280 m are corresponded to the group of high abrasive terraces. They represent abrasive surface on tops and slopes of foothills heights and are the main relief forms of the hill-ridge foothills characterizing by specific separation. Proceeding from the morphological features of shore deposits, their position relatively the transition of incoming material, three types of shores had been distinguished on the investigated shore: accumulative, abrasive and stable (in dynamic-balance state). Accumulative shores take the regions of Port-Ilich - Olhovka and Lenkaranchai river delta and typical for shore parts on way of which there is a great longitudinal sediment flow. Such shores have a little inclination towards the sea. As a result the shore spits, underwater and shore banks and wide beaches are formed here. Abrasive shores developed in regions of villages of Vel, Shakhagach, Kaladagna are characterized by steep slopes and composed of loose deposits and clays. In these regions the force wave is directed for destruction of underwater and shortened parts of shore slope, transportation of loosed rocks towards the sea and their deposition in the lower part of the underwater slope. Stable shores developed in region of Olhovka, N.Nuvadi, Kamishevka villages, Astara town are characterized by balance of material quantity washed off the shore and deposits transported from land. 1.2.3. UNDERWATER SLOPE RELIEF CHARACTERISTICS According to the common accepted scheme the national sector of the Caspian Sea is divided into three large parts: Middle Caspian, Apsheron rapids and the South Caspian. Morphostructurally the relief of the Middle Caspian bottom is divided into three elements of the first order: shelf, continental slope and deep-water depression with maximal depth of 780 m. The southern part of the Middle Caspian restricted by Apsheron rapidson the south is corresponded to the sea national sector. Shelf plain is weakly inclined to the east, the continental slope is steep, and the depression has an asymmetric structure with maximal depths near azerbaijanian shores. To the south from Middle Caspian or Derbent depression there is narrow shallow stripe known as Apsheron rapids or Apsheron swell. Apsheron rapids separating Middle Caspian from the South one stretches from Apsheron peninsula to Krasnovodsk and Cheleken peninsulas of the eastern shore. On the west the trough width is about 60 km; the most depth (200 m) over the trough locates eastward Neft Dashlary, closer to the western sea shore. The geomorphological view of the South Caspian is more complex that the Middle Caspian. The shelf plain is complicated by some islands and banks basically related with mud volcanoes. The continental slope has a complex morphology and divided by a system of uplifts and troughs of the submeridional strike. The South Caspian depression has a maximal depth of 1025 m and the flattened relief. Generally, the gradual simplification of relief from west to the south and increase of accumulative role in bottom relief formation is typical for the South Caspian. Below there is a description of relief of the underwater slope of land regions, mentioned in item 1.2.2. Relief of the underwater slope of Samur-Devechi region is exclusively characterized by accumulative forms. Shelf plain width increases from the north to the south from 11-15 km near Samur river mouth up to 60 km in Siazan town latitude. But the inclination angles increase in back direction from 3-5' on the north. The increase of depth of the shelf brow from 65 m on the south to 100 m on the north is also observed. Within this region the depth increase is even. Underwater banks with relative height 0,5-2 m are traced along the coastline. The continental slope is relatively steep (inclination angles vary from 4-60 on the north to 1-1030' on the south) and was forming under the conditions of intensive Quaternary accumulation on background of the tectonic submersion of the Middle Caspian bed. Within the continental slope the depths vary from 120 to 700 m, and width -from 19 km near Nabran village to 67 km near Khachmaz town. Underwater-landslide events are typical for this line. The depression zone is oriented in the submeridional direction and has 145-km length with width of 28 km (on 300 m isobath). This zone is corresponded to the South depression of the Middle Caspian depression. The depression has a little inclination to the north (5-18'). The depression axis is displaced relatively the axis of more northern Derbent depression for 55 km eastward and there is a well expressed ledge between them. Relief of the underwater slope of Pri-Caspian - Apsheron region is characterized by more complex structure on the great part of area, especially corresponded to Apsheron rapids (Apsheron archipelago). Numerous outcrops of root rocks, forming rocky banks, underwater ridges, stones and numerous islands appear within a wide shallow stripe of this region. The modern grounds are thin, varying from 0 to 2-3, rare to 20 m and have a variegated composition. On the region north near Amiya cape there are three small rocky islands having a common name as Gyrag Dashlar. Between Gyrag Dashlar and Gilyazi Dili a sea bottom is full of underwater ridges with relative heights from 2-3 to 10 m. To the south-east from Gilyazi Dili cape there is Yashma is. formed by root rocks outcrops, somewhere crossed by shells. Apsheron peninsula water area is directly corresponded to Apsheron rapids area; the latter is a geomorphological reflection of Apsheron - Pri-Balkhan zone of tectonic uplifts. The western azerbaijanian part of troughs comes into the sea up to 150 m depth like a structural nose. The northern slope is gentle (inclination is 6-8'), slightly hilled somewhere. The southern flank is broken down enough having an inclination of 1-30. There is a depression 6 x 15 km size with maximal depth 455 m. Beyond the isobath 150 m there is a trough's central part having in cross-section a form of asymmetric bank with width of 10-15 km and length 50-60 km. To the north and east from Apsheron peninsula the water area is full of islands, banks separate above-water stones and underwater ridges known as Apsheron archipelago. The biggest islands of Apsheron archipelago - Pirallakhi is. and Chilov is. - are above water to the east from Apsheron peninsula. Eastward Chilov is. there is a stony bank with small islands - Neft Dashlary - above water. To the south from Apsheron peninsula there can be observed the following islands: Beyuk Zirya, Tava, Gum. Besides there are smaller islands and also some underwater stony ridges there. Thus, the investigated region is characterized by sharply crossed underwater relief. The relative fluctuations of heights reach 30-35 m with islands; but generally it is some meters of high. Relief of the underwater slope of Gobustan region is differ in the northern and southern parts, it allow distinguishing two subregions here: Pri-Apsheron and Baku archipelago. Pri-Apsheron subregion strikes up to latitude of Sangachal cape. In shelf part its gradual differ with flatness and gradual inclination (average inclination is 8-10') of surface off the shore towards the open sea. Shelf brow is on 65-100 m depth. Shelf plain has a maximal width of 55-60 km and complicated by separate islands and banks of the mud volcanic genesis. Apsheron archipelago subregion is characterized by sharp separation of shelf and frequent outcrops of root rocks forming numerous underwater ridges and stones. Shelf width decrease from the north to the south from 60 km in the latitude on Sangachal cape up to 35 km in the latitude of Bandovan cape. Shelf brow is on 70-100 depth on the north and 100-150 m on the south. The specific feature of the subregion is a great number of islands and banks. Generally, the elements of bottom relief structure have a regular south-eastern orientation and represented by three underwater banks alternating with relatively flattened bottom parts. The continental slope has a width from 18 to 27 km and average inclination 1045' (6040' maximal). Slope profile is concave or close to such. Some uplifts on top of which the mud volcanoes often located are confined to the slope. Between these ridges there are gulf-like lowers of relief opened into the deep-water depression of the South Caspian. Relief of the underwater slope of the Central Aran is characterized by accumulative forms. There is an absence of root rocks outcrops, and abrasive-sculptural forms of relief as well. Shelf plain is characterized by relative even relief with widened shallow stripe due to shallow Gizilagach gulf. Shelf brow is on 100-150 m depth, its width increases from 20-25 km on the north (near Kura river mouth) to 40-45 km in the latitude of Gizilagach gulf throat. The average angle of shelf inclination is 6' varying within 2-13'. At the same time the coastal shallow developed till 40-50 m has a very gentle inclination 2-5' with great width (20-30 km). The outward part of shelf is stepper - 10-12'. The specific feature of shelf zone is the presence of large delta and avandelta of Kura river. In this connection a coastal line projects far to the south-east. Another feature is the presence of separate mud volcanic cones forming banks of significant depths, and also Kyur Dashy, the only island in this region. The continental slope is characterized by complex morphologically. Two anticlinal ridges of the submeridional strike and separated by 800-m depression stretches parallely and southward from the anticlinal ridge. The latter stretches from Bandovan cape through Borisov bank and further south-south-east. These underwater banks are complicated by mud volcanoes cones. Relief of the underwater slope of Lenkaran region in shelf line is also characterized by accumulative flattened forms of relief. Shelf width decreases from the north to the south from 45 km to 20 km in the latitude of Astara town. Shelf brow locates on 100-150 m depth. Beyond the coastal shallow the shelf inclination angle increases gradually to 11-13'. The continental slope is complicated by some alternating uplifts and depressions of the meridional and strike having little amplitude and sizes. Their considerable part is associated with mud volcanic events. Reference
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