Which river flows into the Caspian Sea. Why can the Caspian Sea be called neither a sea nor a lake? The Caspian Sea is a unique body of water

In dry and hot climates, a large amount sea ​​water evaporates, water molecules move into the air. Thus, every year such a huge amount of water particles is carried away from the surface of the Caspian Sea that all together they would fill a bowl with a volume of several hundred cubic kilometers. This amount of water could fill ten such reservoirs as Kuibyshevskoye.

But can water from the surface of the sea get into the bottom layers of the Caspian Sea, to a depth of 900-980 meters?

This is possible provided that the density of the surface layers of water is greater than the density of the bottom layers.

It is known that the density of sea water depends on salinity and temperature. The more salts the water contains, the denser it is, and therefore heavier. High temperature water is less dense than cold water. Only when low temperatures(about 0-4° heat) the opposite ratio is given when water, heating up, becomes more dense.

High salinity of the surface layers of the sea is created in the hot season, when the water evaporates strongly, but the salt remains in the sea. At this time, the salinity of surface waters turns out to be no less, and even slightly greater than the salinity of deep and near-bottom layers.

The temperature of surface waters in the warm season is the same everywhere, about 25-28°, that is, five times higher than at a depth of 150-200 meters. With the onset of the cold season, the temperature of the surface layers decreases and during a certain period it turns out to be 5-6° above zero.

The temperature of the bottom and deep (deeper than 150-200 m) layers of the Caspian Sea is the same (5-6°), practically unchanged throughout the year.

Under these conditions, it is possible for denser surface cold and highly saline water to sink into the bottom layers.

Only in the southern regions of the Caspian Sea, the surface water temperature, as a rule, does not drop to 5-6° even in winter. And, although the sinking of surface water into the depths directly in these areas cannot occur, water that has sank from the surface in the more northern parts of the sea is brought here by deep currents.

A similar phenomenon is observed in the eastern part of the border zone between the Middle and Southern Caspian Seas, where cooled surface waters descend along the southern slope of the border underwater threshold and then follow a deep current into the southern regions of the sea.

This widespread mixing of surface and deep waters is confirmed by the fact that oxygen was found at all depths of the Caspian Sea.

Oxygen can reach depths only with the surface layers of water, where it comes directly from the atmosphere or as a result of photosynthesis.

If there were no continuous supply of oxygen to the bottom layers, it would quickly be absorbed by animal organisms there or spent on the oxidation of soil organic matter. Instead of oxygen, the bottom layers would be saturated with hydrogen sulfide, which is what is observed in the Black Sea. The vertical circulation in it is so weak that oxygen in sufficient quantities does not reach the depth, where hydrogen sulfide is formed.

Although oxygen has been found at all depths of the Caspian Sea, it is not in the same quantity in different seasons of the year.

The water column is richest in oxygen in winter. The harsher the winter, that is, the lower the surface temperature, the more intense the aeration process occurs, which reaches the deepest parts of the sea. Conversely, several warm winters in a row can cause the appearance of hydrogen sulfide in the bottom layers and even the complete disappearance of oxygen. But such phenomena are temporary and disappear during the first more or less severe winter.

The upper water column to a depth of 100-150 meters is especially rich in dissolved oxygen. Here the oxygen content ranges from 5 to 10 cubic meters. cm in liter. At depths of 150-450 m, there is much less oxygen - from 5 to 2 cubic meters. cm in liter.

Below 450 m there is very little oxygen and life is represented very sparsely - several species of worms and mollusks, small crustaceans.

Mixing of water masses is also caused by surge phenomena and waves.

Waves, currents, winter vertical circulation, surges, and surges act constantly and are important factors in water mixing. It is not surprising, therefore, that no matter where we take a water sample in the Caspian Sea, its chemical composition will be constant everywhere. If there were no mixing of waters, all living organisms at great depths would die out. Life would only be possible in the photosynthetic zone.

Where the waters mix well and this process occurs quickly, for example in shallow areas of the seas and oceans, life is richer.

The constancy of the salt composition of the water of the Caspian Sea is a general property of the waters of the World Ocean. But this does not mean that the chemical composition of the Caspian Sea is the same as in the ocean or in any sea connected to the ocean. Consider a table showing the salt content in the waters of the ocean, the Caspian Sea and the Volga.

The table shows that ocean water has very little in common with river water in terms of salt composition. In terms of salt composition, the Caspian Sea occupies an intermediate position between the river and the ocean, which is explained by the great influence of river flow on the chemical composition of Caspian water. The ratio of salts dissolved in water Aral Sea, is closer to the salt composition of river water. This is understandable, since the ratio of the volume of river flow to the volume of water in the Aral Sea is much greater than for the Caspian Sea. Large quantity sulphate salts in the Caspian Sea gives its water a bitter-salty taste, distinguishing it from the waters of the oceans and seas connected to them

The salinity of the Caspian Sea continuously increases towards the south. In the pre-estuary space of the Volga, a kilogram of water contains hundredths of a gram of salts. In the eastern regions of the Southern and Middle Caspian Sea, salinity reaches 13-14‰

Salt concentration in Caspian water small. So, in this water you can dissolve almost twenty times more salts than are present in it.

B.A. Shlyamin. Caspian Sea. 1954

Caspian Sea- the largest lake on Earth, located at the junction of Europe and Asia, called the sea because of its size. Caspian Sea is a closed lake, and the water in it is salty, from 0.05% near the mouth of the Volga to 11-13% in the southeast.
The water level is subject to fluctuations, currently approximately 28 m below the level of the World Ocean.
Square Caspian Sea currently - approximately 371,000 km2, maximum depth - 1025 m.

Length of coastline Caspian Sea is estimated at approximately 6,500 - 6,700 kilometers, with islands - up to 7,000 kilometers. Shores Caspian Sea Most of its territory is low-lying and smooth. In the northern part, the coastline is indented by water channels and islands of the Volga and Ural deltas, the banks are low and swampy, and the water surface in many places is covered with thickets. The east coast is dominated by limestone shores adjacent to semi-deserts and deserts. The most winding shores are on the western coast in the area of ​​the Absheron Peninsula and on the eastern coast in the area of ​​the Kazakh Gulf and Kara-Bogaz-Gol.

IN Caspian Sea 130 rivers flow in, of which 9 rivers have a delta-shaped mouth. Large rivers flowing into the Caspian Sea are the Volga, Terek (Russia), Ural, Emba (Kazakhstan), Kura (Azerbaijan), Samur (Russian border with Azerbaijan), Atrek (Turkmenistan) and others.

Map of the Caspian Sea

The Caspian Sea washes the shores of five coastal states:

Russia (Dagestan, Kalmykia and Astrakhan region) - in the west and northwest, coastline length 695 kilometers
Kazakhstan - in the north, northeast and east, the length of the coastline is 2320 kilometers
Turkmenistan - in the southeast, the length of the coastline is 1200 kilometers
Iran - in the south, coastline length - 724 kilometers
Azerbaijan - in the southwest, the length of the coastline is 955 kilometers

Water temperature

is subject to significant latitudinal changes, most clearly expressed in winter, when the temperature varies from 0 - 0.5 °C at the ice edge in the north of the sea to 10 - 11 °C in the south, that is, the difference in water temperature is about 10 °C. For shallow water areas with depths less than 25 m, the annual amplitude can reach 25 - 26 °C. On average, the water temperature off the west coast is 1 - 2 °C higher than that on the east, and in the open sea the water temperature is 2 - 4 °C higher than off the coast.

Climate of the Caspian Sea- continental in the northern part, temperate in the middle part and subtropical in the southern part. In winter, the average monthly temperature of the Caspian Sea varies from?8?10 in the northern part to +8 - +10 in the southern part, in summer - from +24 - +25 in the northern part to +26 - +27 in the southern part. The maximum temperature recorded on the east coast was 44 degrees.

Animal world

The fauna of the Caspian Sea is represented by 1809 species, of which 415 are vertebrates. IN Caspian Sea 101 species of fish are registered, and it contains the majority of the world's sturgeon reserves, as well as freshwater fish such as roach, carp, and pike perch. Caspian Sea- habitat for fish such as carp, mullet, sprat, kutum, bream, salmon, perch, pike. IN Caspian Sea also inhabited by a marine mammal - the Caspian seal.

Flora

Flora Caspian Sea and its coastline is represented by 728 species. From plants to Caspian Sea The predominant algae are blue-green, diatoms, red, brown, characeae and others, and flowering algae include zoster and ruppia. By origin, the flora belongs mainly to the Neogene age, however, some plants were brought in Caspian Sea by a person knowingly or on the bottoms of ships.

Oil and gas production

IN Caspian Sea Many oil and gas fields are being developed. Proven oil resources in Caspian Sea are about 10 billion tons, the total resources of oil and gas condensate are estimated at 18 - 20 billion tons.

Oil production in Caspian Sea began in 1820, when the first oil well was drilled on the Absheron shelf. In the second half of the 19th century, oil production began on an industrial scale on the Absheron Peninsula, and then in other territories.

In addition to oil and gas production, on the coast Caspian Sea Salt, limestone, stone, sand, and clay are also mined on the Caspian shelf.

Environmental issues

Environmental issues Caspian Sea associated with water pollution as a result of oil production and transportation on the continental shelf, the flow of pollutants from the Volga and other rivers flowing into Caspian Sea, the life activity of coastal cities, as well as the flooding of individual objects due to rising levels Caspian Sea. Predatory production of sturgeon and their caviar, rampant poaching lead to a decrease in the number of sturgeon and to forced restrictions on their production and export.

The Caspian Sea is the world's largest endorheic body of water, 28.5 m below the level of the World Ocean. The Caspian Sea stretches from north to south for almost 1200 km, the average width is 320 km, the length of the coastline is about 7 thousand km. As a result of a decrease in level, the area of ​​the Caspian Sea decreased from 422 thousand km2 (1929) to 371 thousand km2 (1957). The volume of water is about 76 thousand km3, the average depth is 180 m. The coefficient of coastal indentation is 3.36. The largest bays: Kizlyarsky, Komsomolets, Kara-Bogaz-Gol, Krasnovodsky, Mangyshlaksky.

There are about 50 islands with a total area of ​​350 km2. The most significant of them are: Kulaly, Tyuleniy, Chechen, Zhiloi. More than 130 rivers flow into the Caspian Sea. The Volga, Ural, Emba, Terek rivers (the total annual flow is 88% of the total river flow into the sea) flow into the northern part of the sea. On its western coast, the Sulak, Samur, Kura and other smaller rivers account for 7% of the total flow. The remaining 5% of the flow comes from the rivers of the Iranian coast.

Bottom relief of the Caspian Sea

Climate in the Caspian Sea

In the northern and middle parts of the Caspian Sea, from October to April, winds from the eastern quarter predominate, and from May to September, winds from the northwestern directions prevail. In the southern part of the Caspian Sea, the monsoon wind pattern is clearly pronounced.

The average long-term air temperature in the warm months (July-August) over the entire sea is 24-26° C. The absolute maximum (up to 44° C) is noted on the east coast. On average, 200 mm of precipitation falls over the sea per year, with 90-100 mm on the arid eastern coast and 1700 mm in the subtropical southwestern part of the coast. Evaporation in most of the water area is about 1000 mm/year, and in the eastern part of the South Caspian Sea and in the area of ​​the Absheron Peninsula up to 1400 mm/year.

Hydrological regime

The maximum wave height (11 m) is observed in the area of ​​the Absheron threshold. The water temperature of the surface layer of the sea in August is about 24-26 ° C in the Northern and Middle Caspian, up to 29 ° C in the South, 32 ° C in the Krasnovodsk Bay and over 35 ° C in the Kara-Bogaz-Gol Bay. In July–August, upwelling and associated temperature drops to 8–10° C are observed off the eastern coasts.

Ice formation in the northern part of the Caspian Sea begins in December, the ice remains for 2-3 months. In cold winters, drifting ice is carried south to the Absheron Peninsula.
Isolation from the World Ocean, the influx of river waters and the deposition of salts as a result of intense evaporation in the Kara-Bogaz-Gol Bay determine the unique salt composition of the water of the Caspian Sea - a reduced content of chlorides and an increased concentration of carbonates in comparison with the waters of the World Ocean. The Caspian Sea is a brackish water basin, the salinity of which is three times less than normal ocean water.

The average salinity of the waters in the northwestern part of the Caspian Sea is 1–2 ppm, in the area of ​​the northern border of the Middle Caspian Sea it is 12.7–12.8 ppm and in the Southern Caspian Sea it is 13 ppm; the maximum salinity (13.3 ppm) is observed on the eastern shores. In the Kara-Bogaz-Gol Bay, the salinity is 300 ppm. Seasonal changes in the salinity of the waters of the Middle and Southern Caspian Sea are 0.17 and 0.21 ppm, respectively. In the Northern and Southern Caspian Sea, due to a reduction in inflow and salinization during ice formation, salinity increases in winter. In the Southern Caspian at this time, salinity decreases due to decreased evaporation. In summer, an increase in river flow causes a decrease in the salinity of waters in the Northern and Middle Caspian, and increasing evaporation leads to an increase in the salinity of water in the Southern Caspian. Changes in salinity from surface to bottom are small. Therefore, seasonal fluctuations in temperature and salinity of water, causing an increase in density, determine the winter vertical circulation of water, which in the Northern Caspian extends to the bottom, and in the Middle Caspian - to a depth of 300 m. In the Southern Caspian, mixing of deep waters (up to 700 m) is associated with the overflow of cooling in winter, the waters of the Middle Caspian Sea through the Absheron threshold and the sliding of cooled waters of high salinity from the eastern shallow waters. Studies have shown that due to the increase in water salinity over the past 25 years, the depth of mixing has increased significantly, the oxygen content has accordingly increased, and hydrogen sulfide contamination of deep waters has disappeared.

Tidal fluctuations in the level of the Caspian Sea do not exceed 3 cm. Short-term non-periodic fluctuations caused by surge phenomena can cause an increase in the level to 2-2.2 m and a decrease to 2 m. Seiches are observed with a period from 10 minutes to 12 hours and an amplitude about 0.7 m. The range of seasonal level fluctuations is about 30 cm. A characteristic feature of the hydrological regime of the Caspian Sea is sharp interannual fluctuations in the average annual level. The average level from zero of the Baku water gauge for a century (1830-1930) was 326 cm. The highest level (363 cm) was observed in 1896. From 327 cm (1929) the level dropped to 109 cm (1954), i.e. by 218 cm. In the last decade, the level of the Caspian Sea has stabilized at low levels with interannual fluctuations of the order of ±20 cm. Fluctuations in the level of the Caspian Sea are associated with climate changes over the entire basin of this sea.

A system of measures is being developed to prevent a further drop in sea level. There is a project to transfer the waters of the northern rivers Vychegda and Pechora to the Volga River basin, which will increase the flow by approximately 32 km3. A project was developed (1972) to regulate the flow of Caspian waters into the Kara-Bogaz-Gol Bay.

, Kazakhstan, Turkmenistan, Iran, Azerbaijan

Geographical location

Caspian Sea - view from space.

The Caspian Sea is located at the junction of two parts of the Eurasian continent - Europe and Asia. The length of the Caspian Sea from north to south is approximately 1200 kilometers (36°34"-47°13" N), from west to east - from 195 to 435 kilometers, on average 310-320 kilometers (46°-56° c. d.).

The Caspian Sea is conventionally divided according to physical and geographical conditions into 3 parts - Northern Caspian, Middle Caspian and Southern Caspian. The conditional border between the Northern and Middle Caspian runs along the line of the island. Chechen - Cape Tyub-Karagansky, between the Middle and Southern Caspian Sea - along the line of the island. Residential - Cape Gan-Gulu. The area of ​​the Northern, Middle and Southern Caspian Sea is 25, 36, 39 percent, respectively.

Coast of the Caspian Sea

Coast of the Caspian Sea in Turkmenistan

The territory adjacent to the Caspian Sea is called the Caspian region.

Peninsulas of the Caspian Sea

• Ashur-Ada
• Garasu
• Zyanbil
• Khara-Zira
• Sengi-Mugan
• Chygyl

Bays of the Caspian Sea

• Russia (Dagestan, Kalmykia and Astrakhan region) - in the west and northwest, the length of the coastline is about 1930 kilometers
• Kazakhstan - in the north, northeast and east, the length of the coastline is about 2320 kilometers
• Turkmenistan - in the southeast, the length of the coastline is about 650 kilometers
• Iran - in the south, the length of the coastline is about 1000 kilometers
• Azerbaijan - in the southwest, the length of the coastline is about 800 kilometers

Cities on the Caspian Sea coast

On the Russian coast are the cities of Lagan, Makhachkala, Kaspiysk, Izberbash and the southernmost city of Russia, Derbent. Astrakhan is also considered a port city of the Caspian Sea, which, however, is not located on the shores of the Caspian Sea, but in the Volga delta, 60 kilometers from the northern coast of the Caspian Sea.

Physiography

Area, depth, volume of water

The area and volume of water in the Caspian Sea varies significantly depending on fluctuations in water levels. At a water level of −26.75 m, the area is approximately 371,000 square kilometers, the volume of water is 78,648 cubic kilometers, which is approximately 44% of the world's lake water reserves. The maximum depth of the Caspian Sea is in the South Caspian depression, 1025 meters from its surface level. In terms of maximum depth, the Caspian Sea is second only to Baikal (1620 m) and Tanganyika (1435 m). The average depth of the Caspian Sea, calculated from the bathygraphic curve, is 208 meters. At the same time, the northern part of the Caspian Sea is shallow, its maximum depth does not exceed 25 meters, and the average depth is 4 meters.

Water level fluctuations

Flora

The flora of the Caspian Sea and its coast is represented by 728 species. The predominant plants in the Caspian Sea are algae - blue-green, diatoms, red, brown, characeae and others, and flowering plants - zoster and ruppia. In origin, the flora is predominantly of Neogene age, but some plants were brought into the Caspian Sea by humans deliberately or on the bottoms of ships.

History of the Caspian Sea

Origin of the Caspian Sea

Anthropological and cultural history of the Caspian Sea

Finds in the Khuto Cave off the southern coast of the Caspian Sea indicate that man lived in these areas approximately 75 thousand years ago. The first mentions of the Caspian Sea and the tribes living on its coast are found in Herodotus. Around the V-II centuries. BC e. Saka tribes lived on the Caspian coast. Later, during the period of settlement of the Turks, in the period of the 4th-5th centuries. n. e. Talysh tribes (Talysh) lived here. According to ancient Armenian and Iranian manuscripts, Russians sailed the Caspian Sea from the 9th-10th centuries.

Research of the Caspian Sea

Research of the Caspian Sea was started by Peter the Great, when, on his order, an expedition was organized in 1714-1715 under the leadership of A. Bekovich-Cherkassky. In the 1720s, hydrographic research was continued by the expedition of Karl von Werden and F. I. Soimonov, and later by I. V. Tokmachev, M. I. Voinovich and other researchers. At the beginning of the 19th century, instrumental surveys of the shores were carried out by I. F. Kolodkin, in the mid-19th century. - instrumental geographical survey under the direction of N. A. Ivashintsev. Since 1866, for more than 50 years, expeditionary research on the hydrology and hydrobiology of the Caspian Sea was carried out under the leadership of N. M. Knipovich. In 1897, the Astrakhan Research Station was founded. In the first decades of Soviet power, geological research by I.M. Gubkin and other Soviet geologists was actively carried out in the Caspian Sea, mainly aimed at searching for oil, as well as research into the water balance and level fluctuations of the Caspian Sea.

Economy of the Caspian Sea

Oil and gas production

Many oil and gas fields are being developed in the Caspian Sea. Proven oil resources in the Caspian Sea are about 10 billion tons, total oil and gas condensate resources are estimated at 18-20 billion tons.

Oil production in the Caspian Sea began in 1820, when the first oil well was drilled on the Absheron shelf near Baku. In the second half of the 19th century, oil production began on an industrial scale on the Absheron Peninsula, and then in other territories.

Shipping

Shipping is developed in the Caspian Sea. There are ferry crossings on the Caspian Sea, in particular, Baku - Turkmenbashi, Baku - Aktau, Makhachkala - Aktau. The Caspian Sea has a shipping connection with the Sea of ​​Azov through the Volga, Don and Volga-Don Canal rivers.

Fishing and seafood production

Fishing (sturgeon, bream, carp, pike perch, sprat), caviar production, as well as seal fishing. More than 90 percent of the world's sturgeon catch occurs in the Caspian Sea. In addition to industrial mining, illegal fishing of sturgeon and their caviar flourishes in the Caspian Sea.

Recreational resources

The natural environment of the Caspian coast with sandy beaches, mineral waters and healing mud in the coastal zone creates good conditions for recreation and treatment. At the same time, in terms of the degree of development of resorts and the tourism industry, the Caspian coast is noticeably inferior to the Black Sea coast of the Caucasus. At the same time, in recent years, the tourism industry has been actively developing on the coasts of Azerbaijan, Iran, Turkmenistan and Russian Dagestan. In Azerbaijan, the resort area in the Baku region is actively developing. At the moment, a world-class resort has been created in Amburan, another modern tourist complex is being built in the area of ​​​​the village of Nardaran, and holidays in the sanatoriums of the villages of Bilgah and Zagulba are very popular. A resort area is also being developed in Nabran, in northern Azerbaijan. However, high prices, a generally low level of service and a lack of advertising lead to the fact that there are almost no foreign tourists at the Caspian resorts. The development of the tourism industry in Turkmenistan is hampered by a long-term policy of isolation, in Iran - Sharia laws, due to which mass holidays of foreign tourists on the Caspian coast of Iran are impossible.

Environmental issues

Environmental problems of the Caspian Sea are associated with water pollution as a result of oil production and transportation on the continental shelf, the flow of pollutants from the Volga and other rivers flowing into the Caspian Sea, the life activity of coastal cities, as well as the flooding of individual objects due to rising levels of the Caspian Sea. Predatory production of sturgeon and their caviar, rampant poaching lead to a decrease in the number of sturgeon and to forced restrictions on their production and export.

International status of the Caspian Sea

Legal status of the Caspian Sea

After the collapse of the USSR, the division of the Caspian Sea has long been and still remains the subject of unresolved disagreements related to the division of Caspian shelf resources - oil and gas, as well as biological resources. For a long time, negotiations were ongoing between the Caspian states on the status of the Caspian Sea - Azerbaijan, Kazakhstan and Turkmenistan insisted on dividing the Caspian along the median line, Iran insisted on dividing the Caspian by one-fifth between all Caspian states.

In relation to the Caspian Sea, the key is the physical-geographical circumstance that it is a closed inland body of water that does not have a natural connection with the World Ocean. Accordingly, the norms and concepts of international maritime law should not automatically apply to the Caspian Sea, in particular, the provisions of the 1982 UN Convention on the Law of the Sea. Based on this, in relation to the Caspian Sea it would be unlawful to apply such concepts as “territorial sea”, “exclusive economic zone", "continental shelf", etc.

The current legal regime of the Caspian Sea was established by the Soviet-Iranian treaties of 1921 and 1940. These treaties provide for freedom of navigation throughout the sea, freedom of fishing with the exception of ten-mile national fishing zones and a ban on vessels flying the flag of non-Caspian states sailing in its waters.

Negotiations on the legal status of the Caspian Sea are currently ongoing.

Delineation of sections of the Caspian seabed for subsoil use

The Russian Federation concluded an agreement with Kazakhstan on delimiting the bottom of the northern part of the Caspian Sea in order to exercise sovereign rights to subsoil use (dated July 6, 1998 and the Protocol thereto dated May 13, 2002), an agreement with Azerbaijan on delimiting adjacent areas of the bottom of the northern part of the Caspian Sea (dated September 23, 2002), as well as the trilateral Russian-Azerbaijani-Kazakh agreement on the junction point of the demarcation lines of adjacent sections of the bottom of the Caspian Sea (dated May 14, 2003), which established the geographical coordinates of the dividing lines limiting the sections of the bottom within which the parties exercise their sovereign rights in the field of exploration and production of mineral resources.

Not all of the countries located on the shores of the Caspian Sea can be listed.

Countries on the Caspian Sea

Caspian Sea is the largest inland body of water on our planet by area. It also has no churn. The Caspian Sea is classified in different ways: as the world's largest lake and as a full-fledged sea. Its surface area is 371,000 km 2 (143,200 mi 2) and its volume is 78,200 km 3. Maximum depth 1025 m. Sea salinity is about 1.2% (12 g/l). The water level in the sea constantly fluctuates due to tectonic movements and high air temperatures. Today it is 28 m below sea level.

Even the ancient inhabitants who inhabited the coast of the Caspian Sea perceived it as a real ocean. It seemed to them limitless and very large. The word “Caspian” comes from the language of these peoples.

What countries are located on the shores of the Caspian Sea?

Sea waters wash the shores of 5 coastal states. This:

• Russia. The coastal zone covers Kalmykia, Dagestan and the Astrakhan region in the northwest and west. The length of the coastline is 695 km.
• Kazakhstan. The coastal zone covers the east, north and northeast of the state. The length of the coastline is 2320 km.
• Turkmenistan. The coastal zone covers the southeast of the country. The length of the coastline is 1200 km.
• Iran. The coastal zone covers the southern part of the state. The length of the coastline is 724 km.
• Azerbaijan. The coastal zone covers the southwest of the country. The length of the coastline is 955 km.

In addition, this body of water is the main object of the International Society, since it has huge reserves of natural gas and oil. The Caspian Sea is only 700 miles long, but it contains six basins with hydrocarbon reserves. Most of them have not been mastered by humans.