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plasters kungurian a circle. Plasters are lifted on a day surface owing to hydrochloric tectonics and make the top part Hydrochloric dome a file in which modern karstic processes intensively proceed. B 2.3. Bolshoe Bogdo mountain The height above the sea level is 149,6m. It is the highest point of Pricaspian lowland. Flank processes are observed on the most raised sections, especially in the area of Bolshoye Bogdo. Under the action of temporarily arising trickles, gravitational forces, wind the drift of superficial rocks and formation of delluvial aprons with the capacity up to 10-15m occurs. Thus, on hollows of a drain and gullies the drift of rocks with denudation plains onto accumulative ones and directly into the lake Baskunchack occurs. As a result of Khvalynian sediments more ancient rocks frequently submitted by gypsums drift onto the surface of the mountain. The lake Baskunchack B 2.4. Forms of rocks eolation on rocky sedimentations in near vicinities of Bolshoye Bogdo and « Singing rocks» In conditions of arid climate physical eolation and eolian processes are actively shown that results the formation of outliers of destruction, cellular forms. In separate places dense rocks collapse even up to sandy sediments. Wind makes deflation, corrosion, it sorts sand, carries out finer particles far beyond their initial distribution. B 2.5. The lake Baskunchack Baskunchack is the salty lake having the area about 115 km ². It is situated in the area of Ahtubinsk (Astrakhan region), geographical coordinates: 48°10’ northern latitude, 46°53’ eastern longitude/48,166667° northern latitude, 46,883333° eastern longitude, approximately in 270km to the north from the Caspian sea, and in 53 km to the east from Volga. Shore line in the lake is 21m below the sea level. Water in the lake is replenished with a help of the small river Gorkaya, area of a reservoir of which is 11000 km ², and with a help of 25 springs. Salinity of the lake is about 300 gram per litre. Capacity of salt superficial deposits in the lake is 10-18 m. As a result of salt 6 extraction craters with the depth up to 8 meters were formed. The depth of salt bedding is 6 km. In spring and in autumn the level of brine in the lake is maximal - up to 1 meter. In brine bacteria which bear salt live only. Since VIII century salt was extracted from the lake and sent along a Silky way. For the first time the lake Baskunchack is officially mentioned in 1627 in « The Book of Big Drawing », the first geographical description of Russia as a place, « where people extract salt pure as ice ». Today extremely pure salt of lake (99.8 % NaCl) forms up to 80 % from the general extraction of salt in Russia. Depending on need, from 1,5 up to 5 million tons of salt in a year are extracted here. For export of salt the Baskunchack railway was constructed. At the lake coast there are deposits of medical caolin. B 2.6. The hole Sharbulack The section is situated on the southern coast of the lake Baskunchack, to the east of mountain Bolshoye Bogdo. It is characterized by the presence of various forms of the karstic phenomena: caves, craters, gaps, gullies, cracks, etc. B 2.7. Karstic forms of relief The karst in the area of Baskunchack is caused by an output of sedimentary rocks позднепалеозойского age, submitted by bottom Permian gypsums of the Kungurianstage, onto the earth surface. Gypsums are lifted on a day time surface owing to hydrochloric tectonics; they represent the top part of the salt cupola massive in which present karstic processes intensively proceed.
Karstic gypsums border a bowl of the lake Baskunchack non-uniformly. I.V.Golovachyov offered the following allocation of karstic fields. Northern field surrounds a bowl of Baskunchack from the west, the north and the northeast. It is conditionally shared into three parts: western – from the gully Belaya (Ak - Dzhar) to the south and west in borders of Kungurian gypsums extension; northern (or central) field extends from the gully Belaya to the east up to the lake Karasun and to the north up to the lake Turgaj; the east field extends to the northeast coast of the lake Baskunchack between the river Gorkaya and the lake Karasun. The east field is bordered from the northern field by the river Gorkaya and also lasts to the east in borders of Kungurian gypsums extension. It consists of two detached closely spaced sections: Vac - Tausk and Tasbulack. The southern field is located on the southern coast of Baskunchack, to the east of Bolshoye Bogdo. Except for these three karstic fields the karstic removed and detached Cub- Тausk section is allocated. In the territory of the lake Baskunchack vicinities there are following forms of a karstic relief: 1. The negative superficial forms of the given area karstic relief are: corries, craters, hollows, gullies. 2. Gypsum hills with the height of up to 4,0 - 6,0m., extended from the northeast to the southwest on the northern and the northeast coast of the lake Baskunchack. 3. Grottoes, niches, shelters (Transitive forms from superficial karstic forms to underground ones). On the researched area, within the limits of the northern gypsum field there are three grottoes: "Lisiy", "Koljuchiy" and "Sharovskoy". 4. To underground karstic relief in the given area the following forms can be concerned: karst cracks, karstic wells and caves. 7 Karst cracks are the most typical for the natural boundary Sharbulack on the southern gypsum field, and also for the central part of the northern gypsum field. Tectonic cracks (formed owing to salt domn tectonics) are poorly treated by karstic processes. Mainly they are strongly attached to the raised sections raised and gypsum hills. The width of cracks, as a rule, is not great (up to 0,4 - 0,6m.). They have the depth up to 4,0 - 6,0m., and even more. So, the disconnected crack «Grelka", has the depth up to 12,5m. Bottoms of cracks are usually filled by detrital gypsums and friable alluvial sandy material. Karst wells. To karstic wells, the vertical cavities connected to the zone of vertical descending circulation of karstic waters concern. Depth of wells is up to 20,0m. Wells of the given area have a corrosion-erosive origin. They can be fragments of buried cavities, or the expanded channels of well - imaginative swallow holes. Wells are available in the central part of the northern gypsum field. Depth of them, as a rule, is not great - about 4,0 - 6,0m, width is about 1,0 - 2,0m, cross section is roundish. On subsurfaces channel corries can be met. B 2.8. Caves of corrosion – erosion type Cave Sharbulack. The entrance is situated in the natural hole Sharbulack, in the edge of karst-erosive hollow; it opens with a small descending window. The cave represents a twisting horizontal tailrace channel underrated in the distant part. The height of the entrance reaches 1,5m. The extension of the cave is about 40m. The maximal depth of the cave bedding from the steppe level is about 30m. In 2007 owing to entrance failure the cave became inaccessible for visiting. Cave Grobick. The entrance is situated in the natural hole Sharbulack in gypsum exposure. The cave represents a vertical crack with a horizontal bottom. Between vertical walls in 4,5m above the floor there is a large wedged gypsum block which teared off the arch and looks like a coffin. The maximum height of the entrance is 7,5m. Before the creation of the state reserve the cave had been actively visited by tourists. Cave Cherep. The entrance of the cave is situated in the natural hole Sharbulack, in a slope of karstic crater; it is submitted with a small entrance grotto with a height of 2,5m and width of 3m. In the depth of the grotto the block with the inscription and the image of a skull with bones is located. In the beginning of the last century the cave was named « Forty doors ».
Page 1 and 2: «Bogdinsko - Baskunchaksky» Geopa
Page 3 and 4: A. DEFINITION OF THE REGION BEING P
Page 5: B. SCIENTIFIC DESCRIPTION OF THE RE
Page 9 and 10: crack through which it is possible
Page 11 and 12: they are expressed by clay - siltst
Page 13 and 14: C. ARGUMENTS FOR NOMINATING THE TER
Page 15: 3. In the reserve sections on which

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