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1.
Currently, the species list of the macroalgae (excluding Charales) inhabiting the southern seas of Russia includes 388 species, specifically, 362 species in the Black Sea, 46 species in the Sea of Azov, and 70 species in the Caspian Sea. The species list has been increased by approximately 30% (96 species, most of them are registered in the Black Sea), compared to the data obtained 30 years ago. The green and red macroalgae of warm-water Mediterranean and tropical origin (Ceramium, Polysiphonia, Laurencia, Ulva, and Chaetomorpha) and brown algae (Sargassum and Cytoseira) were the key invaders. Nowadays the maximal species diversity is found on the Crimean coast and the Turkish coast of the Black Sea; and the species list of the Turkish coast differs significantly from all the other studied sites of the Black Sea. The number of the algae of the warm-water complex increased the most in 1990s–2000s in the Black Sea; species of boreal-tropical and subtropical origin dominate. However, such a tendency was not observed in the Sea of Azov and in the Caspian Sea, but expansion of the habitats of the brackish green algae has been registered.  相似文献   

2.
Doklady Earth Sciences - Based on the results of drifter observations in the western Black Sea, it is shown that winter intrusions of cold air (ICAs) are accompanied by wind of 10 m/s in speed and...  相似文献   

3.
Results of the complex analysis of the unique natural territory of Greater Sochi from the point of view of physical geography are considered. The region of Greater Sochi is located on the S slopes of the Main Caucasus chain on the eastern coast of the Black Sea. Morphometrical analysis of the relief and analysis air surface temperature and precipitation allowed to distinguish four specific subregions within the whole territory. It is demonstrated that the period of stable snow cover in the two subregions which occupy more than half of the region's area is sufficient for successful development of winter tourism. Peculiar combination of the mild climate of the coast with stable snow cover in the mountains till the beginning of summer provide strong attractivity of the region for all-the-year-round tourists inflow to the most modern recreational centre of Russia. The work provides the methodology for similar studies.  相似文献   

4.
We consider seismogravitational deformations on the Black Sea coast of the Caucasus. It is shown that in the segment from the settlement of Sukko to Cape Myskhako on the southern slope of the northwestern Caucasus underwent total seismotectonic reworking. The characteristic seismogravitational deformations are described. The boundaries and morphometric parameters of these deformations are defined, and typification of seismogenic structures is proposed. It is supposed that the high contemporary geodynamic activity in the region is related to underthrusting of the Shatskii swell beneath the folded-orogenic structures of the Caucasus.  相似文献   

5.
The study of the palaoseismic events in the karst terrains of the Bulgarian Black Sea coast is a very important up-to-date problem. The investigated region is one of the highest-energy regions in Bulgaria with established and recorded catastrophic historic and contemporary earthquakes. The terrain is subjected to the influence not only of its own earthquake foci but also of those in Romania and Russia. The palaeoearthquakes that caused considerable disturbances in the karst terrains along the Northern Bulgarian Black Sea coast have left significant traces. They caused disturbances in the environment and the relief (rearrangement of the surface and ground water karst basins, partially or entirely collapsed caves, deformed caves, oil, gas and salt intrusions and gravitationally formed caves). The ecological consequences in historic and contemporary aspects were catastrophic. The palaeoseismic dislocations were formed as a result of global, regional and local geodynamic events related with the destruction  相似文献   

6.
Different models are used to evaluate the seashore effects of the tsunami generated by an asteroid impacting the shallow-water plateau in the northwest basin of the Black Sea. The shortest distance between the impact location and the coast is about 185 km. The tsunami’s effects on the coastal regions depend on many factors among which the most important is asteroid size. The tsunami generated by a 250-m asteroid reaches the nearest dry land location in 35 min and needs about 2 h to arrive all over the Black Sea coast. The run-up value is about 2 m high on Turkish and Crimean coasts. In the western Black Sea regions, the wave height is about 3 m. The run-up values strongly depend on bathymetry and topography peculiarities. The run-up values in case of the tsunami generated by a 1,000-m-sized asteroid are up to five to six times larger than in case of the 250-m impactor, depending on location. Differences between the tsunami’s dynamics on coastal regions situated in the proximity of deep water and shallow water, respectively, are outlined. Aspects concerning accidental or deliberate nuclear explosions are briefly referred. Possible social consequences and prevention are shortly discussed.  相似文献   

7.
本文论述了气候自然变化及其异常、对盐湖、黑海沿岸、里海西岸和贝阿铁路的工程地质条件，带来的盐溶、斜坡作用活化，海侵和路基热融变形等工程地质灾害的现实性和严重性。指出今后进行铁路工程地质勘测设计时，必须考虑未来气候自然变化的重要意义。  相似文献   

8.
Doklady Earth Sciences - Signs of seawater intrusion into aquifers on the Black Sea coast have been considered. A review of publications showed that this dangerous hydrogeological process develops...  相似文献   

9.
The numerical results of thermal modeling studies indicate that the lithosphere is cold and strong beneath the Black Sea basin.The thermal lithospheric thickness increases southward from the eastern Pontides orogenic belt（49.4 km） to Black Sea basin（152.2 km）.The Moho temperature increases from 367℃in the trench to 978℃in the arc region.The heat flow values for the Moho surface change between 16.4 mW m-2 in the Black Sea basin and 56.9 mW m-2 in the eastern Pontides orogenic belt. Along the southern Black Sea coast,the trench region has a relatively low geothermal potential with respect to the arc and back-arc region.The numerical studies support the existence of southward subduction beneath the Pontides during the late Mesozoic-Cenozoic.  相似文献   

10.
Land-locked seas were polluted mainly by land-based pollutants. The Black Sea is the largest enclosed sea in the world and widely perceived to be heavily polluted. In order to determine the impact of marine activities on heavy metal pollution, shore (500 m distance from edge)–offshore (5,555 m distance from edge) samples of various stations through the Sinop, Samsun and Ordu cities located in the Middle Black Sea region between May 2000 and October 2001 were taken. In addition, samples were taken between April–May 2000 in order to designate the heavy metal pollution of certain rivers, streams, harbor and shores in Samsun’s boundary and 32 sampling stations for the routine pollution monitoring studies are selected including rivers, streams, industrial and domestic discharge points along the Black Sea coast of Turkey in the year 1996. Heavy metal concentrations of whole samples were measured and compared with “Quality Criteria of General Marine and Continental Inside Water Sources” currently effective in Turkey so as to bring up the levels of pollution in marine, rivers and streams.  相似文献   

11.
Extended along the Crimea–Caucasus coast of the Black Sea, the Crimean Seismic Zone (CSZ) is an evidence of active tectonic processes at the junction of the Scythian Plate and Black Sea Microplate. A relocation procedure applied to weak earthquakes (mb ≤ 3) recorded by ten local stations during 1970–2013 helped to determine more accurately the parameters of hypocenters in the CSZ. The Kerch–Taman, Sudak, Yuzhnoberezhnaya (South Coast), and Sevastopol subzones have also been recognized. Generalization of the focal mechanisms of 31 strong earthquakes during 1927–2013 has demonstrated the predominance of reverse and reverse–normal-faulting deformation regimes. This ongoing tectonic process occurs under the settings of compression and transpression. The earthquake foci with strike-slip component mechanisms concentrate in the west of the CSZ. Comparison of deformation modes in the western and eastern Crimean Mountains according to tectonophysical data has demonstrated that the western part is dominated by strike-slip and normal- faulting, while in the eastern part, reverse-fault and strike-slip deformation regimes prevail. Comparison of the seismicity and gravity field and modes of deformation suggests underthusting of the East Black Sea Microplate with thin suboceanic crust under the Scythian Plate. In the Yuzhnoberezhnaya Subzone, this process is complicated by the East Black Sea Microplate frontal part wedging into the marginal part of the Scythian Plate crust. The indentation mechanism explains the strong gravity anomaly in the Crimean Mountains and their uplift.  相似文献   

12.
We present the results of work on the compilation of a fuller and more comprehensive historical catalogue of earthquakes and tsunamis in the basin of the Black Sea and the Sea of Azov, an area of primary importance for the Russian Federation. In the 20th century, there were no significant tsunamis in the Black Sea; therefore, its coast was not considered tsunami-prone. A systematic search for new data sources, a revision of earlier ones, and the use of new approaches to the identification of tsunamigenic events resulted in a more than doubling of the number of known tsunamigenic events in this basin, bringing it up to 50. The total length of the new tsunami catalogue reached 3000 years, which makes it the second longest after the Mediterranean tsunami catalogue (about 4000 years). Taking into account the seismotectonic features of the Black Sea region, we processed data on historical tsunamis and analyzed the geographical and temporal distributions of their sources. For all tsunamigenic events we performed a parameterization of available information about their sources and coastal manifestations, evaluated the tsunami intensity based on the Soloviev-Imamura scale, and proposed a classification of tsunami and tsunami-like water wave disturbances based on their genesis. Tsunami run-up heights, inland penetration, and damage were estimated with regard for the newly found data. Among the identified historical events, there are devastating tsunamis with run-ups of 4-5 m, sometimes up to 6-8 m, which resulted in disastrous consequences for several ancient cities (Dioscuria, Sebastopolis, Bizone, and Panticapaeum) and many coastal settlements. Expert assessments of the most tsunami-prone areas of the coasts are given.  相似文献   

13.
This paper presents a rather complete picture of conditions of stagnation, recirculation and ventilation factors in the main industrialized and urban areas in Oman, developed along the coastal area. This study focuses on four sites; Sohar, Muscat, Sur, and Salalah. Each site has a local emission sources from transportation, industry and energy production activities. For the calculation of the integral quantities of the ability of the atmosphere dilution, hourly data of the wind velocity measured at a height of 10 m during 5 years (2000–2005) were used in the analysis. The results show that in the northern coast of Oman, along the bay of Sea of Oman, where 56% of the total population is concentrated and the main heavy industries of the country are amassed, the atmosphere is prone to stagnations in 74.4% of the time, while in the southern and east part of Oman, they occur only 23% and 51%, respectively. The bay of sea of Oman is high affected by land–sea breeze circulation that plays a substantial role in the simultaneous occurrence of recirculation equally to stagnation. This meso-scale effect is altered gradually during the passage of the synoptic-scale flow of the southeasterly summer monsoon that enhances the occurrence of the ventilation in Salalah (24.6% of time) and Sur (15.5%). In the northern coast of Oman, where the Hajir mountains suppressed the effect of the summer monsoon, a very weak tendency towards ventilation is observed (less than 6%). The southern summer monsoon over Oman is a source of life in this arid area and as well a source of clean air.  相似文献   

14.
Many geophysical characteristics of the Caspian and Black Seas' deep basins are similar, having: suboceanic type of the crust, low average seismic velocity, absence of earthquakes and relatively small variation of magnetic anomalies. However, the sediments in the Caspian Sea deep basin are folded whereas in the Black Sea they are approximately horizontal. The Caspian Sea also has a far greater thickness of sediment accumulation.

The deep basins of the Caspian, Black and Mediterranean seas represent a sequence having similar crustal structures but with a decreasing thickness of sediments and consolidated layer, in that order. It is possible that the intensive sinking and accumulation of sediments began earliest in the Caspian Sea and spreaded continuously to the Black Sea and then the Mediterranean Sea. The Caspian and Black Sea deep basins have existed for long time (perhaps from Paleozoic time or even earlier) as areas with a specific and related type of evolution.  相似文献   


15.
Deposits in southwestern Crimea that contain Late Albian, Middle Senomanian, and Middle Campanian volcanic material are described and dated. Supposedly volcanic edifices are identified in the Black Sea (the Shatsky Swell) based on seismic data. The Albian, Senomanian, and Campanian volcanic belts are reconstructed for the entire Black Sea Region. The suggestion is made that the Black Sea Basin formed as a back-arc basin that started from rifting in the Albian and finished with spreading of the oceanic crust in the Senomanian-Early Santonian.  相似文献   

16.
Sochi, the largest health resort in the country, is taken as an example to analyze a negative anthropogenic impact on the Black Sea coast environment, in particular on surface and sea waters. The paper gives the results of an integrated pollution study in Sochi, based on stationary systematic observations in the city of Sochi and Caucasus Biosphere Reserve, as well as on an integrated field survey of the resort's environment.  相似文献   

17.
Based on the conception of the cyclic (wave) nature of the changes in the circulation of the atmosphere of the Atlantic-European sector (index of the North Atlantic oscillations) and surface temperature of the Black Sea on scales smaller or equal to the century scale, anomalies of the winter surface temperature are analyzed. It is shown that in the phase of the maximum of the presumably 60-year cycle of changes in the NAO index a negative anomaly of surface temperature forms and in the phase of minimum of this scale of changes of NAO, there is a positive anomaly. Estimates of the possible thermal state of the surface of the Black Sea during the phase of the expected minimum in 2011–2020 of the 60-year cycle (60-year wave) of the NAO index are made. The possibility of a phase shift between changes in solar activity, the NAO index, and anomalies of temperature of the Black Sea on the scales of cyclic (wave) processes larger than 100 years is considered.  相似文献   

18.
Evolution of N.M. Strakhov’s views on the formation of diagenetic sulfides in Holocene-Quaternary rocks of the Black Sea is considered. It is shown that Strakhov actually discarded the statement of A.D. Arkhangel’skii about the migration of hydrotroilite from the Drevnechernomorsk (i.e., ancient Black Sea sediments) to the Neoeuxinian sequence and attribute the generation of sulfides in the hydrotroilite bed to the redox hydrosulfuric barrier. New data on sulfide distribution in Black Sea sediments and concept of ancient Black Sea sediments as semipermeable membranes suggest the decisive role of hydrosulfuric solutions in the generation of sulfide accumulations.  相似文献   

19.
Past hydrological interactions between the Mediterranean Sea and Black Sea are poorly resolved due to complications in establishing a high‐resolution time frame for the Black Sea. We present a new greigite‐based magnetostratigraphic age model for the Mio‐Pliocene deposits of DSDP Hole 380/380A, drilled in the southwestern Black Sea. This age model is complemented by 40Ar/39Ar dating of a volcanic ash layer, allowing a direct correlation of Black Sea deposits to the Messinian salinity crisis (MSC) interval of the Mediterranean Sea. Proxy records divide these DSDP deposits into four intervals: (i) Pre‐MSC marine conditions (6.1–6.0 Ma); (ii) highstand, fresh to brackish water conditions (~6.0–5.6 Ma); (iii) lowstand, fresh‐water environment (5.6–5.4 Ma) and (iv) highstand, fresh‐water conditions (5.4–post 5.0 Ma). Our results indicate the Black Sea was a major fresh‐water source during gypsum precipitation in the Mediterranean Sea. The introduction of Lago Mare fauna during the final stage of the MSC coincides with a sea‐level rise in the Black Sea. Across the Mio‐Pliocene boundary, sea‐level and salinity in the Black Sea did not change significantly.  相似文献   

20.
This paper presents the results of the recent paleoseismological studies covering the entire Kerch Peninsula. The Yuzhnoberezhnaya fold-and-thrust belt extending along the southern coast of Crimea in the Black Sea was earlier considered the principal seismogenic structure. Our findings suggest that the seismic hazard on the Kerch Peninsula is largely related to potential strong onshore earthquake sources. The observed discrepancy between instrumental and paleoseismological data suggests that seismic quiescence exists in this region at present.  相似文献   

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