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1.
S. F. Dotsenko 《Physical Oceanography》2005,15(6):363-369
We perform the numerical analysis of the propagation of tsunamis in the Black Sea from the zones of seismic generation located
to the south of the Crimea and in the northwest part of the sea. It is shown that the tsunamis induced by earthquakes in the
Crimean seismic zone are entrapped by the nearest part of the shelf and do not result in noticeable oscillations of level
in the northwest part of the sea. This enables us to explain the absence of manifestations of tsunamis in 1927, 1939, and
1966 near Odessa. The tsunami waves generated by earthquakes in the northwest part of the sea are characterized by the directivity
of their propagation. The wave height is maximum in the areas corresponding to the north and east directions of propagation.
Hence, the north coast of the sea and the Kalamit Bay (Crimean Peninsula) are characterized by elevated tsunami hazard for
earthquakes occurring in the northwest part of the Black Sea.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 46–53, November–December, 2005. 相似文献
2.
N. A. Diansky V. V. Fomin N. V. Zhokhova A. N. Korshenko 《Izvestiya Atmospheric and Oceanic Physics》2013,49(6):611-621
We suggested a method for modelling the transport of pollutants over the Black Sea water basin adjacent to Big Sochi. The model is based on the application of the Institute of Numerical Mathematics Ocean Model (INMOM) over the entire basin of Big Sochi in two versions: M1 and M2. In the first version, we use uniform spatial resolution of the model with a step of ～4 km; in the M2 version, the resolution is not uniform. The step decreases to 50 m in the basin of Big Sochi. The M2 version is used only in the periods when pollution transport is simulated, for which the initial hydrothermodynamic state is specified from the M1 version. Both versions reflect a complex character of Black Sea circulation; however, the M2 version more adequately reproduces the eddy circulation in its eastern part, where the horizontal resolution of the M2 version is higher. A conclusion is made on this basis that, in order to reproduce the eddy structure of the Black Sea circulation, the resolution of the model should be on the order of 1.5 km and the main factor of the formation of the quasi-stationary Batumi anticyclonic eddy is the topographic peculiarities in this part of the sea. The pollution spreading from the Sochi, Khosta, and Mzymta rivers and from 18 pipes of deep-water sewage was simulated for the flood periods from April 1, 2007, to April 30, 2007. It was shown that mesoscale eddy formations that form a complex three-dimensional structure of pollution spreading make the greatest contribution to the spread of pollution. 相似文献
3.
In the austral summer of 2007, 20.5 km of high-resolution over-sea-ice seismic reflection data were collected in the Granite
Harbor region of southern McMurdo Sound over the Mackay Sea Valley. The goal of the survey was to image thin pelagic sediment
deposited in the Mackay Sea Valley after the Last Glacial Maximum. A generator–injector air gun was lowered beneath the sea
ice through holes drilled by an auger drill system. The recording system was a 60 channel snow streamer with vertically oriented
gimbaled geophones spaced 25 m apart. Unique problems in the over-sea-ice seismic reflection survey—noise from the ice column
flexing and timing delays caused by trapped air at previous shot points—were overcome to improve the quality of the seismic
data. The Mackay Sea Valley survey produced seismic data with a vertical resolution of 6.3 m. The processed seismic data show
pelagic sediment thickness of up to 50 m within the Mackay Sea Valley with some locations showing possible older sediments
beneath the pelagic sediment layer. 相似文献
4.
Regional deep seismic sounding—refracted wave seismic profiles across the Sea of Azov, the Caspian, and the Black seas carried out by the Shirshov Institute of Oceanology, Russian Academy of Sciences, in 1957–2002 with the use ocean bottom seismographs—provided information on the deep structure of the regions studied. Multichannel seismic profiling helped to refine the structure of the sedimentary cover. A combined interpretation of the reflection and refraction data allowed us to construct structural-lithological models of the southern seas of Russia and to estimate their oil and gas potential. 相似文献
5.
This work is based upon results of interpretation of about 8872 km-long regional seismic lines acquired in 2011 within the international project Geology Without Limits in the Black Sea. The seismic lines cover nearly the entire Black Sea Basins, including Russia, Turkey, Ukraine, Romania and Bulgaria sectors. A new map of acoustic basement relief and a new tectonic structure scheme are constructed for the Black Sea Basins. The basement of the Black Sea includes areas with oceanic crust and areas with highly rifted continental crust. A chain of buried seamounts, which were interpreted as submarine volcanoes of Late Cretaceous (Santonian to Campanian) age, has been identified to the north of the Turkish coast. On the Shatsky Ridge, probable volcanoes of Albian age have also been recognized. Synorogenic turbidite sequences of Paleocene, Eocene and Oligocene ages have been mapped. In the Cenozoic, numerous compressional and transpressional structures were formed in different parts of the Black Sea Basin. During the Pleistocene–Quaternary, turbidites, mass-transport deposits and leveed channels were formed in the distal part of the Danube Delta. 相似文献
6.
Model of palaeoenvironmental evolution of the Black Sea region during the last glacial maximum—Holocene 总被引：1，自引：0，他引：1
I. Genov 《Oceanology》2009,49(4):540-557
A model for the palaeoenvironmental evolution of the Black Sea and its adjacent basins during the past 20.000 years, in which
variations in sedimentation, erosion, and hydrologic processes as a result of climatic change are taken into consideration,
is developed. The data used include those from five cruises in the Black Sea with the participation of the author, seismo-acoustic
data in the possession of the Institute of Oceanology in Varna, and data from the published literature. The most important
result is that the water level of the Black Sea is controlled largely by that of the Marmara Sea via the Bosporus sill. The
water circulation in the south part of the Bosporus channel as natural regulative mechanism of the Black Sea level during
11800–9000 yr C14 BP is produced. A succession of climatic and water conditions for the Black Sea by pollen analysis is presented. The linear
ridges on the Black Sea shelf as result of the lower Holocene regression are proved by means of a stratigraphic interpretation
of the seismo-acoustic profiles. The levels of the Black Sea, Marmara Sea, and Mediterranean at regarded intervals of time
are presented. An attempt at explanation of maximum number of facts from the study region with this model is made. 相似文献
7.
The water dynamics and hydrological structure in the active (oxygen-containing) layer are considered on the basis of the hydrological survey carried out in the 50-mile near-shore zone of the Russian sector of the Black Sea in August 2004 and over the permanent section from Gelendzhik to the central part of the sea. Five mesoscale eddy structures of different signs were observed in the Main Black Sea Current between Sochi and the Kerch Strait. Such a dynamic situation contributed to the intensive horizontal water exchange between the near-shore and open sea waters as well as to the redistribution of water masses over the vertical in the active sea layer, which is indicated by the deepening of the top boundary of the hydrogen sulfide zone in the Russian sector of the sea by 15–20 m. 相似文献
8.
A number of significant hydrologicla and chemical parameters of the Black Sea shelf area have been identified and investigated:
the inter-annual variability of the mean annual and seasonal (winter and summer) values of the air and seawater temperatures
and salinity in the vicinity of Odessa; silicon and phosphate concentrations averaged over the north-western Black Sea shelf
area (NWBS); discharges of the Danube and Dnieper rivers; mean surface and near-bottom oxygen concentrations in summer acquired
through the analysis of the summarized data collected at three oceanographic stations occupied between Bolshoi Fontan and
the Tendra isthmus from the early 1950s up to date. From these data, the variability of the areas subject to oxygen deficit
in the near-bottom layer of the NWBS shelf during the summers of 1973–1994 has been assessed. Predominant oscillation periods
and trends in the inter-annual variability of the studied parameters have been revealed and their relationship and climatic
dependence has been demonstrated.
Translated by Vladimir A. Puchkin. 相似文献
9.
Ingrid Marie Hasle Amundsen Maria Blinova Berit Oline Hjelstuen Rolf Mjelde Haflidi Haflidason 《Marine Geophysical Researches》2011,32(4):441-453
The northeastern high-latitude North Atlantic is characterised by the Bellsund and Isfjorden fans on the continental slope
off west Svalbard, the asymmetrical ultraslow Knipovich spreading ridge and a 1,000 m deep rift valley. Recently collected
multichannel seismic profiles and bathymetric records now provide a more complete picture of sedimentary processes and depositional
environments within this region. Both downslope and alongslope sedimentary processes are identified in the study area. Turbidity
currents and deposition of glacigenic debris flows are the dominating downslope processes, whereas mass failures, which are
a common process on glaciated margins, appear to have been less significant. The slide debrite observed on the Bellsund Fan
is most likely related to a 2.5–1.7 Ma old failure on the northwestern Barents Sea margin. The seismic records further reveal
that alongslope current processes played a major role in shaping the sediment packages in the study area. Within the Knipovich
rift valley and at the western rift flank accumulations as thick as 950–1,000 m are deposited. We note that oceanic basement
is locally exposed within the rift valley, and that seismostratigraphic relationships indicate that fault activity along the
eastern rift flank lasted until at least as recently as 1.5 Ma. A purely hemipelagic origin of the sediments in the rift valley
and on the western rift flank is unlikely. We suggest that these sediments, partly, have been sourced from the western Svalbard—northwestern
Barents Sea margin and into the Knipovich Ridge rift valley before continuous spreading and tectonic activity caused the sediments
to be transported out of the valley and westward. 相似文献
10.
We analyze the annual average values and the anomalies of some hydrometeorological characteristics averaged over the period
since January till March near the South Coast of Crimea and in the open part of the Black Sea. It is shown that the sea-surface
temperature, the surface temperature of air, and the atmospheric precipitation in the Black-Sea region are lower than the
climatic mean values for the extremely high values of the index of North-Atlantic Oscillation (NAO index) (NAO ≥ 1) and the
surface temperature gradient between the Sargasso and Black Seas (SBS index) (SBS ≥ 1). In the years with NAO ≤ − 1 and SBS
≤ − 1, the indicated characteristics exceed the climatic mean values. The entire process of changes in the sign of anomalies
of the hydrometeorological characteristics runs with a period close to 20 yr. 相似文献
11.
A numerical model of the Black Sea region (Northeastern Mediterranean) is presented in which it is regarded as a part of the mosaic plate ensemble consisting of the fixed East European platform; the active Arabian, Adriatic, and Pannonian plates; and passive East and West Black Sea and Mysian microplates, which are embedded in a plastically deformable regional orogenic matrix. The fields of displacements, stresses, and deformations in the region are calculated by means of the finite element method within the framework of a linear-viscous rheology approach to a system with nonhomogeneous viscosities. The velocity field obtained is in good agreement with published data of direct observations of plate displacements in the region. In the pressure field, areas of low pressure and decompression are established in the western part of Black Sea and in the south of the Mysian microplate. The poles of rotation of the East and West Black Sea microplates and of the Mysian microplate are computed. For the latter two microplates, significant rotational components are suggested. The East Black Sea microplate acts mostly as indenter, which transmits the collisional motion from the Arabian plate to the southern edge of the East European platform including the Crimea. According to the geodynamical model, the rates of the Cenozoic sedimentation in the Black Sea depression at the collision stage (Oligocene-Pliocene) result from the greater compression of the East Black Sea microplate as compared to the West Black Sea microplate, which, probably, experienced a kind of extension. 相似文献
12.
A. A. Sizov 《Physical Oceanography》1997,8(4):261-267
The paper discusses the conditions corresponding to the largest and smallest North Atlantic Oscillations (NAOs). It is shown
that in winter, when NAOs are at a minimum, the number of cyclones over the Black Sea increases. At the same time, cloudiness
in the Atlantic-European section becomes heavier, compared with the largest NAO. Heavy cloudiness over the Balkan and Karpaty
mountains, with NAO at a minimum, may imply the greater likelihood of Balkan cyclones’ penetration into the Black Sea region.
The mechanism responsible for the generation of maximum (minimum) cloudiness in the Atlantic-European section is discussed.
Translated by Vladimir A. Puchkin. 相似文献
13.
The catastrophic tsunami of December 26, 2004 in Southeast Asia revealed the necessity of creating tsunami early warning systems
in the regions of the World Ocean where these systems are still absent but the potential hazard of tsunami generation exists.
The Black Sea is one of these regions. We present the general characteristic of the tsunami hazard in the Black-Sea region
and describe the most probable zones of tsunami generation, the specific features of tsunami propagation, and the parameters
of tsunamis according to the data of observations and the results of numerical simulations. We also discuss the possibility
of tsunami early warning on the basis of the operative data provided by the network of hydrometeorological and seismological
observation stations existing in this region.
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 57–66, September–October, 2008. 相似文献
14.
We develop a semiempirical spectral model of penetrating irradiance taking into account the biooptical characteristics of
the Black Sea. The evaluation of the contributions of the principal optically active components to the total absorption of
light in the sea shows that, in the short-wave range (400–500 nm), light is mainly absorbed by the dissolved organic matter
(41–77%). The contribution of phytoplankton to the total absorption attains its maximum values (26–37%) in the abyssal part
of the sea in the period of spring blooming of diatoms. In the coastal waters, the absorption of light by suspended nonalgae
particles in summer is almost twice as intense (20–30%) as in the open sea (8–13%). The analysis of the sensitivity of our
model shows that the absorption of light by dissolved organic matter is more significant for the estimation of the photosynthetically
active radiation in the Black Sea than the concentration of pigments and backscattering of light by suspended particles. The
comparison of the results of model computations with the data of measurements of the underwater irradiance reveals high accuracy
of the proposed model. 相似文献
15.
We perform the numerical analysis of the process of propagation of long waves in the northwest part of the Black Sea and consider
ten possible zones of the seismic generation of tsunamis. The numerical analysis is performed on a grid with steps of 500 m.
It is shown that the location of the tsunami source significantly affects the distribution of the heights of waves along the
coast. As a rule, the most intense waves are formed in the closest part of the coast. The earthquakes in the South-Coast seismic
zone do not lead to the formation of tsunamis in the west part of the sea. Only strong earthquakes in the northwest part of
the sea can be responsible for noticeable oscillations of the Black-Sea level. The period of tsunamis near Odessa is close
to 1 h and depends on the magnitude of the earthquake. In the region of Sevastopol, this period is 2--3 times smaller. In
the major part of the coastal points, the extreme elevations and lowerings of the sea level do not exceed (in modulus) the
initial displacements of the sea surface at the source of tsunamis. An intensification of waves emitted from the zones of
generation located in the deeper part of the investigated region was observed for some parts of the Romanian coast and the
west coast of Crimea. As the magnitude of the earthquake increases, the intensification of waves near the coast becomes more
pronounced. 相似文献
16.
O. A. Yunev 《Oceanology》2011,51(4):616-625
Using the data of daily primary production, as well as intraannual and long-term changes in the concentration of chlorophyll
“a” and hydrochemical characteristics, the annual primary production of phytoplankton in the deep-water part of the Black
Sea is estimated for the three key periods in the contemporary evolution of the sea: preeutrophication, very intense eutrophication,
and the present-day period characterized by deeutrophication. It is shown that eutrophication in the second part of the 20th
Century led to an increase in the production level not only in the shelf of the Black Sea, but also its deep-water areas.
By the end of the 1980s and the early 1990s, the value of the annual primary production in this part of the sea increased
from 63 ± 18 g C m−2 yr−1 (in the 1960s) up to 135 ± 30 g C m−2 yr−1. On the contrary, after 1993, mainly because of reduced runoff of biogenic substances into the Black Sea from land based
sources, there was a decrease in the annual production of phytoplankton in the deep-water areas of the sea, which is currently
about 105 g C m−2 yr−1. 相似文献
17.
A numerical technique is presented for simulating the hydrophysical fields of the Black Sea on a variable-step grid with refinement in the area of IO RAS polygon. Model primitive equations are written in spherical coordinates with an arbitrary arrangement of poles. In order to increase the horizontal resolution of the coastal zone in the area of the IO RAS polygon in the northeastern part of the sea near Gelendzhik, one of the poles is placed at a land point (38.35° E, 44.75° N). The model horizontal resolution varies from 150 m in the area of the IO RAS polygon to 4.6 km in the southwestern part of the Black Sea. The numerical technique makes it possible to simulate a large-scale structure of Black Sea circulation as well as the meso- and submesoscale dynamics of the coastal zone. In order to compute the atmospheric forcing, the results of the regional climate model WRF with a resolution of about 10 km in space and 1 h in time are used. In order to demonstrate the technique, Black Sea hydrophysical fields for 2011–2012 and a passive tracer transport representing self-cleaning of Gelendzhik Bay in July 2012 are simulated. 相似文献
18.
19.
In May 2007, the Marine Hydrophysical Institute of the Ukrainian National Academy of Sciences carried out an oceanographic
expedition in the northwest sector of the Black Sea. This expedition originates a series of surveys scheduled for this region.
It was realized within the framework of national and international projects, such as Climate, Ecoshelf, Stable Ecosystem, SESAM, ECOOP, and Oceanography. We present the data on the works carried out in this expedition and perform a brief analysis of the process of subduction
of waters on the northwest shelf. It is shown that, despite the abnormally warm preceding autumn–winter period, the wellpronounced
subduction of waters formed in the process of autumn–winter cooling was still observed over the drop of depth along the isopycnic
surfaces σt = 14.0 and σt = 14.5–14.6 in May 2007. New data on the intensity of vertical turbulent exchange over the continental slope in the northwest
part of the Black Sea are obtained. 相似文献
20.
Estimates of vertical turbulent diffusion coefficient (K t ) in the Black Sea pycnohalocline have been obtained from data of simultaneous observations of seawater temperature, salinity, density, and horizontal current velocity, obtained in the northeastern part of the Black Sea during 2013–2014 with a moored Aqualog profiler. A Munk and Andersson (1948) type parameterization, adapted for the Black Sea environment, is proposed for calculating K t . Strong short-period (several days) variability of turbulent exchange is revealed, induced by vertical shear variations of the current velocity. 相似文献