Rare and trace elements in modern bottom sediments of the Barents sea. Nd, Pb and Sr isotopic composition

2021 ◽  
pp. 444-472
Author(s):  
A.V. Maslov ◽  
◽  
N.V. Politova ◽  
N.V. Kozina ◽  
A.B. Kuznetzov ◽  
...  

The article presents a brief lithological description of the modern bottom sediments of the Barents Sea, selected in the 67th voyage of the R/V “Akademik Mstislav Keldysh” at the polygons: 1) “Pechora Sea”; 2) “Western slope of Kaninskoe shoal”; 3) “Central Barents Sea (Shtokman area)”; 4) “Russkaya Gavan’ fjord”; 5) “Medvezhinsky Trench”; 6) in the area to the south of Spitsbergen; 7) “Kola meridian”; 8) “Spitsbergen – Franz Josef Land archipelago”; 9) “Cambridge Strait”. The distribution of Cr, Ni, Cu, Zn, Cd, and Pb in samples of bottom sediments (pelitic, aleurite-pelitic and sandy-aleuritic-pelitic ooze) is compared with the background concentrations and contents of these elements in the Post-Archean Average Shale (PAAS). The data obtained are consistent with the notion that the distribution of heavy metals and other elements in the bottom sediments is controlled primarily by the global geochemical background. The relationship of the Sc, V, Cr, Ni, Y, Zr, Nb, Mo, Hf, Th, U and rare-earth elements concentrations with content of fine pelite (< 0.001 mm) fraction and organic carbon (Corg) is considered. It was found that most of these elements are characterized by a moderate positive correlation with the amount of fine pelite fraction in samples. By the magnitude of the correlation coefficient with the Corg content, all elements are attributed into three groups: (1) with moderate positive correlation, (2) weak positive correlation, (3) practically not pronounced correlation. The distribution in the bottom sediments of the Barents Sea of the element-indicators of the source rocks composition (Sc, Th, Co, Cr, La and Sm), as well as of rare earths, make it possible to consider that the majority of bottom sediments is mature in geochemical terms material, the sources of which were rocks of the Kola Peninsula and Spitsbergen (?). The bottom sediments of the Cambridge Strait are represented by geochemically less mature material, which, apparently, entered the sea as a result of erosion of the Franz Josef Land archipelago rocks. The established isotopic characteristics (εNd, 207Pb/206Pb and 87Sr/86Sr) of 17 samples of surface sediments suggest that the main contribution to the formation of bottom deposits of the central regions of the Barents Sea is made by rocks of the mainland part located in the influence zone of the North Cape Current. Archipelagos and islands (Franz Josef Land, Novaya Zemlya, etc.) that frame the Barents Sea supply a relatively small amount of clastic material that is carried by Arctic currents. The values of εNd and 87Sr/86Sr in the surface sediments of the central part of the Barents Sea and in the ice-rafted sediments carried by the Transpolar Drift showed a significant difference. This suggests that the contribution of such material to the formation of surface sediments of the Barents Sea is relatively small

2019 ◽  
Vol 485 (2) ◽  
pp. 207-211
Author(s):  
A. V. Maslov ◽  
N. V. Politova ◽  
V. P. Shevchenko ◽  
N. V. Kozina ◽  
A. N. Novigatsk ◽  
...  

The Co, Hf, Ce, Cr, Th, and REE systematics are analyzed for modern sediments collected by a bottom grab during the 67th and 68th cruises of R/V “Akademik Mstislav Keldysh” and samples taken in the Barents Sea bays and inlets. Our results indicate that most modern bottom sediments are composed of fine silicoclastic material enhanced with a suspended matter of the North Cape current, which erodes the western coast of Scandinavia, and due to bottom erosion of some marine areas, as well as erosion of rock complexes of the Kola Peninsula, Novaya Zemlya, and Franz Josef Land (local provenances). Material from Spitsbergen also probably played a certain role. In the southern part of the Barents Sea, clastic material is supplied by the Pechora River.


2021 ◽  
Vol 12 (3-2021) ◽  
pp. 88-97
Author(s):  
K.K. Moskvin ◽  

The paper describes species composition, distribution and biology of the polychaeta genus Pholoe in the north-east region of the Barents Sea (between Franz Josef Land and north-west coast of Novaya Zemlya archipelago). One species of the genu s was identified based on the reviewed morphological descriptions – Pholoe assimilis. The highest values of population density (1130 specimens/m2) and biomass (570 mg/m2) were registered in comparatively warm coastal waters of Novaya Zemlya archipelago. Pholoe assimilis’ population size structure based on the dorsal width of the fifth chaetiger was investigated for the first time. Size-frequency histograms indicate presence of at least four size classes.


2021 ◽  
pp. 899-943
Author(s):  
V.A. Shakhverdov ◽  
◽  
D.V. Ryabchuk ◽  
M.A. Spiridonov ◽  
V.A. Zhamoida ◽  
...  

A brief analysis of the history of environmental geological study of the Barents Sea is given. It shows that at the beginning of industrial development the geological environment was characterized by a low level of disturbance and pollution. On example of the Kola Bay, an assessment of the current environmental geological conditions of the fjords in the eastern part of the Barents Sea is given. Seismic-acoustic studies confirm the predominantly tectonic origin of the bay and the hazardous spread of gravitational rocks movement within the coastal slopes. The background geochemical characteristics of recent bottom sediments are quantified. It is shown that geochemical zoning of the bottom of the bay is a consequence of both natural and anthropogenic processes. According to the content of Cu, Zn, As, Cd, Pb, Hg and hexane-soluble petroleum products (PP) in the bottom sediments, the characteristics of various areas were obtained. It is shown that the distribution of PP and several other pollutants in the main components of aquatic and coastal geosystems is a leading element of the environmental monitoring system, quantitative assessment of anthropogenic impact and accumulated environmental damage. Active economic activity within the southern leg of the Kola Bay, as well as the naval bases, significantly affects the distribution of chemical elements. The data concerning distribution of chemical elements forms in bottom sediments are given that suggest a high probability of secondary pollution of the bottom water when the physicochemical conditions of sedimentation processes change. A comparative analysis showed that bottom sediments of the Kola Bay are characterized by the highest concentration of chemical elements in the North-West Region of the Russian Federation.


2021 ◽  
pp. 398-415
Author(s):  
N.V. Politova ◽  
◽  
T.N. Alekseeva ◽  
N.V. Kozina ◽  
M.D. Kravchishina ◽  
...  

The paper presents data from grain size and mineralogical analyzes of surface bottom sediment samples obtained on several cruises of the R/V Akademik Mstislav Keldysh (2016–2018) from different parts of the Barents Sea. Pebble and gravel material is found in surface sediments in the form of impurities scattered throughout the sea. Such a chaotic distribution pattern is apparently associated with ice separation. Coarse material is most common in the Barents Sea off the coast of the Kola Peninsula, off the coast of Novaya Zemlya, Spitsbergen, where it accumulates due to coastal abrasion. In addition, a fraction >1 mm is widespread at depths where fine fractions are stirred and leached. The most common sediments in coastal shallow water are sands. Sands (0.1–1 mm) are widespread in the southern and southeastern regions of the sea, in the region of the Pechora polygon, the Kaninsky shallow water, the Kola Peninsula, and in the northwest, off the coast of Svalbard. With increasing depth, the sands are replaced by mixed sediments with a low admixture of pelite. Pelitic sediments are prevalent in the central part of the sea. Precipitation with a pelitic fraction (<0.01 mm) of more than 50% occupy about 70% of the Barents Sea. They are widespread in deep-sea hollows and trenches, as well as in the numerous fiords of the North Island of Novaya Zemlya and Franz Josef Land. Surface sediments have a predominantly terrigenous composition; only at the border with the Norwegian Sea the proportion of biogenic material increases. The mineral composition of sediments is dominated by quartz and feldspars, clay minerals are mainly represented by illite, smectite and kaolinite.


Polar Record ◽  
1987 ◽  
Vol 23 (146) ◽  
pp. 511-529 ◽  
Author(s):  
William Barr

ABSTRACTIn the summer of 1908 the Mission Océanographique Arctique Française sailed from Dunkirk aboard the ketch Jacques Cartier. Sponsored by the Société d'Océanographie du Golfe de Gascogne and led by Charles Bénard, its major aims were to study the fisheries potential of the Barents Sea, to explore Gusinaya Zemlya on the south island of Novaya Zemlya, to chart and sound the bays and straits of that area, to carry out geological investigations, and to make a traverse of Matochkin Shar, which bisects Novaya Zemlya. The expedition established itself at Belush'ya Guba, from where Bénard and his companions explored much of Gusinaya Zemlya and surveyed, sounded and charted the adjacent waters. An attempt at crossing the south island, made by the medical officer Candiotti, was unsuccessful. Later, accompanied by the Russian geologist Vladimir Aleksandrovich Rusanov, Candiotti sailed through Matochkin Shar and made the first crossing of the north island, from Neznayemyy Zaliv to Krestovaya Guba. The expedition ended on rather a sour note: Bénard abandoned his ship and crew at Arkhangel'sk, leaving the organizing committee with the problems of unravelling the mess and repatriating the crew.


2019 ◽  
Vol 59 (3) ◽  
pp. 466-468
Author(s):  
S. L. Nikiforov ◽  
R. A. Ananiev ◽  
N. V. Libina ◽  
N. N. Dmitrevskiy ◽  
L. I. Lobkovskii

The results of recent geological and geophysical expeditions indicate the activation of hazardous natural phenomena associated with ice gouging and represent geohazard for almost all activities, including operation of the Northern Sea Route. Within the Barents Sea and the western part of the Kara Sea, the modern ice gouging is mainly associated with icebergs which are formed as a result of the destruction of the glaciers of Novaya Zemlya, the Spitsbergen archipelago and Franz Josef Land, while on the eastern shelf it is caused by the destruction of seasonal or perennial ice fields. Fixed furrows can be divided into modern coastal gouges or deep water ploughmarks. All deep water gouges within the periglacial and glacial shelf are of paleogeographical origin, but with different mechanisms of action on the seabed. These furrows were formed by floating ice on the periglacial shelf. On the glacial shelf deep water ploughmarks were formed by large icebergs, which could carry out the gouging even on the continental slope and deep-sea ridges of the Arctic Ocean.


2019 ◽  
Vol 485 (1) ◽  
pp. 71-75
Author(s):  
A. V. Maslov ◽  
A. B. Kuznetsov ◽  
N. V. Politova ◽  
N. V. Kozina ◽  
A. N. Novigatsky ◽  
...  

The isotopic characteristics ((Nd, 207Pb/206Pb, and 87Sr/86Sr) of the modern bottom sediments sampled in the Barents Sea during the 67th voyage of the R/V “Akademik Mstislav Keldysh” are considered. It is shown that the major contribution to the formation of the sediments in the central Barents Sea is made by rocks of the North European continental margin, which are found in the zone of influence of the North Cape Current. The values of (Nd, and 87Sr/86Sr are lower in the bottom sediments of this part of the sea than the corresponding characteristics of sedimentary material incorporated into ices and carried by the Transpolar Drift Stream. This allows one to conclude that such material has not contributed much to the sedimentation in the Barents Sea.


Vestnik MGTU ◽  
2020 ◽  
Vol 23 (2) ◽  
pp. 122-130
Author(s):  
E. A. Gorbacheva

Bioassay is used to study bottom sediment ecotoxicity in the central and eastern parts of the Barents Sea. The effect of sediment elutriates on the growth of microalgae Phaedactylum tricornutum Bohlin and survival of brine shrimp Artemia salina L. larvae has been studied. As shown by scientific evidence, low and moderately toxic bottom sediments are present in the Eastern Basin, West Novaya Zemlya and South Novaya Zemlya troughs along with non-toxic bottom sediments, which may be indicative of accumulation of pollutants in these areas of the Barents Sea. Toxic bottom sediments have not been found in the sea areas adjacent to them. Reduced survival rate in sediment elutriates of low and moderate toxicity has been shown predominantly by A. salina larvae. Only one sediment elutriate from the South Novaya Zemlya trough has had a slight toxic effect on Ph. tricornutum. The amount of fine-grained fraction (> 0.063 mm) in bottom sediments classified as low and moderately toxic is 24.8-66.8 % and do not differ from its amount found in bottom sediments classified as non-toxic - 27.8-76.9 %. The findings obtained are consistent with published chemical analysis data according to which the Eastern Basin, West Novaya Zemlya and South Novaya Zemlya troughs are included in the Barents Sea areas having highest amounts of a number of pollutants in bottom sediments.


Fluids ◽  
2021 ◽  
Vol 6 (12) ◽  
pp. 456
Author(s):  
Inna A. Nemirovskaya ◽  
Anastasia V. Khramtsova

The results of the study of hydrocarbons (HCs): aliphatic (AHCs) and polycyclic aromatic hydrocarbons (PAHs) in bottom sediments (2019 and 2020, cruises 75 and 80 of the R/V Akademik Mstislav Keldysh) in the Norwegian-Barents Sea basin: Mohns Ridge, shelf Svalbard archipelago, Sturfiord, Medvezhinsky trench, central part of the Barents Sea, Novaya Zemlya shelf, Franz Victoria trough are presented. It has been established that the organo-geochemical background of the Holocene sediments was formed due to the flow of sedimentary material in the coastal regions of the Barents Sea on shipping routes. The anthropogenic input of HCs into bottom sediments leads to an increase in their content in the composition of Corg (in the sandy sediments of the Kaninsky Bank at an AHC concentration up to 64 μg/g, when its proportion in the composition of Corg reaches 11.7%). The endogenous influence on the of the Svalbard archipelago shelf in Sturfiord and in the Medvezhinsky Trench determines the specificity of local anomalies in the content and composition of HCs. This is reflected in the absence of a correlation between HCs and the grain size composition of sediments and Corg content, as well as a change in hydrocarbon molecular markers. At the same time, the sedimentary section is enriched in light alkanes and naphthalene’s that may be due to emission during point discharge of gas fluid from sedimentary rocks of the lower stratigraphic horizons and/or sipping migration.


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