scholarly journals METHANE IN GROUND ICE AND FROZEN SEDIMENTS IN THE COASTAL ZONE AND ON THE SHELF OF KARA SEA

2018 ◽  
Vol 58 (1) ◽  
pp. 65-77 ◽  
Author(s):  
I. D. Streletskaya ◽  
A. A. Vasiliev ◽  
G. E. Oblogov ◽  
P. B. Semenov ◽  
B. G. Vanshtein ◽  
...  
Keyword(s):  
Coastal Zone ◽  
Kara Sea ◽  
Ground Ice

scholarly journals The Ice-Rich Permafrost Sequences as a Paleoenvironmental Archive for the Kara Sea Region (Western Arctic)

2021 ◽  
Vol 9 ◽  
Author(s):  
I. D. Streletskaya ◽  
A. A. Pismeniuk ◽  
A. A. Vasiliev ◽  
E. A. Gusev ◽  
G. E. Oblogov ◽  
...  
Keyword(s):  
Late Pleistocene ◽  
Marine Sediments ◽  
Isotope Composition ◽  
Kara Sea ◽  
Coastal Sediments ◽  
Organic Carbon Content ◽  
Ground Ice ◽  
Geochemical Composition ◽  
The Holocene ◽  
Mis 3

The Kara Sea coast and part of the shelf are characterized by wide presence of the ice-rich permafrost sequences containing massive tabular ground ice (MTGI) and ice wedges (IW). The investigations of distribution, morphology and isotopic composition of MTGI and IW allows paleoenvironmental reconstructions for Late Pleistocene and Holocene period in the Kara Sea Region. This work summarizes result of long-term research of ice-rich permafrost at eight key sites located in the Yamal, Gydan, Taimyr Peninsulas, and Sibiryakov Island. We identified several types of ground ice in the coastal sediments and summarized data on their isotopic and geochemical composition, and methane content. We summarized the available data on particle size distribution, ice chemical composition, including organic carbon content, and age of the enclosing ice sediments. The results show that Quaternary sediments of the region accumulated during MIS 5 – MIS 1 and generally consisted of two main stratigraphic parts. Ice-rich polygenetic continental sediments with syngenetic and epigenetic IW represent the upper part of geological sections (10–15 m). The IW formed in two stages: in the Late Pleistocene (MIS 3 – MIS 2) and in the Holocene cold periods. Oxygen isotope composition of IW formed during MIS 3 – MIS 2 is on average 6‰ lower than that of the Holocene IW. The saline clay with rare sand layers of the lower part of geological sections, formed in marine and shallow shelf anaerobic conditions. MTGI present in the lower part of the sections. The MTGI formed under epigenetic freezing of marine sediments immediately after sea regression and syngenetic freezing of marine sediments in the tidal zone and in the conditions of shallow sea.

Estimation of the seasonal input of freshwater in the Kara sea surface layer using hydrochemical proxies

2021 ◽  
Author(s):  
Uliana Kazakova ◽  
Alexander Polukhin
Keyword(s):  
Surface Layer ◽  
Coastal Zone ◽  
Dissolved Inorganic Carbon ◽  
Major Ions ◽  
Kara Sea ◽  
Total Alkalinity ◽  
Shirshov Institute ◽  
Arctic Water ◽  
Total Contribution ◽  
Continental Runoff

<p>The Kara Sea receives about 55 % of the total continental runoff to the Siberian Arctic. Water of the Yenisei and Ob Rivers with low salinity (mineralization), flowing into the sea, forms a surface desalinated layer. The desalinated layer spreads over the sea area under the influence of hydrological and meteorological factors. Meltwater generated by the melting of marine and riverine ice and precipitation contribute to the formation of a surface desalinated layer along with continental runoff.</p><p>Determining the amount of fresh water is not accurate enough if only the salinity of surface water is considered. It is possible to identify riverine water and meltwater using hydrochemical proxies. The ratio of the major ions in seawater differs from that in riverine and meltwater. River waters are characterized by an increased content of silicate and reduced values of total alkalinity. At the same time, it is possible to identify the waters of the Ob and Yenisei Rivers by the estimated values of the total alkalinity and dissolved inorganic carbon obtained during the research expeditions to the Kara sea from 1993 to 2020.</p><p>The calculation of the parts of waters of different origin is done as a result of solving a system of equations. It includes the salinity and alkalinity values of the observed surface waters and those presumably involved in the mixing process. The salinity and alkalinity values of meltwater are taken as 0 and 134 µM respectively.</p><p>The total contribution of the Ob and Yenisei runoff ranges from 20 to 90% as it approaches the estuarine areas. The correlation coefficient between the proportion of river water and the salinity of the surface layer is quite high, it is equal to -0.9. This characterizes the inverse linear relationship. The separate contribution of the waters of the Yenisei differs from the contribution of the waters of the Ob, which is related to the hydrological conditions of the rivers.</p><p>The contribution of meltwater to the formation of the surface layer of the Kara Sea did not exceed 20%, with the exception of the coastal zone of the Novaya Zemlya. In this coastal zone, meltwater provides the greatest contribution compared to the other sources, which is associated with glacial runoff.</p><p>The work is implemented in the framework of the state assignment of the Shirshov Institute of Oceanology RAS (theme No. 0149-2019-0008), with the support of the Russian Scientific Foundation (project № 19-17-00196) and the grant of President of Russian Federation № MK-860.2020.5.</p>

scholarly journals Methane Content in Ground Ice and Sediments of the Kara Sea Coast

Geosciences ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 434 ◽  
Author(s):  
Irina Streletskaya ◽  
Alexander Vasiliev ◽  
Gleb Oblogov ◽  
Dmitry Streletskiy
Keyword(s):  
Active Layer ◽  
Kara Sea ◽  
Methane Content ◽  
The Arctic ◽  
Permafrost Degradation ◽  
Microbial Oxidation ◽  
Ground Ice ◽  
Arctic Seas ◽  
Methane Concentrations ◽  
Sea Coast

Permafrost degradation of coastal and marine sediments of the Arctic Seas can result in large amounts of methane emitted to the atmosphere. The quantitative assessment of such emissions requires data on variability of methane content in various types of permafrost strata. To evaluate the methane concentrations in sediments and ground ice of the Kara Sea coast, samples were collected at a series of coastal exposures. Methane concentrations were determined for more than 400 samples taken from frozen sediments, ground ice and active layer. In frozen sediments, methane concentrations were lowest in sands and highest in marine clays. In ground ice, the highest concentrations above 500 ppmV and higher were found in massive tabular ground ice, with much lower methane concentrations in ground ice wedges. The mean isotopic composition of methane is −68.6‰ in permafrost and −63.6‰ in the active layer indicative of microbial genesis. The isotopic compositions of the active layer is enriched relative to permafrost due to microbial oxidation and become more depleted with depth. Ice-rich sediments of Kara Sea coasts, especially those with massive tabular ground ice, hold large amounts of methane making them potential sources of methane emissions under projected warming temperatures and increasing rates of coastal erosion.

scholarly journals Geochemical properties of the water–snow–ice complexes in the area of Shokalsky glacier, Novaya Zemlya, in relation to tabular ground-ice formation

2005 ◽  
Vol 42 ◽  
pp. 249-254 ◽  
Author(s):  
M.O. Leibman ◽  
S.M. Arkhipov ◽  
D.D. Perednya ◽  
A.S. Savvichev ◽  
B.G. Vanshtein ◽  
...  
Keyword(s):  
Barents Sea ◽  
Climatic Conditions ◽  
Kara Sea ◽  
Ice Formation ◽  
Geochemical Data ◽  
Ground Ice ◽  
Novaya Zemlya ◽  
Geochemical Properties ◽  
Glacier Ice ◽  
Structural Aspects

AbstractTabular (massive) ground ice in periglacial areas of the Russian Arctic (Barents and Kara Sea coasts) is considered to be a remnant of past glacial epochs and is thus used as proof of the glacial extent. In this paper, we argue that the origin of these tabular ice bodies, which can be used as archives of specific climatic conditions and periglacial environments, is intra-sedimentary (migration/intrusion). The objective of this study is to establish geochemical benchmarks describing the ice formation from atmospheric moisture and compare them with geochemical data of tabular ground ice. Shokalsky glacier on Novaya Zemlya (NZ), on the east coast of the Barents Sea, was chosen as a possible moisture source for the formation of tabular ground ice at the key section ‘Shpindler’ on Yugorsky peninsula, on the south coast of the Kara Sea. Tabular ice in the Shpindler section was compared to the Shokalsky glacier ice in both isotope/geochemical and structural aspects. In general, the hydrochemical properties of glacier ice at NZ and ground ice from Shpindler are closely correlated, while stable-isotope, microelemental and microbiological properties are substantially different. It was concluded that glacier ice most likely participated in the formation of tabular ground ice, but only as a source of refrozen meltwater.

Zoya Il'inichna Glezer – life and scientific achievements

2019 ◽  
pp. 318-323
Author(s):  
Zinaida V. Pushina ◽  
Galina V. Stepanova ◽  
Ekaterina L. Grundan
Keyword(s):  
Western Siberia ◽  
Kara Sea ◽  
European Russia ◽  
Great Contribution ◽  
The South ◽  
The Creation ◽  
The 1960S ◽  
Scientific Achievements ◽  
South Of European Russia

Zoya Ilyinichna Glezer is the largest Russian micropaleontologist, a specialist in siliceous microfossils — Cenozoic diatoms and silicoflagellates. Since the 1960s, she systematically studied Paleogene siliceous microfossils from various regions of the country and therefore was an indispensable participant in the development of unified stratigraphic schemes for Paleogene siliceous plankton of various regions of the USSR. She made a great contribution to the creation of the newest Paleogene schemes in the south of European Russia and Western Siberia, to the correlations of the Paleogene deposits of the Kara Sea.

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