scholarly journals The Study of Uranium Accumulation in Marine Bottom Sediments: Effect of Redox Conditions at the Time of Sedimentation

Geosciences ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 332
Author(s):  
Nadezhda Khaustova ◽  
Yulia Tikhomirova ◽  
Svetlana Korost ◽  
Elena Poludetkina ◽  
Andrey Voropaev ◽  
...  
Keyword(s):  
Bottom Sediments ◽  
White Sea ◽  
Uranium Content ◽  
Black Shales ◽  
Redox Conditions ◽  
Source Rocks ◽  
Shelf Zone ◽  
The Black Sea ◽  
The White Sea ◽  
Run Off

To evaluate the effect of redox conditions at the sedimentation stage on uranium content and U/TOC ratio in marine source rocks, we analyzed the accumulation of uranium in modern marine bottom sediments formed in different redox conditions. The behavior of uranium from bottom sediments formed in oxidizing and sub-oxidizing settings has been studied on the sediments of the Upper Pleistocene–Holocene age accumulated in the coastal area of the White Sea (Kandalaksha Gulf). We studied the content of uranium, Eh, pH, TOC, C, H, N, and S element and isotope compositions and other parameters in two sampled columns of bottom sediments at a depth of 0–2.5 m. The composition of sediments was typical for the shelf zone where marine genesis mixes with the continental run-off. The upper layer of sediments (0–50 cm) were characterized by oxidizing conditions (Eh ~ 400 mV); with the increase in depth, redox conditions changed from oxidizing to reducing (0 ÷ 200 mV). The uranium concentration in the upper layer was 1–1.5 ppm, U/TOC ratio varied in the range of 0.8–1.1 ppmU/%TOC. The uranium content and U/TOC ratio increased up to the values of 2.6 ppm and 1.4 ppmU/%TOC at a depth of 0.5−2.5 m, respectively, but the general content of uranium in the studied environment was close to the values characterizing continental run-off. The results obtained for the White Sea sediments were compared with the sediment of the Black Sea, formed in the anoxic conditions of hydrogen sulfide contamination. In these conditions, the uranium content varied from 10 to 20 ppm. The obtained data were interpreted using thermodynamic modeling of the uranium forms in the seawater at different pH and Eh. This study demonstrated that the change of redox conditions from oxidizing to reducing leads to increased uranium content due to a decrease in uranium’s solubility in water. These results show that oxidation–reduction potential could be one of the most important factors controlling uranium content in black shales formed in the marine environment.

Occurrence Forms of Heavy Metals in the Bottom Sediments of the White Sea

2018 ◽  
pp. 241-270 ◽  
Author(s):  
Liudmila L. Demina ◽  
Dmitry F. Budko ◽  
Alexander N. Novigatsky ◽  
Tatiana N. Alexсeeva ◽  
Anastasia I. Kochenkova
Keyword(s):  
Heavy Metals ◽  
Bottom Sediments ◽  
White Sea ◽  
The White Sea

Comparative analysis of the microelemental composition of seston and bottom sediments in the White Sea

2006 ◽  
Vol 406 (1) ◽  
pp. 136-140 ◽  
Author(s):  
G. A. Leonova ◽  
V. A. Bobrov ◽  
V. P. Shevchenko ◽  
A. A. Prudkovskii
Keyword(s):  
Comparative Analysis ◽  
Bottom Sediments ◽  
White Sea ◽  
The White Sea ◽  
Microelemental Composition

scholarly journals Sensitivity of the coupled model of the White Sea dynamics and biochemistry

2015 ◽  
Vol 2 ◽  
pp. 82
Author(s):  
Ilya Chernov ◽  
Alexey Tolstikov
Keyword(s):  
White Sea ◽  
Coupled Model ◽  
Initial Distribution ◽  
The Arctic ◽  
Boundary Values ◽  
The White Sea ◽  
Thermal Dynamics ◽  
Software Complex ◽  
Long Run ◽  
Run Off

<p class="R-AbstractKeywords"><span lang="EN-US">The JASMINE model based on the prof. N.G. Iakovlev's model of the Arctic Ocean (FEMAO) is the software complex for simulating hydrodynamics and thermal dynamics of a sea; we use the White Sea as an example and also have tried to model other seas. JASMINE allows coupling with special purpose blocks, such as data assimilation or simulation of the sea ecosystem. For that we chose the mature BFM model of pelagic sea biochemistry. An important question is sensitivity of the model with respect to the outer forcing, such as synoptic data (air temperature and pressure, cloud cover, precipitation, wind), boundary values on liquid boundaries, river run-off, initial distributions of the tracers. The White Sea is a convenient model region for such investigation because of dominating tides; thus boundary values become important, while initial distribution is expected not to influence on the results in the long run, at least. The biochemical system also depends on the boundary conditions strongly, and also reacts on the forcing variations. We describe the response of the sea subsystems to different variations of forcing, show what values are crucial and what is not important.</span></p>

BOTTOM SEDIMENTS OF LAKES AND STREAMS OF DVINA BAY OF THE WHITE SEA COASTAL AREAS AS AN INDICATOR OF ANTHROPOGENIC IMPACT (BY THE EXAMPLE OF MERCURY POLLUTION) _

2017 ◽  
Author(s):  
Boris Krasnoyarskiy ◽  
Boris Krasnoyarskiy ◽  
Asya Ovsepyan ◽  
Asya Ovsepyan ◽  
Yury Fedorov ◽  
...  
Keyword(s):  
Bottom Sediments ◽  
Anthropogenic Impact ◽  
White Sea ◽  
Mercury Content ◽  
Mercury Pollution ◽  
Scientific School ◽  
The White Sea ◽  
Subarctic Region ◽  
Low Concentrations ◽  
Surrounding Areas

The article analyzes the data of expedition studies conducted by the team of the leading scientific school of Professor Fedorov Yu.A. in the Archangelsk region for more then 10-years period of researches. The materials of mercury content obtained for samples of bottom sediments sampled in the mouth area of the Northern Dvina River, the lakes of Arkhangelsk and the surrounding areas, at Dvina Bay and different areas of the White Sea. Based on the available data and having considered the results of the authors working on the subject of mercury pollution in the subarctic region, conclusions about the level of anthropogenic impact on water bodies and streams of the Arkhangelsk region are justified. Factors that contribute to the formation of relatively high and low concentrations of mercury in sediments identified. The effects of mechanical, hydrochemical, hydrological barriers analyzed. The natural background of mercury in the bottom sediments of the region revealed. Comparative analysis of the accumulation of mercury in the bottom sediments of the study area and other parts of the subarctic region realized. Opportunities and conditions for existence of the effect of "secondary pollution" discussed.

Lithology, biostratigraphy, and geochronology of the late pleistocene-holocene sediments on the coast of Onega bay of the White sea

2019 ◽  
Vol 485 (2) ◽  
pp. 221-225
Author(s):  
V. V. Kolka ◽  
O. P. Korsakova ◽  
N. B. Lavrova ◽  
T. S. Shelekhova ◽  
N. E. Zaretskaya
Keyword(s):  
Late Pleistocene ◽  
Bottom Sediments ◽  
Radiocarbon Dating ◽  
White Sea ◽  
The White Sea ◽  
Southeastern Part ◽  
Sedimentary Sequences ◽  
Onega Bay ◽  
Holocene Sediments ◽  
Sea Coast

This paper reports on the lithological, micropaleontological, and chronometric data (radiocarbon dating) for one of the areas of the White Sea coast. The sedimentary sequences were studied in the current lake basins, which were separated from the large basin at different times. The basin was situated in the head of the current Onega Bay. On the basis of these data, the bottom sediments were stratified and the Late Pleistocene-Holocene paleogeographic settings were reconstructed for the southeastern part of Onega Bay.

scholarly journals Art. XI.—The Avâr Language

1881 ◽  
Vol 13 (3) ◽  
pp. 291-352
Author(s):  
Cyril Graham
Keyword(s):  
Black Sea ◽  
White Sea ◽  
The Black Sea ◽  
The White Sea

In the year 1873, having traversed Russia from Archangel to Astrakhan, from the White Sea to the borders of the Kaspian, my friend and I determined to pass homewards through Daghistân and Georgia, and thence by the Black Sea to Odessa.

Partitioning of trace elements in the process of early diagenesis of bottom sediments in the White Sea

2017 ◽  
Vol 55 (1) ◽  
pp. 144-149 ◽  
Author(s):  
L. L. Demina ◽  
D. F. Bud’ko ◽  
T. N. Alekseeva ◽  
A. N. Novigatsky ◽  
A. S. Filippov ◽  
...  
Keyword(s):  
Trace Elements ◽  
Bottom Sediments ◽  
White Sea ◽  
Early Diagenesis ◽  
The White Sea
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