Grain Size Distribution of the Surface Layer of Bottom Sediments in the Barents Sea

The distribution of lead, zinc, and chromium in fractions of bottom sediments in the Narew River and its tributariesThe purpose of the paper was to evaluate the distribution of lead, zinc and chromium contents in different grain fractions of bottom sediments in the Narew River and some of its tributaries. This study also aimed to determine which fractions are mostly responsible for bottom sediment pollution. The studies of the Narew and its tributaries (the Supraśl, Narewka, and Orlanka) were conducted in September 2005 in the upper Narew catchment area. The analyzed bottom sediments differed regarding grain size distribution. The studies revealed the influence of the percentage of particular grain fractions present on the accumulation of heavy metals in all bottom sediments.

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Grain size distribution, clay mineralogy and chemistry of bottom sediments from the outer Thermaikos Gulf, Aegean Sea, Greece

Mediterranean Marine Science ◽

10.12681/mms.209 ◽

2004 ◽

Vol 5 (1) ◽

pp. 43

Author(s):

K.G. PEHLIVANOGLOU ◽

G. TRONTSIOS ◽

A. TSIRAMBIDES

Keyword(s):

Grain Size ◽

Size Distribution ◽

Clay Minerals ◽

Grain Size Distribution ◽

Bottom Sediments ◽

Clay Mineralogy ◽

Aegean Sea ◽

Wide Range ◽

Differential Settling ◽

Interstratified Phase

The Thermaikos Gulf constitutes the NW part of the North Aegean Sea and is limited eastward from the Chalkidiki Peninsula and westward from the Pieria Prefecture. Its plateau covers an area of 3,500 km2. The mechanisms responsible for the grain size distribution into the Gulf, the clay mineralogy and the chemistry of some bottom sediments from the outer Thermaikos Gulf, are examined. Source mixing during transportation, flocculation, differential settling processes and organic matter appear to be the main mechanisms for the distribution of clay minerals in shallow waters. All grain size fractions studied present a wide range of values confirming the extreme variations of the discharged load and the variability in marine processes. Plagioclases predominate over K-feldspars, while quartz is the most abundant mineral present. In addition, micas, chlorites, amphiboles and pyroxenes exist as primary and/or accessory minerals in all samples. Among clay minerals, illite predominates over smectite and smectite over chlorite (+ kaolinite). The ordered interstratified phase of I/S, with 30-35% S layers, is present in the 2-0.25µm fraction. The randomly interstratified phase of I/S, with 50% S layers, is present in the <0.25& micro; m fraction. On average the clay mineral content of the studied samples is: 48% I, 23% S, 17% Ch (+K) and 12% others for the 2-0.25µm fraction and 50% I, 30% S and 20% Ch (+K) for the <0.25 µm fraction. All these minerals are the weathering products of the rocks from the drainage basins of the rivers flowing into the Gulf, as well as of the Neogene and Quaternary unconsolidated sediments of the surrounding coasts. The terrigenous input, the water mass circulation and, to a lesser extent, the quality of the discharged material and the differential settling of grains, control the grain size distribution within the outer Thermaikos Gulf. The chemical composition of the analysed samples is generally in agreement with their mineral composition and signifies their terrigenous origin presenting discretely clastic character.

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GRAIN SIZE DISTRIBUTION AND TRANSPORTATION TRENDS OF BOTTOM SEDIMENTS IN THE SAND RIDGE FIELD OF THE SOUTH YELLOW SEA, CHINA

Marine Geology & Quaternary Geology ◽

10.3724/sp.j.1140.2012.06001 ◽

2013 ◽

Vol 32 (6) ◽

pp. 1-8 ◽

Cited By ~ 5

Author(s):

Rong WANG ◽

Yongzhan ZHANG ◽

Fei XIA ◽

Shandao ZHAO

Keyword(s):

Grain Size ◽

Size Distribution ◽

Grain Size Distribution ◽

Bottom Sediments ◽

Yellow Sea ◽

Sand Ridge ◽

South Yellow Sea ◽

The South ◽

The South Yellow Sea

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Hydrocarbons in waters and bottom sediments Of the Barents sea

10.29006/978-5-6045110-0-8/(35) ◽

2021 ◽

pp. 531-547

Author(s):

I.A. Nemirovskaya ◽

◽

A.M. Titova ◽

A.V. Khramtsova ◽

◽

...

Keyword(s):

Organic Matter ◽

Surface Layer ◽

Organic Carbon ◽

Bottom Sediments ◽

Suspended Matter ◽

Biochemical Composition ◽

Barents Sea ◽

Oil Pollution ◽

Early Summer ◽

The Barents Sea

Hydrocarbons in water, suspended matter and bottom sediments of the Barents Sea were studied based on materials from expeditions to the RV Akademik Mstislav Keldysh in 2016–2019. It is shown that at present there is no oil pollution in open areas of the Barents Sea. With the transition from early summer (2019) to autumn (2016), there was a decrease in hydrocarbon concentrations in surface waters, caused by a change in the biochemical composition of organic matter (possibly due to a decrease in the area of ice). With depth, the HC content decreased mainly. An exception was observed in the area of gutters and deposits, where in the bottom nepheloid layers there was an increase in the concentration of hydrocarbons in suspension and in the surface layer of bottom sediments, and in the thickness of the sediments there was no dependence on their distribution and organic carbon.

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