Unusual features of organic matter composition of bottom sediments from nearshore Komsomolets island area (on the data of sedimentary n-alkanes distribution)

Semenov P., Malyshev S., Gusev Е.

UNUSUAL FEATURES OF ORGANIC MATTER COMPOSITION OF BOTTOM SEDIMENTS FROM NEARSHORE KOMSOMOLETS ISLAND AREA

(on the data of dedimentary n-alkanes distribution)

Relief and Quaternary deposits of the Arctic, Subarctic and North-West Russia. Issue 5.

doi:10.24411/2687-1092-2019-10509

VNIIOkeangeologia, Saint-Petersburg, Russia

Abstract. This study is based on sampling data obtained during the expedition carried out by VNIIOkeangeologia in 2017 in the north of the Kara and Laptev seas under the Program of State geological mapping of the territory and continental shelf of the Russian Federation. In bottom sediments of the sampling area located between Komsomolets Island (Severnaya Zemlya) and Voronin Though we discovered unusual distribution pattern of n-alkanes remarkable for rare predominance of the peaks С₁₄, С₁₆, С₁₈ accompanied by minor input of С₂₅-С₃₃ series. Carbon isotope measurements (CSIA) revealed the values of δ¹³С lay within a range from -34 -to-31‰ evident of the common for all the compounds origin related to terrigenous vascular plants vegetation. Probably there were favorable conditions for vascular plants vegetation in the adjacent inland area. While the molecular composition features of n-alkanes indicate the deposition conditions causing untypical scenario of post-depositional OM transformation.

Keywords: bottom sediments, Kara Sea, organic matter, n-alkanes

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Cite this article:

Semenov P., Malyshev S., Gusev Е. Unusual features of organic matter composition of bottom sediments from nearshore Komsomolets island area (on the data of sedimentary n-alkanes distribution) // Relief and Quaternary deposits of the Arctic, Subarctic and North-West Russia. 2019. Issue 5. P. 43-46. doi:10.24411/2687-1092-2019-10509