Results from ikaite investigations in the Kara Sea ...

• Main Authors: Kodina, Ludmilla A, Tokarev, V G, Vlasova, Ludmilla N, Korobeinik, G S
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2003
• Subjects: Siberian River Run-Off SIRRO; Kara Sea
• Online Access: https://dx.doi.org/10.1594/pangaea.804557; https://doi.pangaea.de/10.1594/PANGAEA.804557

The authigenic carbonate mineral ikaite is specific of low-temperature high latitude environments. The depletion of ikaite carbon in 13C isotopes in most cases implies a causal relation of ikaite generation with methane geochemistry. In this paper we present new data on ikaite minerals in Holocene sediments sampled along the Yenisei channel at the southern (74°N) and northern (77°N) ends. Stable carbon isotopes of the ikaite crystals were studied in conjunction with the hydrochemistry and isotope geochemistry of the sediments. Pore water and natural gas samples were separated from sediments to describe the methane carbon isotope distribution pattern throughout two sedimentary sequences embedding the ikaite crystals of different isotope composition (-24 per mil and -42 per mil). The biogenic nature of the methane is indicated by 51 C values being as low as -104.4 per mil. In the case of the moderately depleted sample (-24 per mil) from the southern location the small-scale ikaite formation fits best into the ... : Supplement to: Kodina, Ludmilla A; Tokarev, V G; Vlasova, Ludmilla N; Korobeinik, G S (2003): Contribution of biogenic methane to ikaite formation in the Kara Sea: evidence from the stable carbon isotope geochemistry. In: Stein, R; Fahl, K; Fütterer, D K; Galimov, E M & Stepanets, O V (eds.), Siberian River Run-off in the Kara Sea: Characterisation, Quantification, Variability, and Environmental Significance, 488 pp. Proceedings in Marine Sciences, Elsevier, Amsterdam, 6, 349-374 ...