Geochemical Characteristics of Hydrocarbons in Core Sediments From the Southwest Sub-Basin of the South China Sea and Its Implications for the Sedimentary Environment

Marine sediments are found to record various information for example the evolution of ocean and exchange matter energy between surrounding continents oceans. The Southwest Sub-basin is one most important tectonic unit in South China Sea Basin. geochemical provides potential understand sedimentary history Sea. In this paper, aliphatic hydrocarbon compounds two core from sub-basin were analyzed using lipid biomarker analysis. average concentration total organic carbon (TOC) nitrogen (TN) both sediment A B similar, falling range 0.64% ± 0.18 0.10% 0.02%, respectively. C/N ratios vary 3.2 11.1, reflecting that was a mixture terrestrial marine sources with more contributions than A. long-chain n -alkanes show an even-odd predominance, higher plants short-chain plankton or bacteria. Pr/Ph 0.3–0.5 0.2–0.4, respectively, which far less 1, indicating environment dominated by strong reduction long-term stability. odd-even distribution medium-chain ( -C 14–20 ) due -fatty acids odd dominance strongly reductive depositional environment.