Differential transportation and deposition of terrestrial biomarkers in middle Eocene fluvial to estuarine environments, Hokkaido, Japan

Abstract

Higher plants constitute a significant portion of sedimentary organic matter in middle Eocene fluvial-floodplain-estuarine sedimentary rocks exposed in the Bibai region of central Hokkaido, Japan. The differential transportation and deposition of terrestrial biomarkers were studied in this area. The distribution of higher plant and fungal biomarkers in the Bibai non-marine sedimentary rocks was constrained by sedimentary facies and lithology.Claystones and siltstones lacking coaly fragments tended to be rich in angiosperm biomarkers, whereas coal and coaly mudstones were comparatively rich in gymnosperm biomarkers.Perylene, a possible fungal biomarker, was detected in fine-grained floodplain deposits.Facies and lithologic controls on terrestrial biomarker distribution can be attributed to the differential transportation and deposition of organic debris and degradation products derived from higher plants and fungi. Redox potential of the depositional environment is another important factor for the formation and preservation of terrestrial aromatic biomarkers.Reconstruction of land-based paleovegetation from terrestrial biomarkers in non-marine sediments requires careful consideration of the differential transportation and preservation of precursory terrestrial organic compounds.

Paleoenvironmental Settings of the Soma Coal Basin (Turkey): Insights from Maceral Data, Biomarker, and Carbon Isotopic Composition

“…Similarly, C/N ratios are also high, indicating high terrestrial vegetation. 55 Stable carbon isotopic (δ 13 C) values are an important tool used to determine the origin and differentiation of organic matter between different depositional environments, either marine or terrestrial. 56 − 59 The δ 13 C values of the samples of the KP1, KM3, and KM2 seam were between −24.97 and −27.52‰ ( Table 5 ), indicating that they are compatible with the material between the terrestrial C 3 type vegetation and the coal seen in Figure 7 a.…”

Investigation of the paleodepositional environment of the middle Miocene aged organic matter rich rocks (Tavas/Denizli/SW Turkey) by using biomarker parameters and stable isotope compositions (13C ve 15N)

“…As seen from the diagram δ 13 C-δ 15 N Tavas (Denizli / SW Turkey) clayey coal of paleo vegetation it is designated as C3 terrestrial ecosystem (Figure 8c) (Coplin and Shrestha, 2016). C / N ratios of samples (between 26.42 and 32.36) are greater than 10 and are characterized by high terrestrial plants (Table 3) (Inoue et al, 2012).…”