Composition of lipids from the First Lusatian lignite seam of the Konin Basin (Poland): relations to vegetation, climate and carbon cycling during the mid-Miocene Climatic Optimum 1 2 3 A. Bechtel , M. Widera , M. Woszczyk 1 Applied Geosciences & Geophysics, Montanuniversität Leoben, Peter-Tunner-Strasse 5, A-8700 Leoben, Austria 2 Adam Mickiewicz University, Institute of Geology, 12 Krygowski Street, 61-680 Poznań, Poland 3 Adam Mickiewicz University, Laboratory of Biogeochemistry,10 Krygowski Street, 61-680 Poznań, Poland The positive correlation between d13C and di-/(di + tri-)terpenoid ratios of lignite indicates the role of varying gymnosperm/angiosperm contributions on the carbon isotopic composition (Fig. 7). The C- isotope data of long-chain n-alkanes, diterpenods, and angiosperm- derived triterpenoids show parallel fluctuations within the profiles, arguing for the role of minor variations in d13C of atmospheric CO2 on d13C of plant lipids during the Mid-Miocene Climatic Optimum (Fig. 8). However, the influence of local variations in ambient CO2 (e.g., the canopy effect) cannot be excluded. Fluctuations in d13C values of individual compounds may also be related to changes in humidity, air temperature, and carbon cycling within the peat (Fig. 8). Geological Setting and Samples The Adamów, Jóźwin IIB and Tomisławice lignite mines cover fault-bounded, relatively shallow tectonic depressions. They are located ~20–35 km of Konin in central Poland (Fig. 1a). The Grey Clays Member of the Miocene Poznań Fm. contains the examined First Lusatian lignite seam. It is up to several meters thick, on average 6.3–8.1 m (Fig. 1b-d). The seam formed in the middle part of the mid-Miocene (~15 Ma), during the last peak of the mid-Miocene Climatic Optimum. Acknowledgement: This poster, presented at the EGU General Assembly 2020 in Vienna, is a contribution to the Research Project No. 2017/27/B/ST10/00001, funded by the National Science Centre, Poland. Bulk geochemistry and molecular composition of lipids Bulk geochemistry and molecular composition of lipids Sample AD-02 Hydrocarbons (F1) 30 35 40 45 50 55 60 65 70 75 80 85 90 Time (min) 0 10 20 30 40 50 60 70 80 90 100 Relative Abundance Std. 23 25 Dehydroabietane Simonellite a-Phyllocladane b-Phyllocladane Pimarane Isonorpimarane Norpimarane Isopimaradiene des-A-Lupane des-A-Oleanenes 27 29 31 Dinoroleana-tetraene Dinorlupa-triene ab-C31-Hopane (22R) bb-C31-Hopane des-A-8,14-seco-noroleana-pentaene a) Cadalene 19 C30 Hop-17(21)-ene Alcohols (F3) 30 35 40 45 50 55 60 65 70 75 80 85 90 Time (min) 0 10 20 30 40 50 60 70 80 90 100 Relative Abundance C24 n-Alkanol C26 n-Alkanol C28 n-Alkanol C22 n-Alkanol Std. C18 n-Alkanol C16 n-Alkanol C14 n-Alkanol C12 n-Alkanol C23 n-Alkanol C25 n-Alkanol Campesterol b-Sitosterol b-Amyrin a-Amyrin Lupeol Friedelin c) Carboxylic Acids (FA) 30 35 40 45 50 55 60 65 70 75 80 85 90 Time (min) 0 10 20 30 40 50 60 70 80 90 100 Relative Abundance C16:0 n-FA C16:1 n-FA C15:0 n-FA C15:0 i-FA C14:0 n-FA C12:0 n-FA C10:0 n-FA Std. C18:0 n-FA C18:1 n-FA C17:0 n-FA C17:0 i-FA C20:0 n-FA C22:0 n-FA C24:0 n-FA C26:0 n-FA C28:0 n-FA C30:0 n-FA C23:0 n-FA C25:0 n-FA C27:0 n-FA C21:0 n-FA Hopanoic acids d) Ketones + PAHs (F2) 30 35 40 45 50 55 60 65 70 75 80 85 90 Time (min) 0 10 20 30 40 50 60 70 80 90 100 Relative Abundance Std. Dehydroferruginol Ferruginol Labdan-15-oic acid, ME Retene 6,10,14 Trimethyl-pentadecan-2-one C25 n-Alkan-2-one C27 n-Alkan-2-one C29 n-Alkan-2-one C31 n-Alkan-2-one C29 n-Alkan-10-one Tetramethyl-octahydro-picenes C31 n-Alkan-16-one Squalene b) Trimethyl-dihydro-picene Friedelin C20 n-Alkanol Fig. 5: Total ion current chromatograms of the (a) hydrocarbon fraction, (b) the ketone fraction, (c) the alcohol fraction, and (d) the carboxylic acids obtained from the lignite sample AD-02, Std. = Internal Standard (deuterated tetracosane (F1), 1,1´-binaphthyl (F2), 1-nonadecanol (F3), nonadecanoic acid (FA), respectively). Fig. 6: Relative percentages of source specific plant lipids within the samples. Elevated ash yields and low sulfur contents indicate peat formation in topogenous mires under freshwater conditions (Figs. 2, 3, 4). The molecular composition of the extracted lipids is highly variable, including leaf-wax n-alkanes in the C23 to C31 range, diterpenoids, hopanoids, and angiosperm-derived triterpenoids, as well as saturated fatty acids, long-chain n-alkanols and n-alkan-2-ones (Figs. 2, 3. 4). The enhanced abundances of short-chain n-FAs in several lignite samples argue for the contribution of algae and microorganisms to the biomass during periods of raised water table. Low bb/(bb+ab) hopane ratios imply acidic conditions during peatification. High concentrations of plant wax derived lipids are found in samples of detrital lignite (Fig. 5). The relative abundances (Paq = 0.08–0.51; Figs. 2d, 3d, 4d) of mid-chain (C23, C25) n-alkanes argue for a minor contribution of macrophytes (graminoids, etc.), enhanced during periods of raised water level. Terpenoid biomarker ratios (Fig. 6) argue for mixed vegetation, including gymnosperms (i.e. conifers) and angiosperms. From the sesqui- and diterpenoids present in the lignite (Fig. 5), a significant contribution of species of the coniferales families Cupressaceae and Pinaceae is concluded. High relative abundances of triterpenoids of the oleanane and ursane structural types in several parts of the seam indicate angiosperm domination in the peat-forming vegetation (Fig. 6). The input from Betulaceae is suggested from the occurrence of lupeol and its derivatives. Stable Isotope Analyses Texture of lignite lithotypes: DL - detritic, XDL - xylodetritic, DXL - detroxylitic, WDL - weathered Structure of lignite lithotypes: m - massive, h - horizontal stratification, fr - fractured F - fines (silt and clay), S - sand - fractures (cleats) - horizontal stratification - xylites (fossilised wood) Adamów mine S DL XDL DXL F 61 62 63 64 65 66 67 68 AD-02 AD-03 AD-04 AD-05 AD-06 AD-07 AD-08 AD-09 AD-01 WDLm WDLm DXLm(fr) XDLm(fr) XDLm DLm AD-10 Jóźwin IIB mine S DL XDL DXL F 40 39 41 42 43 44 45 46 JD-01 JD-02 JD-03 JD-04 JD-05 JD-05 - sample position JD-06 JD-00 XDLm(fr) DLm(fr) DLm(fr) JD-07 47 Tomisławice mine S DL XDL DXL F TD-02 TD-03 TD-04 TD-05 TD-06 TD-07 TD-08 TD-09 TD-01 XDLm(fr) XDLh XDLm DXLm XDLh DLm DLm TD-10 First Lusatian lignite seam Grey Clays (Mid-Polish) Member Kozmin Formation Poznan Formation Wielkopolska Member 53 54 55 56 57 58 59 60 61 62 63 m a.s.l. sample sedimentary log m a.s.l. sample sedimentary log m a.s.l. sample lithostratigraphy sedimentary log POLAND Warsaw Poznan KONIN TUREK N 5 km 200 km Jóźwin IIB lignite deposit Tomisławice lignite deposit Adamów lignite deposit - studied section a) b) c) d) Fig. 1: (a) Location of the studied lignite opencast mines in the Konin Basin (Poland); and lignite lithotypes, structural elements, and position of detrital lignite samples in the profiles from the (b) Adamów, (c) Jóźwin IIB, and (d) Tomisławice opencast mines. Altitude (m a.s.l.) Adamów mine S DL XDL DXL F 61 62 63 64 65 66 67 68 AD-05 AD-06 AD-07 AD-08 AD-09 AD-01 WDLm WDLm DXLm(fr) XDLm(fr) XDLm DLm AD-10 sample sedimentary log AD-02 AD-03 AD-04 Altitude (m a.s.l.) Legend see Fig. 1 60 61 62 63 64 65 66 67 68 0 50 100 150 200 250 long-chain FAs short-chain FAs 60 61 62 63 64 65 66 67 68 0 25 50 75 100 Steroids Hopanoids 0 100 200 300 Diterpenoids Triterpenoids 0.0 0.2 0.4 0.6 0.8 1.0 0 10 20 30 unsat. FAs branched FAs a) b) c) 0 10 20 30 40 50 60 TOC, Ash (wt%) 0.0 0.5 1.0 1.5 TIC, S (wt%) 0 50 100 150 200 250 Conc. (mg/g TOC) TOC Ash TIC S n-Alkanes n-Alkan-2-ones n-Alkanols Conc. (mg/g TOC) Conc. (mg/g TOC) Di-/(Di- + Tri-)- terpenoids Conc. (mg/g TOC) Conc. (mg/g TOC) e) f) g) h) i) 0.0 0.2 0.4 0.6 0.8 1.0 Paq d) Fig. 2: Sampling position and variation of concentrations and concentration ratios of lipids within the First Lusatian lignite seam at the Adamów mine. TOC, Ash (wt%) TIC, S (wt%) Altitude (m a.s.l.) Jóźwin IIB mine S DL XDL DXL F 40 39 41 42 43 44 45 46 JD-01 JD-02 JD-03 JD-04 JD-05 JD-06 JD-00 XDLm(fr) DLm(fr) DLm(fr) JD-07 47 sample sedimentary log Altitude (m a.s.l.) Legend see Fig. 1 Conc. (mg/g TOC) Di-/(Di- + Tri-)- terpenoids Conc. (mg/g TOC) Conc. (mg/g TOC) Conc. (mg/g TOC) Conc. (mg/g TOC) 38 39 40 41 42 43 44 45 46 47 0 10 20 30 40 50 60 0.0 0.5 1.0 1.5 2.0 2.5 0 50 100 150 200 250 0 50 100 150 200 250 long-chain FAs short-chain FAs 38 39 40 41 42 43 44 45 46 47 0 25 50 75 100 Steroids Hopanoids 0 100 200 300 Diterpenoids Triterpenoids 0.0 0.2 0.4 0.6 0.8 1.0 0 5 10 15 20 unsat. FAs branched FAs TOC Ash TIC S n-Alkanes n-Alkan-2-ones n-Alkanols a) b) c) e) f) g) h) i) 0.0 0.2 0.4 0.6 0.8 1.0 Paq d) Fig. 3: Sampling position and variation of concentrations and concentration ratios of lipids within the First Lusatian lignite seam at the Jóźwin IIB mine. Altitude (m a.s.l.) Tomisławice mine Di-/(Di- + Tri-)- terpenoids Conc. (mg/g TOC) Conc. (mg/g TOC) Conc. (mg/g TOC) Conc. (mg/g TOC) S DL XDLDXL F TD-02 TD-03 TD-04 TD-05 TD-06 TD-07 TD-08 TD-09 TD-01 XDLm(fr) XDLh XDLm DXLm XDLh DLm DLm TD-10 53 54 55 56 57 58 59 60 61 62 63 sample sedimentary log Altitude (m a.s.l.) Legend see Fig. 1 51 52 53 54 55 56 57 58 59 60 61 62 63 0 20 40 60 80 0.0 1.0 2.0 3.0 0 200 400 600 0 100 200 300 400 long-chain FAs short-chain FAs 51 52 53 54 55 56 57 58 59 60 61 62 63 0 20 40 60 80 100 120 Steroids Hopanoids 0 50 100 150 200 Diterpenoids Triterpenoids 0.0 0.2 0.4 0.6 0.8 1.0 0 10 20 30 40 unsat. FAs branched FAs TOC Ash TIC S n-Alkanes n-Alkan-2-ones n-Alkanols Conc. (mg/g TOC) TOC, Ash (wt%) TIC, S (wt%) a) b) c) e) f) g) h) i) 0.0 0.2 0.4 0.6 0.8 1.0 Paq d) Fig. 4: Sampling position and variation of concentrations and concentration ratios of lipids within the First Lusatian lignite seam at the Tomisławice mine. 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 -26.5 -26.3 -26.1 -25.9 -25.7 -25.5 -25.3 -25.1 -24.9 -24.7 -24.5 Adamów Jóźwin IIB Tomisławice 13 C ( o / oo , PDB) d Di-/(Di- + Tri-)terpenoids Fig. 7: Cross-correlation of d13C of total organic carbon versus the ratios of diterpenoids to the sum of di- plus triterpenoids concentrations of lignite samples. S DL XDL DXL F 61 62 63 64 65 66 67 68 AD-05 AD-06 AD-07 AD-08 AD-09 AD-01 WDLm WDLm DXLm(fr) XDLm(fr) XDLm DLm AD-10 sample sedimentary log AD-02 AD-03 AD-04 Altitude (m a.s.l.) S DL XDL DXL F 40 39 41 42 43 44 45 46 JD-01 JD-02 JD-03 JD-04 JD-05 JD-06 JD-00 XDLm(fr) DLm(fr) DLm(fr) JD-07 47 sample sedimentary log Altitude (m a.s.l.) Adamów mine S DL XDLDXL F TD-02 TD-03 TD-04 TD-06 TD-07 TD-08 TD-09 TD-01 XDLm(fr) XDLh XDLm DXLm XDLh DLm DLm TD-10 53 54 55 56 57 58 59 60 61 62 63 sample sedimentary log Altitude (m a.s.l.) Legend see Fig. 1 TD-07 Tomisławice mine -32 -31 -30 -29 -28 -28 -27 -26 -25 -24 -30 -29 -28 -27 -26 13 C ( o / oo , PDB) d 13 C ( o / oo , PDB) d 13 C ( o / oo , PDB) d a) b) c) n-C23 n-C29 n-C31 Norabietane Pimarane a-Phyllocladane Ferruginol Monoarom. Oleanene Monoarom. Lupene Triarom. Oleanene Tetraarom. Oleanene -32 -31 -30 -29 -28 -27 -26 -25 -24 -30 -29 -28 -27 -26 13 C ( o / oo , PDB) d 13 C ( o / oo , PDB) d 13 C ( o / oo , PDB) d Jóźwin IIB mine n-C23 n-C29 n-C31 Norabietane Pimarane a-Phyllocladane Ferruginol Monoarom. Oleanene Monoarom. Lupene Triarom. Oleanene Tetraarom. Oleanene a) b) c) -32 -31 -30 -29 -28 -27 -26 -25 -24 -30 -29 -28 -27 -26 13 C ( o / oo , PDB) d 13 C ( o / oo , PDB) d 13 C ( o / oo , PDB) d a) b) c) n-C23 n-C29 n-C31 Norabietane Pimarane a-Phyllocladane Ferruginol Monoarom. Oleanene Monoarom. Lupene Triarom. Oleanene Tetraarom. Oleanene Fig. 8: Depth trends of carbon isotopic compositions of (a) C23, C29, and C31 n-alkanes, (b) diterpenoids, and (c) triterpenoids within the studied profiles.