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Dystrybucja biomarkerów i dojrzałość termiczna materii organicznej w tonsteinie i węglu kamiennym z pokładu 385/2 z kopalni Bogdanka (Lubelskie Zagłębie Węglowe)

Gola M. R., Karger M., Gazda L.

Przegląd Geologiczny

2011

Vol. 59, nr 12

777-784

The paper presents results of geochemical analyses of organic matter (OM) in a tonstein bed and surrounding bituminous coal from the Upper Carboniferous (Westphalian B) coal seam no. 385/2 from the Bogdanka mine, Lublin Coal Basin. In all studied samples, including those of tonstein and bituminous coal, OM was found to be very similar in composition. Distribution of hydrocarbons in investigated rocks is characterized by strong predominance with odd-number carbon-atom of the long-chain n-alkanes in comparison to the even-number and high concentration of C29 steranes, what implies relatively high input of higher-plant OM in these samples. Minor concentration of C28 steranes and perylene points at presence of fungi. In all extracts, the tri- and tetracyclic diterpanes co-occur with their aromatized derivatives, what suggests presence of the tap resin species - precursors of the conifer families in the plant community. The abundance of sesquiterpanes, pentacyclic triterpanes and benzohopanes indicates a significant bacterial input, most possibly connected with bacterial activity after deposition of terrestrial OM. The original material of tonstein was pyroclastic in orgin, and deposited directly on plants living at the surface of a mire. That material hadn’t had any direct influence on chemicalOMtransformation. The biomarker data, both for coals and tonstein, reveals that sedimentary organic matter was heated up to a temperature corresponding to the level of immature/start of oil window. On the other hand, the increase in thermal maturity value, based on distribution of the aromatic hydrocarbons in organic matter in tonstein (theoretical vitrinite values - Rc, Rcs) are probably due to the presence of incompletely burned organic remains (charcoals), transported to the sedimentary basin along with volcanic ashes.

Preliminary suggestions on the Pleistocene palaeovegetation around the Biśnik Cave (Częstochowa Upland, Poland) based on studies of molecular fossils from cave sediments

Krajcarz M. T. M. T., Gola M. R., Cyrek K. J. K. J.

Studia Quaternaria

2010

Vol. 27

55-61

Bisnik Cave is an important site of Middle Palaeolithic, with the longest sequence of Neanderthal settlement phases in Central Europe. In the previous studies of the Bisnik sediments, different elements of palaeoenvironment in the periods of Neanderthal occupation have been recognised, except of palaeovegetation, which could not be derived because of lack of preserved plant micro- or macrofossils. The current work is an attempt to reconstruct palaeovegetation in vicinity of the Bisnik Cave, using analysis of composition of plant-derived n-alkanes, preserved in sediments. In our study, we analyzed one sample from each of the sediment's layers 11 - 19c (early Late Pleistocene and late Middle Pleistocene). Abundant n-alkanes (mostly n-C27, n-C29 and n-C31) were found in all the sampled layers except for the layers 12, 16 and 19d, showing no alkanes at all. There is clear diversification of n-alkanes composition and cpr (carbon preference index) values between layers. Analysis of this composition, allows us to claim that the layers 11 and 14 were accumulated when the cave's vicinity was covered by dense coniferous forests, hence upon warm climate. The layers 19, 19a lower, 19b and 19c, presumably originated during cold periods when open woodlands or grasslands dominated. The other analyzed layers could be counected with intermediate vegetation in form of open woodland. However, not all of the achieved results stay in compliance with the actual stratigraphy, established basing on lithological data and palaeoecology offossil fauna, and we hope that explanation of this discrepancy would be possible after more extensive studies of molecular fossils are done.