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EN
The borings of Teredinidae in fossil wood of Taxodium distichum Gothan, 1906. Photographs of borings in fossil wood (Taxodium distichum Gothan, Miocene, Roztocze, Poland) were taken. The texture of the borings surface was analyzed. Moreover, photographs were taken of the surface texture of borings in makore wood (Tieghemella heckelii Pierre) from Africa after Teredinidae and after different species of insects in Scotch pine (Pinus sylvestris L.) for comparative purposes. The photographs were compared. The suspected wood borings in the studied fossil wood of T. distichum were made by mollusc (Teredinidae).
PL
Tunele Teredinidae w skamieniałym drewnie Taxodium distichum Gothan, 1906. Wykonano zdjęcia faktury powierzchni ściany tuneli wydrążonych przez Teredinidae w kopalnym drewnie Taxodium distichum z Frampola (Miocen, Roztocze, SE Polska). Dla celów porównawczych sfotografowano tekstury powierzchni ściany tuneli w drewnie makore (Tieghemella heckelii Pierre) z Afryki, pozostałe w sośnie zwyczajnej (Pinus sylvestris L.) po żerowaniu Teredinidae i innych gatunkach owadów. Na podstawie porównania fotografii stwierdzono, że tunel w badanym drewnie kopalnym T. distichum został wydrążony przez Teredinidae.
EN
Aromatic hydrocarbons are present in the fossil wood samples in relatively small amounts. In almost all of the tested samples the dominating aromatic hydrocarbon is perylene and its methyl and dimethyl derivatives. The most important biomarkers present in the aromatic fraction are dehydroabietane, siomonellite and retene, compounds characteristic for conifers. The distribution of discussed compounds is highly variable due to such early diagenetic processes affecting the wood as oxidation and the activity of microorganisms. MPI1 parameter values (methylphenanthrene index) for the majority of the samples are in the range of 0.1 to 0.5, which results in the highly variable values of Rc (converted value of vitrinite reflectance) ranging from 0.45 to 0.70%. Such values suggest that MPI1 parameter is not useful as maturity parameter in case of Middle Jurassic ore-bearing clays, even if measured strictly on terrestrial organic matter (OM). As a result of weathering processes (oxidation) the distribution of aromatic hydrocarbons changes. In the oxidized samples the amount of aromatic hydrocarbons, both polycyclic as well as aromatic biomarkers decreases.
EN
New collection of the Late Neogene woods from three localities was gathered during the geological field-trip in the Tainan' Peninsula during the last summer period. The first locality is situated in the north coast of the Taman' Peninsula, close to the town of Taman'. The deposits are represented by the thick clay layer of the Meotian regional stage. There was found single low-petrified trunk of the wood; which was located vertically to enclosing rocks. Petrified wood from the locality of the north coast is related to Angiosperms, due to the vessels discovered in the thin section during the investigation using scanning electron microscope (SEM) CAMSCAN. The second locality is situated on the south coast of Tainan' Peninsula, 2.5 km eastward the Gelezny Rog cape. There the monotonous clay layer has been intercalated by argillites. The age of the rocks has been determined to Pontian time interval. Low-petrified wood trunks of the conifers were vertically oriented in the layer. Third locality is situated near the Gelezny Rog cape. In the ferruginous sandstones of the Cimmerian regional stage, the coniferous fossil woods have been found. Two methods has been applied during the study of the wood remains - using standard SEM and microsections study. Volumetric anatomical structures of radial and tangential sections of the wood can be observed in SEM, but it is very difficult to install the cross wood section for SEM. There are six coniferous wood remains from two last localities, which were studied by using SEM. The preliminary fossil wood data from three new localities point to the presence of conifers such as Taxodioxylon and some of Angiosperms.
EN
Macroscopic observations, microscopic studies and literature data revealed that Middle Jurassic wood from Częstochowa area has a different state of preservation, and various types and degrees of mineralization and oxidation. Obtained results of organic matter fractionation illustrate a clear domination of polar fraction in the obtained extracts revealing low thermal maturity stage. Total organic carbon (TOC) values for analysed samples are in a wide range from 1.06% to 68.50%. The highest amount of TOC were measured in not or poorly mineralized wood samples but most of them are mineralized wood fragments, showing the TOC values in the range of 2% - 10%. Percentage content of carbonate in fossil wood constitute in a wide range from less than 1% CaCO3 to above 85% CaCO3. The resulting percentage of the total sulfur content is very varied and do not show convergence with other data such as TOC, carbonate content, etc and is most probable connected with pyritisation range. Unlike the Middle Jurassic clay samples, where long-chain and short-chain n-alkanes occur in similar concentrations, in wood samples always short-chain n-alkanes dominated, in the range from 15 to 23 carbon atoms in molecule. The values of the CPI are generally higher than 1 which indicates the contribution of organic matter derived from higher plant waxes, which are characteristic of e.g. needles from gymnosperm plants. Under the influence of postdiagenetic oxidation in mineralized wood samples distribution of n-alkanes is changing. Diaster-13(17)-enes with 28 and 29 carbon atoms in molecule are present in the wood samples, while those with 29 atoms strongly prevail.
PL
Makroskopowe obserwacje, mikroskopowe badania i dane literaturowe wykazały, że środkowojurajskie drewno z okolic Częstochowy ma różny stan zachowania oraz różne rodzaje i stopień mineralizacji oraz utlenienia. Uzyskane wyniki rozdziału frakcyjnego pokazują wyraźną przewagę frakcji polarnej w badanych ekstraktach. Wartości TOC dla badanych próbek wahają się w szerokim zakresie od 1,06% do 68,50 %. Największa ilość TOC występuje w nie zmineralizowanych lub słabo zmineralizowanych próbkach drewna. Większość próbek to zmineralizowane fragmenty drewna, pokazując wartości TOC w zakresie od 2% - 10%. Zawartość procentowa węglanów w badanych próbkach znajduje się w szerokim zakresie od mniej niż 1% CaCO3 do ponad 85% CaCO3. Procentowa zawartość siarki całkowitej jest bardzo zróżnicowana i nie wykazuje zbieżności z innymi danymi, takimi jak TOC czy zawartość węglanów, itp. W odróżnieniu od środkowojurajskich iłów, gdzie długołańcuchowe i krótkołańcuchowe n-alkany występują w podobnych stężeniach , w próbkach drewna zawsze przewyższają n-alkanów krótkołańcuchowe, występujące w zakresie od 15 do 23 atomów węgla w cząsteczce. Wartości wskaźnika CPI są generalnie wyższe niż 1, co wskazuje na udział materii organicznej pochodzącej z wosków roślin wyższych. Pod wpływem post-diagenetycznego utleniania zmineralizowanych próbek drewna zmienia się dystrybucja n-alkanów. W badanych próbkach obecne są diaster-13 (17)-enes o 28 i 29 atomów węgla w cząsteczce, natomiast te o 29 atomów znacznie przeważają.
EN
The Staffin Bay section in the Isle of Skye, UK is one of the most stratigraphically complete Oxfordian sections in Europe. This contribution presents the first high-resolution stable isotope record of this Middle Callovian to Early Kimmeridgian succession. The isotope record includes both terrestrial and marine data that were obtained from microscopic wood debris and belemnites respectively. The organic carbon-isotope record was derived from organic rich sediment samples taken almost entirely from the Staffin Shale Formation. This formation is largely represented by a series of isolated foreshore exposures dominated by mudrocks that were deposited in a predominantly offshore marine environment. Over 200 sediment samples were analysed from the 150 m section. The concurrent ä13C marine carbonate curve was produced using belemnites collected from the same formation. Approximately 200 belemnite horizons were sampled. The organic carbon-isotope data show a broad Lower to Middle Oxfordian positive carbon isotope excursion from the Mariae to Tenuiserratum Zone, with maximum values occurring in the Cordatum Zone. This is followed by a return to pre-excursion values continuing into the Early Kimmeridgian Cymodoce Zone. A brief negative excursion (of ~2‰) is also identified near the Densiplicatum-Tenuiserratum zones boundary. Rock-eval analysis confirms that the organic matter is predominantly terrestrial in origin. The concurrent ä13C marine carbonate curve derived from belemnites shows a broadly similar trend. This suggests that the positive carbon-isotope excursion recorded here may have affected the global carbon reservoir (i.e. the whole ocean-atmosphere system). The carbon-isotope record derived from this section appears to be generally consistent with Oxfordian Tethyan records (e.g. Wierzbowski 2002, 2004) and a preliminary study of the Staffin Bay area by Pearce et al. (2005).
EN
This article presents the results of anatomical and growth ring analyses of Badenian fossil wood from the Roztocze region. All the wood specimens examined are classified as Taxodioxylon taxodii Goth. The growth rings of these woods are very narrow, and they vary considerably in width. Tracheids have large diameters and thin cell walls.The latewood zone is wide; the transition between early and latewood is gradual. Both false and wedge rings and also reaction wood zones are often found. These characteristics of the fossil wood make it a suitable aid to reconstructing the environmental conditions prevailing while the trees were alive. The environmental requirements of these ancient Roztocze trees are interpreted by comparison with those of their nearest living relatives, with the conclusion that they lived in waterlogged or temporarily flooded stands under seasonally changing environmental conditions and with a long growing season. The climate was warm and humid and characterized by significant variability, mainly as regards the amount of precipitation.
7
Content available remote Mioceńskie drewno z Roztocza (Polska południowo-wschodnia)
PL
W artykule przedstawiono wyniki analizy anatomiczenej mioceńskiego drewna z obszaru Roztocza. Zsylifikowane drewno pochodzi z warstw badeńskich piasków kwarcowych. Jego mineralizacja przebiegała w środowisku wodnym, a źródłem roztworów krzemionkowych, wysycającym tkanki roślinne, był proces laterytyzacji. Badania struktury anatomicznej pozwoliły na zaklasyfikowanie drewna do gatunku Taxodioxylon taxodii Goth. Kopalne szczątki tych drzew są częstymi skamieniałościami, występującymi w średnich szerokościach geograficznych półkuli północnej. Oznaczenie przynależności systematycznej mioceńskiego drewna pozwoliło na przybliżenie znajomości warunków paleoklimatycznych Roztocza. Żyjącym odpowiednikiem gatunku T. taxodii jest cypryśnik błotny Taxodium distichum (L.) Rich. Wymagania klimatyczne i siedliskowe trzeciorzędowych drzew były zbliżone do tych, jakie posiadają współczesne cypryśniki. Cypryśnik, występujący na bagiennych obszarach południowo-wschodniej części Ameryki Północnej, rośnie najczęściej na terenach o klimacie ciepłym i wilgotnym. Zatem takie warunki mogły również istnieć w okresie trzeciorzędu na obszarze Roztocza.
EN
This article presents anatomical research of fossil wood from Roztocze. Silicified wood from this territory appears within Badenian quartz sand. Theirs mineralization followed at water environment and the source of silica solution, which impregnated wood tissue, was lateritic weathering. Anatomical analyses allowed to classify all samples to species Taxodioxylon taxodii Goth. Fossil remnants of this wood are common in middle latitude of northern hemisphere. Taxonomical classification of Miocene wood enabled to determine the palaeoclimatic conditions. Because the nearest living relative of this species is baldcypress Taxodium distichum (L.) Rich., climatic and stand requirements of Tertiary trees have to be similar to demands of living baldcypresses. Baldcypress which occur in wetland areas of south-eastern part of North America, most frequent overgrow territory with warm and humid climate. Therefore such conditions had to exist in Tetriary time in Roztocze region.
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