The present study discusses the outcome of palynlogical and palaeobotanocal investigations of Middle Jurassic strata of the Tabas Block. The most commonly identified spore type is a trilete spore, Klukisporites, which accounts for 30 per cent, and the genus Ischyosporites which makes up 12 per cent of the spore collection. Plant fossils recovered from the borehole studied are indicative of a varied assemblage, starting with a diverse range of ferns and followed by Cycadophytes, Ginkgophytes and Coniferophytes. The predominance of the Lowland group in the Tabas Block during the Bajocian–Bathonian, as indicated by the Sporomorph EcoGroup (SEG) and Plant EcoGroup (PEG) models, suggests that the strata studied were laid down mainly in a lowland environment. Dinoflagellate cysts were found in locations that correspond to river and coastal ecogroups, hinting at marine influence.
Current territory of Poland was an exploration area for paleontologists from other European countries throughout the almost entire nineteenth century. A considerable part of findings were stored in institutions located beyond current borders of Poland. We have examined, documented and identified above 350 fossils housed in the Natural History Museum in Vienna (Naturhistorisches Museum Wien). The collection includes paleobotanical and paleozoological specimens from the Little Poland and the Upper Silesia. Some of these specimens are a unique material from the localities which are no longer available.
The sample in the formof the drill core 9 cm long and 6 cm in diameter reveals exclusively secondary wood. No growth rings have been observed. Tracheids have the width 20–50 μm (mean 25 μm) in the tangential section. Pitting on the radial walls is mainly uniseriate, partly biseriate or triseriate. The uniseriate pits are circular or oval. The biseriate and triseriate pits are polygonal (often hexagonal), distributed adjacent to each other, and densely cover the whole width of the walls. The diameter of the pits is 12±2 μm. The poruses are circular. Medullary rays are mostly uniseriate, composed of 1–46 layers; mostly between a fifteen or so and 30 layers. As the investigations are at the preliminary stage, the author prefers to use only the generic term to name the wood, namely Dadoxylon sp., without giving it a species designation. Mineralogical investigation of silicified wood was conducted using polarizing light microscope. Observations showed various the optical orientation of quartz crystals filling up cells of wood. It is observed as differentiated disapperance of polarized light. This phenomenon documents that beginning of growth of quartz crystals (center of crystallization) was located at various places of cell walls. This situation is the result of beginning of destruction of organic compounds of wall structure of cells at various places. Additionally investigation documents various intensity of silification of cordaitalean structure. Because of this the process of silification is different at various parts of tissues and one can observe parts fully petrified and completely without mineralization. The structure of wood tissues is at same places damaged by crystallizing quartz. This phenomenon is observed at the tissues where silification was continued and size of newly formed quartz crystals is overgrowth size wood cells of wood. Mentioned zones of cell destruction are especially well seen at placed where silification developed parallel to orientation of biological wood structures. In summary one can say that mentioned processes were the reason of only partial petrification (silification) of examined cordaitalean second wood.
A charophyte gyrogonite assemblage consisting of Platychara cf. sahnii, Nemegtichara grambastii and Microchara sp. is reported herein from two localities (Bara Simla Hill and Chui Hill sections) of the Lameta Formation at Jabalpur. The Lameta Formation locally underlying the Deccan traps has been shown to be pedogenically modified alluvial plain deposits containing one of the most extensive dinosaur nesting sites in the world. They are associated with dinosaur bones and freshwater ostracod assemblages that suggest a Late Cretaceous (Maastrichtian) age. This is the first detailed systematic account of charophyte gyrogonites from the Lameta Formation. This charophyte assemblage is compatible with the biostratigraphic attribution provided by the ostracods. From a biogeographic viewpoint, it exhibits considerable similarity to other infratrappean assemblages of the Nand, Dongargaon, and Dhamni-Pavna sections (Maharashtra), and some intertrappean assemblages of Kora in Gujarat, Rangapur in Andhra Pradesh and Gurmatkal in South India. Globally, the genus Microchara is well distributed throughout Eurasia, whereas the genus Platychara occurs richly in the Upper Cretaceous deposits of Europe, Asia, America and Africa. However, at the specific level, Platychara cf. sahnii shows close affinities with charophytes from the Maastrichtian of Iran whilst Nemegtichara grambastii shows distinct affinities with two species of Early Palaeogene deposits of China and Mongolia. The presence of charophyte gyrogonites in the Lameta sediments is attributed to local lacustrine and palustrine conditions within a flood plain environment.
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Z perspektywy około 90 lat przedstawiono próbę scharakteryzowania badań geologicznych w okresie międzywojennym na Górnym Śląsku. Podkreślono rolę i znaczenie, pracowników Państwowego Instytutu Geologicznego, a szczególnie Stanisława Doktorowicza-Hrebnickiego i Stefana Czarnockiego, w poznaniu oraz tekstowym i kartograficznym przedstawieniu skomplikowanej budowy geologicznej tego regionu.
EN
From the perspective of about 90 years a trial of characteristics of geological investigations in the period between the two World Wars in Upper Silesia was presented. The role and significance of workers of the State Geological Institute, and especially Doktorowicz-Hrebnicki and Stefan Czarnocki, in the recognition as well as text and cartographic presentation of the complicated geological structure of this region were emphasized.
The result of palaeobotanical studies of biogenic sediments from Pakosławice made it possible to establish the age of limnic and peat sediments and reconstruct past plant communities and development phases of the sedimentary/sedentary basin. The investigated mire originated from overgrowth of a shallow lake. The lake formed probably as a result of thermokarst processes (permafrost thawing). Accumulation of gyttja started in the Alleröd to continue in the Younger Dryas and early Holocene (Preboreal and Boreal). The sedentation of peat deposits probably took place in the middle and late Holocene.
TheMizerna site (Polish Western Carpathians) is one of the most important Pliocene palaeobotanic sites in Central Europe. Its fresh-water deposits, laid down in a buried river valley, were studied in detail more than half a century ago in natural exposures and shallow boreholes, prior to partial drowning of the area by an artificial lake. The deposits yielded a very rich macrofossil plant collection elaborated in detail by Szafer (1954) who claimed that they represented a continuous succession of the Pliocene through Early Pleistocene plant communities. First palynological examination of the Mizerna deposits (by Oszast) was made more than half a century ago. Re-evaluation of stratigraphic and palaeoclimatic significance of macrofossil plant remains, along with a reassessment of palaeoenvironmental and sedimentary conditions during formation of the Mizerna fresh-water deposits, is in progress. This may help elucidate the problem whether the Mizerna sediments represent both the Pliocene and Early Pleistocene or, solely, the Pliocene successions.