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EN
Brown coal and overlying sand strata from the Łukowa-4 borehole, located in the northeastern sector of the Carpathian Foredeep in Poland, were studied for palynology. These strata are underlain by Upper Eocene sands, and covered by Middle Miocene rocks. Coal beds yielded infrequent sporomorphs and freshwater algae Botryococcus. The presence of the latter indicates that these deposits accumulated in a freshwater environment whereas sporomorph assemblages point to the presence of mixed forests with a significant portion of thermophilous taxa. Age of the coal beds has been established based both on the presence of species that appear for the last time in the Early Oligocene, and on the similarity with sporomorph spectra from the Lower Oligocene of the Polish Lowlands. Overlying sands yielded marine dinoflagellate cysts, which point to a marine sedimentary setting, and frequent sporomorphs. The latter indicate the presence of mixed mesophytic forests, bush swamps, swamp forests, and riparian forests in the vicinity of lacustrine environments. Stratigraphic analysis of dinoflagellate cyst and sporomorph assemblages suggests that the sands accumulated in early stages of Miocene transgression in the Carpathian Foredeep in the latest Early–early Middle Miocene. Our climatic interpretation of the sporomorph spectra suggests that the climate during deposition of the strata was relatively warm, although less frequent thermophilous taxa recorded in the Miocene sands suggest a slightly cooler climate than that deducted from the spectra yielded by the underlying Lower Oligocene coal beds. Correlation of Lower Oligocene coal beds with neighbouring coeval marine sands suggests diverse morphological conditions in the Carpathian foreland at that time, partly covered by a sea, and partly emerged. A similar, morphologically diverse basement in the Carpathian foreland favoured accumulation of Lower Miocene phytogenic deposits. A similar stratigraphic position of both Lower Oligocene and Lower Miocene coal beds in the Carpathian Foredeep may result in a false correlation of these strata devoid of fossils, which are commonly regarded as Miocene.
EN
Latest Eocene plant macrofossils and trace fossils collected a century ago by Wiktor Kuźniar are revised and their stratigraphical and palaeoecological meaning is re-considered. They derive from marine limestones and marls cropping out on the northern slope of the Hruby Regiel mountain in the Western Tatra Mountains. Leaves belonging to the families Fagaceae and Lauraceae and fruits of the palm Nypa are recognized. The co-occurrence of the planktonic foraminifer taxa Chiloguembelina cf. gracillima and Globigerinatheca cf. index and fruits of Nypa suggests a latest Eocene age of the fossil flora. The plant assemblage is typical of paratropical or subtropical evergreen forests in a warm and humid subtropical climate, recent counterparts of which occur in southeast Asia. The presence of Nypa is characteristic of mangroves. The good state of preservation of the leaves suggests coastline proximity during sedimentation of the plant-bearing deposits.
EN
The Zoloushka Cave belongs to a group of the largest gypsum caves in Western Ukraine (Bukovina region), developed in the middle Miocene (upper Badenian) evaporite series (Tyras Formation) on the SW periphery of the East European Platform. It is developed in the lower part of the evaporite series composed of gypsum, which is covered by a carbonate layer (Ratyn Limestone). The uneven upper surface of the gypsum at the contact with the limestone, the frequent occurrence of palaeokarst forms, and the presence of karstified fissures filled with allochthonous material indicate a sedimentation break between the gypsum and the overlying limestone. To support this thesis and to add new data on the age and palaeoenvironmental conditions of palaeokarst formation in the Bukovina region, palynological studies were carried out on material from the Zoloushka Cave. Palynofacies, sporomorphs and dinoflagellate cysts were studied. In total, over 70 sporomorph taxa and over 25 dinoflagellate cyst taxa have been identified in four samples collected from the filling of the palaeokarstic forms in the cave. The results of the analysis of sporomorphs and dinoflagellate cysts point to the formation of the palaeokarst during the sedimentation break that took place at the end of the late Badenian evaporitic cycle in the Western Ukraine region. The subsequent marine transgression led to the filling of the karst forms in gypsum with chemogenic carbonate material, precipitated from marine water (draperies) and with fine-grained, clastic material (pockets and fissures).
EN
This paper describes sedimentology and palynology of freshwater plant-bearing late Cenozoic (Pliocene sensu lato) deposits drilled at Mizerna, the eastern part of the Nowy Targ Intramontane Depression, West Carpathians, South Poland. Our data were obtained from a newly-analysed 39-m thick succession from the Mizerna-Nowa borehole, containing spores, pollen and freshwater organic-walled algal micro-remains. They shed light on the palaeoenvironmental conditions of the Nowy Targ Intramontane Depression, where the Mizerna palaeolake once formed.
EN
A new palaeopalynological investigation was conducted on 15 samples from four test-pits at the Gray Fossil Site (Bear Pit, Elephant Pit, Test Pit 2-2010, and Rhino Pit). In total, 50 morpho-species of miospores (including five species of spores, eight species of gymnosperm pollen, and 37 species of an giosperm pollen) and 18 morpho-species of fresh water algal micro-remains were identified. One new morphological species, related to zygospores of the Zygnemataceae, Stigmozygodites grayensis sp. nov., is proposed. The assemblage of fossil algae recovered provides in sights into the palaeoenvironmental conditions of the uppermost (125 cm) part of the Gray Fossil Site sedimentary cover, deposited after the formation of a number of sink holes, and the fill of the palaeosinkholes. Most of the algae identified prefer meso- to eutrophic conditions and are characteristic of stagnant to slowly flowing shallow fresh water. Therefore, the lacustrine fossiliferous sediments at the Gray Fossil Site represent pond deposits. The palaeopalynological analysis revealed differences in the composition of the miospore and algal assemblages of the pits studied, suggesting that the Test Pit 2-2010, Bear, and Elephant pits are similar and may have been formed in the same pond, while the presence of a higher percentage of algae in the Rhino Pit may indicate sedimentation in a separate waterbody.
EN
A sinkhole, developed in Middle Triassic limestones and filled with clastic and organic deposits, including lignite, was studied, in terms of its origin and age. The sinkhole represents a solution sinkhole, which originated through the subsidence of surficial deposits into an underlying cave system. The study permitted the recognition of three main stages of sinkhole evolution. During the initial stage, subterranean and surface karstification proceeded concurrently. As a result, a terra rossa cover developed at the surface and a cavern system was formed in the underlying bedrocks. During the second phase, both systems became connected and the soil cover subsided. This, in turn, involved the formation of a depression at the land surface and ponding of the drainage water. The pond was filled with plant debris, later giving rise to lignite formation. During the third and final stage, the sinkhole was filled with quartz sands with kaolinite, derived from eroded, Upper Cretaceous sandstones and marls. Results of pollen analysis from the sinkhole indicate the presence of mesophytic forests and show a significant role of riparian forests and herbaceous vegetation. The occurrence of abundant, freshwater algae and the pollen of aquatic plants evidences sedimentation of the infill in a water body (pond). The apparent dominance of arctotertiary and cosmopolitan, palaeofloristical elements, as well as the occurrence of only sparse, palaeotropical elements (mainly subtropical), indicate a warm-temperate climate (cooler than during the Early and Middle Miocene period). A comparison of the sporomorph association from the sinkhole with those from other Neogene sites provides evidence of its Late Miocene age (Late Pannonian–Early Pontian).
EN
Pollen analysis of 16 samples of coaly sediments taken from one of sinkholes developed within the Triassic limestones cropping out at Tarnów Opolski, Upper Silesian Upland has been done. The study revealed a taxonomically rich assemblage of excellently preserved sporomorphs (pollen grains and spores) as well as microfossils of fresh-water algae (mainly Chlorophyta). The pollen analysis made it possible to reconstruct a vegetation growing during sedimentation of deposits filling the studied sinkhole and clear facies succession, from open aquatic (with abundant fresh-water algae) to marshy one (e.g. swamp forests composed of Taxodium, Nyssa and Alnus). Riparian forests dominated by deciduous trees, e.g. Pterocarya, Carya and Liquidambar, grew on wet terrains surrounding the water body. Drier elevated terrains were overgrown by mixed mesophytic forests with small admixture of thermophilous plants. Results of the pollen analysis indicate that during the sedimentation of the sinkhole filling the climate was warm temperate and moderately wet. Recorded sporomorphs and a mutual ratio of arctotertiary and palaeotropical taxa point at a Middle Miocene age of the studied deposit.
EN
Pollen grains, spores and phytoplankton from the Neogene succession of a borehole at Józefina (northern part of the Kraków–Silesia Upland, Poland) have been studied. The composition of the pollen spectra and the mutual ratio of palaeotropical and arctotertiary elementssuggest a Late Miocene age. Among the pollen grains, there are significant elements characteristic of riparian forests (Pterocarya, Caryaand Liquidambar) and mixed mesophytic forests (Pinus, Fagus and Carpinus). Such a pollen and spore association suggests a temperateand mid-wet climate, cooler than during the Early and Mid Miocene period, but still warmer than the present-day climate of Poland. Thismakes the pollen-spore association from Józefina comparable with XII climatic phase represented by the Carpinipites-Juglandaceaespore-pollen zone. The occurrence of aquatic plants and freshwater algae (e.g., Sigmopollis, Zygnemataceae and desmids) indicates alacustrine palaeoenvironment.
EN
The Zygnemataceae are an extant family of freshwater filamentous green algae which produce acid-resistant zygospores. Palynomorphs of probable zygnematacean affinity occur in sediments of the Carboniferous to Holocene age (van Geel & Grenfell, 1996). These algae reproduce using four types of spores, but only zygospores and probably aplanospores are acid-resistant and can be preserved in the fossil record. The majority of recent species have zygospores of constant form of three types: elliptical (occurring in genera Debarya and Spirogyra), square (occurring in Mougeotia) or circular (occurring in Zygnema). The zygospores normally have a three-layered wall (exospore, mesospore and endospore), but only mesospore contains a decay and acid-resistant substance (most probably algaenans), so usually only this layer is preserved in fossil state, and is of interest to palynologists. The mesospore layer is smooth or ornamented with various sculptures (Kadłubowska, 1972; Grenfell, 1995). The shape and sculpture are very important features for determination of both the recent and fossil species. Two samples from the Bełchatów Lignite Mine were palynologically examined and two types of probable fossil zygnematacean zygospores, differing in shape, were encountered. The following species have been distinguished: Tetraporina sp., Spintetrapidites quadriformis Krutzsch & Pacltová as well as Ovoidites elongatus (Hunger) Krutzsch, and O. ligneolus Potonié ex Krutzsch. The fossil genus Tetraporina is usually related to the recent zygnematacean algae zygospores of Mougeotia genus, fossil Ovoidites is the nearest the recent zygospores of Spirogyra and Sirogonium, while Spintetrapidites is similar to both zygospores of Zygnemataceae and Tetraedron green algae. Species of recent genera Mougeotia and Spirogyra are usually found in shallow, freshwater, oxygen-rich environments such as ponds, lake margins (paludal or low gradient fluvial), ditches and very slowly moving streams (Kadłubowska, 1972). Occurrence of Tetraporina and Ovoidites zygnematacean zygospores in the material studied from Bełchatów points out at presence of water basin(s) during sedimentation time. That confirms the previous geological results that formation of examined sediments took place in the environment of a meandering river (including ox-bow lakes).
EN
Marine dinoflagellate cysts are described from the basal part of the Mużaków series in the Legnica-33/56 borehole (Fore-Sudetic Monocline, south-western Poland). Their occurrence reflects marine ingression that covered this area during the Middle Miocene. Qualitative composition of dinocyst and sporomorph assemblages allows reconstructing the palaeoenvironment of present-day Legnica vicinity as a shallow marine bay with rich vegetation of the Everglades-type.
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