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EN
The paper describes a new profile of lake-bog sediments at the Srebrna site in central Poland. Palynological analysis of deposits confirmed their Eemian Interglacial to Early Vistulian age. Based on palynological data the authors made a reconstruction of climate and vegetation changes from the middle Eemian Interglacial to the beginning of the Early Vistulian.
EN
Palynological analysis of the Tomisławice opencast mine deposits has allowed reconstruction of the plant communities and investigation of the evolution of sedimentary environments at various stages of lignite-forming marsh development, recorded in the composition of pollen assemblages from deposits of the 1st Mid-Polish lignite seam (MPLS-1). Rich pollen communities from an ~9 m thick section has enabled study of the succession of plant communities and of the evolution of phytogenic sedimentation. The pollen succession indicates that the assemblages in the whole lignite seam represent the VIII Celtipollenites verus pollen Zone. Slight differences in the composition of the communities reflect different stages of basin development, depending more on the variable water dynamics than on climatic oscillations. Lignite of the MPLS-1 developed in a continental regime on alluvial plains. Changes in the succession of plant communities in the Tomisławice section record flooding-drainage cycles caused by groundwater level oscillations. Peat bog accumulation took place in river basins, in which the lack of siliciclastic intercalations within the massive lignite seams points to weak fluvial dynamics. A rise in groundwater level and/or surface water resulted in flooding of the marshes and the formation of an extensive shallow lake basin, as shown by the presence of freshwater algae and pollen of aquatic plants. The section as a whole does not record an increased contribution of thermophilic plant taxa. The flora was generally dominated by warm-temperate and thermophilic species, without the participation of strongly thermophilic vegetation, which indicates that the lignite seam in the Tomis³awice opencast mine was formed in the generally stable conditions of a warm temperate climate.
EN
We describe the penultimate glacial – last interglacial transition from the one of the numerous palaeolake successions in central Poland, which have yielded many documented Eemian and Early Weichselian floral records. In the new profile, Parchliny 2016, the lacustrine deposits were analysed lithologically, botanically, zoologically, and geochemically, providing new data that illustrate the environmental transition from the Late Saalian (MIS 6a) to the Eemian interglacial (MIS 5e). Five phases of palaeolake development have been distinguished. The first phase was related to the rapid melting of a dead ice block buried in the tills to form a lake. The second phase documented a Late Saalian initial succession, with the dominance of open steppe communities (Stadial 1), followed by a third phase with gradual increasing density of vegetation, the spread of boreal forests (Zeifen interstadial) and further increase in open communities and the retreat of pine (Kattegat stadial). The fourth phase reflected the beginning of Eemian interglacial by the expansion of pioneering birch-pine and purely birch forests and an increasing proportion of deciduous trees, including oak (Vth phase). Diatom, cladoceran and geochemical studies indicate at least two stages of lake development. The first stage (Late Saalian) was of an open lake (2–4 m deep), in relatively cold conditions and nutrient-poor water with the lowest amounts of organic carbon and nitrogen. The second stage (Eemian interglacial), shows warmer, shallower conditions in which the lake’s primary production increased, the water was well oxygenated, and there were more trophic levels.
EN
The article presents results of research of three sections (Kuców 9, 10 and 16). Two of them record fluvial and lacustrine interglacial sediments and the third, cold-stage glaciolacustrine sediments. They were formed inside the Miocene–Pliocene syncline depressions in a central part of the southern horst within the Kleszczów Graben. Fluvial and lacustrine deposits of the Middle Pleistocene Interglacial (Mazovian or Ferdynandovian in the Czyżów Formation) are described from the Kuców 9 and 10 sections. Their sediments are located in marginal parts of a buried river valley and within an oxbow palaeolake, then covered by glaciofluvial deposits of the Ławki (Early Saalian) and Rogowiec (Late Saalian) Formations. The Kuców 16 section comprises ice-dam sandy lithofacies (Kuców Formation, Elsterian) of a marginal part in a proglacial lake. Two pollen diagrams of K65/15 and Kuców 9 sections represent the Mazovian (Holsteinian) succession, although in the Kuców 9 section some features are typical for the Ferdinandovian succession.
EN
Our high-resolution data of pollen and macrofossils from 2 cores taken from the Jagodne site (Garwolin Plain) reveals a pollen succession covering the final part of the Late Saalian (Marine Isotope Stage MIS 6) and embracing the Eemian (MIS 5e). The results correspond to Regional Pollen Assemblage Zones (RPAZ). The hornbeam phase (E5 RPAZ) has been subdivided into subzones and compared to the corresponding division of the key profile of the Garwolin Plain, Kozłów K2-19. The comparison revealed a considerable sedimentary hiatus in the E5 RPAZ at Jagodne. This is attributed to significant palaeohydrological changes occurring widely in this zone, and also seen at other Eemian sites in Poland. Another specific feature of the Jagodne site is the early, rapid terrestrialisation of the palaeolake and its transformation into a raised bog, which occurred already at the end of the hornbeam phase. The Sphagnum dominated peatbog developed for a long time as evidenced by a thick peat layer covering also the Early Vistulian. Both pollen and plant macrofossil data correspond well to observed lithological boundaries, providing a consistent record of palaeoenvironmental and palaeoclimate changes. The results obtained contribute to knowledge of palaeoenvironmental changes and palaeoclimate interpretation of that area.
EN
Interpretation of the regional high-resolution seismic data of the PolandSPANTM survey in the Grudziądz-Polik area revealed a new depositional architecture of the Upper Cretaceous succession that differs substantially from the previously assumed layer-cake model, commonly applied to Permian-Mesozoic sequences. A previously unrecognized regional unconformity, dividing the Upper Cretaceous succession into two units characterized by very different internal geometries, was identified and mapped. The lower unit, with a generally layer-cake internal pattern, is overlain by an upper unit composed of a regionally low-angle succession that pinches out toward the south. This newly revealed regional pattern remained unrecognized in previous regional compilations based on borehole data, which suggested that a layer-cake depositional architecture prevailed throughout the entire Upper Cretaceous. This new image of Upper Cretaceous depositional patterns has far-reaching consequences for understanding of the evolution of the Polish Basin in the Late Cretaceous, including its subsidence and burial history, deposition, and tectonic development. A re-evaluation of the chronostratigraphy of the Upper Cretaceous of the Polish Basin is needed to temporally constrain the succession of sedimentary and tectonic events revealed here.
EN
The paper presents the research on the increasing in the floristic diversity of abandoned Arrhenatherion elatioris meadows through the introduction of three dicotyledonous species: Achillea millefolium, Daucus carota and Leucanthemum vulgare and the re-management. They were carried out in the meadows of the landscape reserve “The Ursynów Escarpment” (“Skarpa Ursynowska”) in 2016-2018. The studies were aimed at restoring natural values of these meadows, especially their landscape and aesthetic functions. The experiment was designed in the community of Arrhenatherum elatius + Bromus inermis, as a randomised complete block, with eight replications, on the plots of 2 m2. In each plot the diaspores (collected in The Lower Pilica Valley) were sown close to the centre of the plot, within an area of 0.5×0.5 m. In the sowing year two top-cuttings and one productive one were made. In the following years the meadows were mowed once or twice. The following features were estimated: the abundance of sown species populations, the seedling density, the heights of the sown species, the height of the resident vegetation, the total ground cover, the species composition of the sward and the species richness. The improvement of the landscape and aesthetic functions of the reserve due to increasing in the species richness from 10 to 38 species and significant decreasing in Urtica dioica share was achieved. The species diversity, described with the Shannon-Wiener index, enlarged of 53% in the first year after oversowing. The introduced species decided also about the improvement of the total ground cover. Fast and lasting effect was obtained especially on the area over-sown with L. vulgare. The good effects in the first two years were obtained also in the plots with D. carota (biennial species). A. millefolium was characterised by significantly fewer number of seedlings but its population abundance was increasing gradually during the following years. The impact of high grasses (A. elatius, B. inermis) on the soil coverage by the plants of sown species and their heights was shown. The studies also proved that in the conditions of summer drought the resident vegetation may protect the seedlings against the temperature and evapotranspiration.
EN
The present study focuses on alternative methods of exploiting lignite in comparison to conventional opencast mining and combustion in power plants for the generation of electricity. In Poland, opencast lignite pits cover large areas, creating social and environmental conflicts. In order to stabilise the production level of electricity and reduce the negative effects of opencast mining, alternative ways of exploiting lignite are suggested, one of these being underground gasification in situ. The Złoczew lignite deposit, which will most likely be exploited in the near future, provides an opportunity to discuss the unconventional method of underground coal gasification (UCG). On the basis of technological and geological criteria that have been established to determine the suitability of Polish lignite for underground gasification, resources to be used this way have been estimated. Through gasification, over 15 million tonnes of lignite can be utilised, which is about 2.5 per cent of resources of the Złoczew deposit intended for opencast mining. With this in mind, we suggest to take action by starting a pilot installation, to be followed by a commercial one for underground gasification after completion of superficial mining. Naturally, any future application of this method will be preceded by assessment of geological conditions at the Złoczew opencast pit.
10
Content available remote A Tree-Ring chronology from Allerød–YD transition from Koźmin (Central Poland)
EN
Subfossil trunks of pine (Pinus sylvestris L.) from the Late Weichselian were discovered in the site Koźmin in the Koło Basin, central Poland (Dzieduszyńska et al., 2014a). Another part of organic sediments with trunks was excavated in the frame of the research project. Altogether 224 samples from Koźmin were analysed dendrochronologically; they represented generally young trees, 40 to 70 years old. Based on the most convergent sequences, the chronology 2KOL_A1 was produced, 210 years in length. With the wiggle-matching method, it was dated to ca. 13065–12855 cal BP. Dendrochronological dating of trunks buried in organic sediments, most of which occurred in situ, revealed that tree deaths occurred successively, over more than 100 years. That could have been due to unfavourable climatic conditions, as well as extreme events, e.g. strong winds.
EN
New magnetostratigraphic data from the Middle Buntsandstein section, drilled in the Brześć Kujawski IG-1 borehole (Central Poland), are presented and discussed. The chronostratigraphic positions of particular formations of the Buntsandstein are discussed as well. The magnetic polarity pattern obtained from the Brześć Kujawski IG-1 borehole matches the pattern obtained earlier in other boreholes from the Polish part of the Central European Basin. Although magnetostratigraphy and palynological evidence undoubtedly indicates that the Induan/Olenekian boundary in the Polish part of the CEB is located in the lower part of the Pomerania Formation, the placement of the Olenekian/Anisian boundary within the sedimentary sequences of the Central European Basin remains problematic. This boundary most probably is located within the upper part of the Upper Buntsandstein, as can be inferred from palynological studies.
EN
GPR method is perfectly suited for recognizing of sedimentary facies diversity in shallowly occurring sediments if there is a contrast of electrical properties between and/or within each layer. The article deals with the issue of the correlation between GPR surveys results and sedimentological analyses. As a result of this correlation a conceptual model of depositional systems of studied areas was developed. Studies were performed in two areas located in central Poland, where glacial deposits formed in the Middle Polish (Saalian) Glaciation are present. The study was based on 49 sediment samples and 21 GPR profiles. Analyses of litho facies as well as granulometric and mineralogical composition of deposits of collected samples were carried out, showing the diversity of glacial deposits in both study sites. During GPR measurements shielded antenna with a frequency of 500 MHz was used which allowed high-resolution mapping of the internal structure of deposits and to identify four characteristic radar facies. Correlation of GPR profiles with point, one-dimensional sedimentological studies allowed the unambiguous interpretation of the GPR image and draw conclusions about the formation environment of individual units. Geophysical and sedimentological data obtained during study provide a new and detailed insight into selected glacial deposits in central Poland.
PL
Podczas prac kartograficznych prowadzonych w celu realizacji arkusza Nowe Miasto nad Pilicą Szczegółowej Mapy Geologicznej Polski (SMGP) 1:50 000 wykonano następujące otwory badawcze: Wólka Ligęzowska, Wysokin, Sacin, Ceteń 8 i Ceteń 9. Osady występujące w profilach Wysokin, Sacin, Ceteń 8 i Ceteń 9 reprezentowały formację preglacjalną z charakterystycznymi warstwami piaszczystymi, mułkowymi, piaszczysto-mułkowymi i ilastymi, często z humusem i przewarstwieniami torfu. Seria z Wólki Ligęzowskiej miała charakter jeziorno-bagienny. W celu rekonstrukcji zmian roślinności i klimatu posłużono się metodą analizy pyłkowej. Historię zmian roślinności odniesiono do wydzielonych poziomów pyłkowych, które pogrupowano w fazy rozwoju roślinności, a następnie okresy klimatyczno-stratygraficzne. Podstawę do wydzielenia tych faz i okresów stanowiły: podobieństwo florystyczne lokalnych zespołów poziomów pyłkowych (L PAZ), występowanie elementów flory subtropikalnej (P2), arktycznotrzeciorzędowej (A), procentowy udział poszczególnych taksonów w poziomach pyłkowych, procentowy udział taksonów ciepłoumiarkowanych (A1) i chłodnoumiarkowanych (A2), należących do geoflory arktycznotrzeciorzędowej (A). Ponadto wzięto pod uwagę stosunek wartości pyłku drzew i krzewów (AP) do pyłku krzewinek i roślin zielnych (NAP) jako wskaźnik odlesienia i otwartości krajobrazu, skład taksonomiczny oraz procentowy udział NAP, wskazujący na charakter zbiorowisk występujących na siedliskach otwartych. Okresy klimatyczno-stratygraficzne stanowią podstawę do podziału stratygraficznego badanych osadów i jednocześnie dokumentują wielkoskalowe zmiany klimatyczne, wyrażające globalne zmiany klimatu. Interpretacja danych palinologicznych pozwala na określenie wieku osadów z Wólki Ligęzowskiej. Dane pyłkowe pozwalają na korelację fazy 1 WL z poziomem XIII Sequoiapollenites i odniesienie do piętra zankl. Następne fazy, 2 i 3 WL, odniesiono do poziomu XIV Faguspollenites. W związku z brakiem poziomu pyłkowego dla fazy 4 WL zaproponowano wydzielenie poziomu XV Pinuspollenites. Okres II skorelowano z piętrem piacenz. Zapis silnego ochłodzenia klimatu, jaki występował między II i III okresem klimatyczno-stratygraficznym w Wólce Ligęzowskiej, można korelować z globalnymi zmianami klimatycznymi występującymi na granicy neogen/ czwartorzęd, które są datowane astronomicznie na 2,588 Ma, a strop osadów okresu II należy korelować z morskim stadium izotopowym MIS 103. Sekwencja zmian roślinności i klimatu z Wólki Ligęzowskiej doskonale koreluje się z globalnymi zmianami klimatycznymi charakterystycznymi dla pliocenu (do 2,6 Ma) i plejstocenu dolnego. W profilach z Wysokina, Sacina, Cetenia 8 udokumentowano głównie zapis palinologiczny schyłku okresów ciepłych i okresy zimne zgodne z cyklem zmian klimatycznych w plejstocenie dolnym, w którym występują oziębienia i ocieplenia klimatu związane z rozwojem i zanikiem pokrywy lodowcowej na półkuli północnej. Facje rzeczne, z których w większości jest zbudowana formacja preglacjalna, powodują występowanie luk w zapisie palinologicznym, a stopień rozpoznania zmian roślinności w tym czasie jest bardzo ogólny. W miarę konsekwentny przebieg zmian roślinności i klimatu pozwala na wyróżnienie w obrębie plejstocenu dolnego nowej jednostki klimatyczno-stratygraficznej – ocieplenia ceteń. Na podstawie wyników analizy pyłkowej wiek osadów skorelowano z innymi stanowiskami z Polski i Europy.
EN
Mapping survey carried out within the Detailed Geological Map of Poland, 1:50,000, sheet Nowe Miasto nad Pilicą, included drillings at the following locations: Wólka Ligęzowska, Wysokin, Sacin, Ceteń 8 and Ceteń 9. Sediments of Wysokin, Sacin and Ceteń 8 and 9 represented a preglacial series with characteristic sandy, silty, sandy-silty and clayey layers, frequently with humus and interbeddings of peat. The series from Wólka Ligęzowska was of a lacustrine-boggy type. Changes in vegetation and climate were reconstructed by means of pollen analysis. The history of vegetational changes was referred to the distinguished Local Pollen Assemblage Zones, grouped into phases of vegetational development and, eventually, into climatostratigraphic periods. Climatostratigraphic periods provided a basis for the distinction of stratigraphic units within the examined sediments and served as a record of large-scale climatic changes resulting from global climate changes. The phases and periods were defined on the basis of: floral similarity of L PAZ, occurrence of subtropical (P2) and arctic-Tertiary (A) elements and their frequency, percentage values of particular taxa in zones, percentage values of warm-moderate (A1) and cool-moderate (A2) taxa of the arctic-Tertiary (A) geoflora, AP/NAP ratio (pollen of trees and shrubs/ pollen of dwarf shrubs and herbaceous plants) as an indicator of deforestation and landscape openness, percentage values and taxonomic composition of NAP. Interpretation of the obtained palynological data provided a basis for determining the age of sediments from Wólka Ligęzowska. Pollen data support a correlation of phase 1 WL with zone XIII Sequoiapollenites (Piwocki, Ziembińska-Tworzydło, 1995, 1997) and with the Zanclean. The subsequent phases, 2 and 3 WL, are conformable with zone XIV Faguspollenites. As phase 4 WL could not be assigned to any zone, distinction of zone XV Pinuspollenites was proposed. Phase II was correlated with the Piacenz. The strong climatic cooling, recorded in Wólka Ligęzowska between climatostratigraphic periods II and III, is likely to correspond to global climatic changes typifying the Neogene/ Quaternary boundary, astronomically dated to 2.588 Ma, while the top part of period II sediments should be correlated with MIS (Marine Isotope Stage) 103. The sequence of vegetational and climatic changes from Wólka Ligęzowska shows an excellent correlation with global climatic changes typifying the Pliocene (up to ca. 2.6 My) and Lower Pleistocene. The sections of Wysokin, Sacin and Ceteń 8 bear mainly a palynological record of the closing phases of warm and cold periods, conformable with the Lower Pleistocene cycle of climatic changes, following the de¬velopment and disappearance of glacial cover in the Northern Hemisphere. Regrettably, the most of the preglacial series are formed by fluvial facies: the palynological record includes gaps, allowing only for a partial reconstruction of the vegetational changes proceeding in this time. Within the Lower Pleistocene, the climatostratigraphic unit of the Ceteń warming was defined. Results of pollen analysis provided a basis for correlating the age of sediments with other Polish and European sites.
EN
The petrographical features of the medium- and coarse-grained gravels (4-10 mm and 20-60 mm, respectively) of weathered and fresh (unweathered) deposits indicate, in combination with so-called indicator and statistical erratics, that two glacial lobes joined in the borderland of the Polish Lowlands and Uplands. Lower Palaeozoic limestones become less frequent in the finer gravel fraction, whereas crystalline rocks and flints become more frequent. The petrographical analysis of the coarser gravel fraction indicates that the ice sheet advanced from the NE to NNW (the Widawka lobe) and from the NE to ENE (the Rawka, Pilica and Luciąża lobes). The source areas of the gravel deposited by the Warthian ice sheet were magmatic and sedimentary areas of both the Baltic and the SE Sweden basins.
EN
The heavy-mineral assemblages of Pleniglacial fluvial sediments were analysed for two river valleys, viz. the Luciąża River (at Kłudzice Nowe) and the Belnianka River (at Słopiec). These sites, on the Piotrków Plateau and in the Holy Cross Mountains respectively, are located in different morphogenetic zones of Poland that were affected to different degrees by the Middle Polish ice sheets. The study was aimed at determining the kind of processes that modified the heavy-mineral assemblages in the two fluvial sediments, at reconstructing the conditions under which these processes took place, and in how far these processes caused changes in the assemblages. The heavy-mineral associations of the parent material was taken as a starting point; this parent material were the sediments left by the Odranian glaciation (Warta stadial = Late Saalian). It was found that heavy-mineral assemblages in the Luciąża valley deposits are varied, particularly if compared with other fluvioglacial Quaternary deposits from the Polish lowlands, with a dominance of garnet. In the fluvial deposits of the Belnianka valley, zircon, staurolite and tourmaline dominate, with minor amounts of amphibole, pyroxene, biotite and garnet. This suggests that the deposits were subject to intensive and/or persistent chemical weathering and underwent several sedimentation/erosion cycles under periglacial conditions. In both valleys chemical weathering and aeolian processes were the main factors that modified the assemblages of the transparent heavy minerals; these processes were largely controlled by the climatic changes during the Pleistocene.
EN
The 1st Middle-Polish (1st Lusatian) Lignite Seam is exploited in open-cast mines in central Poland. A large number of lignite lithotypes, grouped in four lithotype associations, are distinguished: xylitic, detritic, xylo-detritic and detro-xylitic lithotype associations, which show various structures. Each lithotype association was produced under specific peat-forming environmental conditions. In the case of the lignite seams under study they represent all the main environments that are known from Neogene mires, i.e.: fen or open water, bush moor, wet forest swamp and dry forest swamp. For a simple and practical description in the field of both the lignite sections and borehole cores, a new codification for lignite lithotypes is proposed. It is based on the codification of clastic deposits (lithofacies). The practical value of the new lignite lithotype codification is examined in three vertical sections of the 1st Middle-Polish Lignite Seam.
EN
Palaeoslopes of Weichselian sand-bed braided rivers have been reconstructed for two stages of fluvial development in the Toruń Basin. (1) The palaeoslope of the ‘fossil’ fluvial succession (buried under Weichselian tills) was calculated on the basis of the median grain size and the Shields parameter. The hydraulic gradient thus found is comparable with the hydraulic gradient of the present-day river. (2) The second developmental stage of the Toruń Basin (as a apart of the Noteć-Warta ice-marginal valley) took place after deglaciation. The slopes of river terraces are a few times lower than those calculated on the basis of the Shields parameter. The palaeoslope of the then river was estimated on the basis of a constant interdependency between the braidplain width, the channel geometry and the grain size. The river gradient that was thus calculated is similar to the measured terrace slope. Palaeoslope estimates in valleys similar to those in the Toruń Basin should consider the width of the braidplain.
EN
Eighteen samples of Quaternary unconsolidated sediments from the Piotrków Plateau and the Radomsko Hills in central Poland have been analysed for their average grain size, sorting, skewness and kurtosis. The analysis was carried out by seven computational methods of interpolation and nine extrapolation methods. It appears that linear interpolation, the traditional method (DOS), and the Josek and Gradistat Programs give comparable results, but that quadratic interpolation and the method of moments should not be applied since they yield unreliable results. The method of moments gives unduly high or unduly low parameter values because of the application of different, i.e. incomparable measures in the applied formulae. It should be stressed that only extrapolation provides, if performed under the right conditions, the possibility to determine some parameters, in particular skewness values.
PL
Struktury glacitektoniczne znane dotychczas z rejonu Kotliny Płockiej rejestrowano w osadach środkowo- i dolnoplejstoceńskich oraz neogeńskich, a ich powstanie wiązano z erozją lądolodów starszych od zlodowacenia Wisły. W odsłonięciach w Kretkach i Zawadzie Nowej, znajdujących się w południowej krawędzi Kotliny Płockiej, stwierdzono deformacje glacitektoniczne związane z nasunięciem lądolodu stadiału głównego zlodowacenia Wisły. Struktury glacitektoniczne nie mają odzwierciedlenia we współczesnej rzeźbie, natomiast ich występowanie jest ściśle powiązane z przebiegiem kopalnego skłonu wysoczyzny z okresu zlodowaceń środkowopolskich. Zasięg wgłębny zaburzeń jest ograniczony i wynosi od 2 do 6 m. W Kretkach i Zawadzie Nowej przeprowadzono analizę strukturalną zaburzeń oraz badania litofacjalne osadów. Rozpoznane deformacje to zarówno proglacjalne struktury glacitektoniczne powstałe przed czołem lądolodu w wyniku kompresji, a wyrażone jako fałdy i nasunięcia, jak i subglacjalne deformacje glacitektoniczne, utworzone pod poruszającym się lądolodem, wykształcone jako struktury wleczeniowe i laminacja tektoniczna w subglacjalnej warstwie deformacyjnej. Dokonano rekonstrukcji kierunku lokalnego transportu glacitektonicznego, działającego w azymucie 334–352° i skierowanego z NNW ku SSE, a także określono ogólne cechy lobu płockiego, wskazując na małą miąższość, szybki ruch oraz ciepły reżim bazalny lądolodu.
XX
Glaciotectonic structures well known from the Płock Basin area were identified within the Lower and Middle Pleistoceneand Neogene sediments, and their formation was connected with erosion of the ice-sheets older than the Vistulian Glaciation. Actually, at the Kretki and Zawada Nowa exposures, situated in the southern margin of the Płock Basin, glaciotectonic deformations of the Main Stadial of the Vistulian (= Weichselian) Glaciation ice-sheet have been recognized. The structures are not reflected in topography but their spatial distribution is strictly connected with the existence of the buried slope of the Middle Polish Glaciation morainic plateau. In-depth extent of young glaciotectonic deformations is limited and ranges from 2 to 6 m. Sedimentological investigations, and particularly lithofacies analysis, along with structural examinations of deformation structures have been carried out at Kretki and Zawada Nowa. Recognised glaciotectonic deformations are both proglacial compressive structures, expressed as folds and over thrusts, and subglacial glaciotectonic structures, formed beneath the moving ice, and featured as drag structures and tectonic laminations in the subglacial deforming bed. A local direction of glaciotectonic transport has been reconstructed as acting from NNW to SSE (334-352° azimuth), and general parameters of the Płock lobe have been evaluated indicating a small thickness, fast ice flow and warm basal regime of the ice-sheet.
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