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EN
The present article focuses predominantly on sandy deposits that occur within the Middle Miocene lignite seam at the Tomisławice opencast mine, owned by the Konin Lignite Mine. As a result of mining activity, these siliciclastics were available for direct observation in 2015–2016. They are situated between two lignite benches over a distance of ~500 m in the lower part and ~200 m in the higher part of the exploitation levels. The maximum thickness of these sandy sediments, of a lenticular structure in a S–N cross section, is up to 1.8 m. With the exception of a thin lignite intercalation, these siliciclastics comprise mainly by fine-grained and well-sorted sands, and only their basal and top layers are enriched with silt particles and organic matter. Based on a detailed analysis of the sediments studied (i.e., their architecture and textural-structural features), I present a discussion of their genesis and then propose a model of their formation. These siliciclastics most likely formed during at least two flood events in the overbank area of a Middle Miocene meandering or anastomosing river. Following breaching of the natural river levee, the sandy particles (derived mainly from the main river channel and levees) were deposited on the mire (backswamp) surface in the form of crevasse splays. After each flooding event, vegetation developed on the top of these siliciclastics; hence, two crevasse-splay bodies (here referred to as the older and younger) came into existence. As a result, the first Mid-Polish lignite seam at the Tomisławice opencast mine is currently divided in two by relatively thick siliciclastics, which prevents a significant portion of this seam from being used for industrial purposes.
EN
The entrenched Odra palaeovalley, cut into the bedrock of the distal margin (forebulge basal unconformity) of the Moravian Carpathian Foredeep (peripheral foreland basin) is filled with an almost 300 m thick pile of Miocene deposits. The directon of the valley (NW-SE to NNW-SSE) has been controlled by faults subparallel with the system of “sudetic faults“. The sedimentary succession consists of 5 facies associations/depositional environments, which are interpreted (from bottom to top, i.e. from the oldest to the youngest) as: 1 - colluvial deposits to deposits of alluvial fan, 2 - deposits of alluvial fan, 3 - fan-delta deposits, 4 - shallow water delta to nearshore deposits and 5 - open marine deposits. This fining-up and deepening-up succession reveals the following: the formation of the new flexural shape of the basin; deep erosion connected with uplift and tilting of the forebulge and reactivation of the NW-SE trending basement faults; the Early/Middle Miocene sea level fall; alluvial deposition mostly driven by tectonics and morphology; forebulge flexural retreat; Middle-Miocene sea level rise; back-stepping of valley infill; marine invasion during the Early Badenian with shift of the coastline further landward of the pallaeovalley. Tectonics related to contemporary thrusting processes in the Western Carpathians are assumed to be the dominating factor of the studied deposition at the expense of eustatic sea level changes. Provenance studies have proven that the pre-Neogene basement (i.e. the Early Carboniferous clastic “Culmian facies” ofthe Moravian-Silesian Paleozoic) represents an important source for the conglomerates and sands, which volumetrically dominate in the palaeovalley infill. However, they also showed, that the deposits of the earlier Carpathian Foredeep Basin sedimentary stage (Karpatian in age?) covered the area under study and were eroded and resedimented into the palaeovalley infill.
3
Content available Skutki zmian klimatu na środowisko jaskiniowe
PL
W artykule przedstawiono skutki zmian klimatu na środowisko jaskiniowe (ekosystem podziemny) od momentu tworzenia się jaskiń (neogen), przez okres zlodowaceń na obszarze Polski do dnia dzisiejszego. Opracowano je na przykładzie analizy osadów Jaskini na Biśniku (położona w środkowej części Wyżyny Krakowsko-Wieluńskiej), które składają się z kilkunastu warstw zbudowanych z różnorodnych materiałów (geologicznych, paleozoologicznych, paleobotanicznych i archeologicznych) i dostarczają wiedzy na temat przeobrażeń klimatycznych. Dzięki wyróżnionym składnikom (opracowanym przez interdyscyplinarnych badaczy) i przy pomocy wyników datowania warstw osadów metodami fizykochemicznymi, dokonano rekonstrukcji poszczególnych elementów środowiskowych w jaskini (skały krasowiejącej, morfologii, mikroklimatu, wód jaskiniowych, fauny, flory oraz człowieka) w czasie geologicznym, pomiędzy którymi zachodziły określone relacje/ zależności. Wyróżnione elementy tworzyły różne układy (modele) ekologiczne na trzech etapach rozwoju jaskini (abiotycznym, biotycznym i antropicznym), które wydzielono w następstwie zmian klimatycznych.
EN
The article presents the effects of climate change of the cave environment (underground ecosystem) since the formation of caves (Neogene Period), through the glaciation period in Poland to the present day. They were developed on the example of the analysis of the Biśnik Cave sediments (located in the central part of the Cracow-Wieluń Upland), which consist of several layers made of various materials (geological, paleozoological, paleobotanical and archaeological) and provide knowledge about climate change. Thanks to the distinguished components (developed by interdisciplinary researchers) and using the results of dating of sediment layers using physicochemical methods, reconstruction of individual environmental elements in the cave (karstifited rock, morphology, microclimate, cave waters, fauna, vegetation and man) was made during the geological period between which occurred specific relationships / dependencies. The distinguished elements formed various ecological systems (models) at three stages of cave development (abiotic, biotic and anthropic), which developed as a result of climate change.
EN
Miocene deposits in the eastern portion of the Greater Ughelli, Central Swamp and Coastal Swamp depobelts contain well-developed brackish-water trace fossil assemblages. Twelve ichnogenera have been identified, namely: Asterosoma, Bergaueria, Chondrites, Gyrolithes, Thalassinoides, Lockeia, Palaeophycus, ?Conichnus, Planolites, Siphonichnus, Skolithos and Diplocraterion. In addition, common non-descript, passively filled burrows and fugichnia (escape structures) have also been observed. The above-mentioned ichnogenera and associated non-descript structures can be arranged into six distinct and recurring ichnoassociations within the Greater Ughelli, Central Swamp and Coastal Swamp depobelts. Each ichnoassociation is comprised of a group of trace fossils which collectively reflect specific environmental conditions during deposition of these Miocene strata. All trace fossil assemblages illustrate deposition in nearshore, restricted settings. Ichnological and sedimentological criteria which may be utilized to recognise brackish-water deposits are discussed and illustrated in pictures of the cores studied.
EN
The Hoanh Bo Basin has developed over multiple periods since the Miocene period in association with the tectonic activity of the Chi Linh-Hon Gai and Trung Luong Faults. The basin is filled with Neogene continental sediments, comprising mainly polymictic conglomerates, sandstones, siltstones, claystones, and shales. Coarser-grained polymictic deposits predominate along the northern and western margins of the basin, whereas different types of siltstones, claystones, and sandstones occur in its centre, as well as along its southern and eastern parts, toward the Ha Long Bay. The conglomerates and sandstones are composed mainly of quartz and sedimentary rock fragments, and a small amount of mica. Cement is mainly built of iron-oxide, clay or carbonate mud. The source area for the Hoanh Bo Basin sediments was located in the close vicinity of the basin. It was built of strongly weathered rocks of the Hon Gai, Ha Coi, Cat Ba Formations.
EN
Pollen analysis has revealed the presence of the edmundi morphotype in the Paleogene and Neogene sediments of Central Europe. Its species, characterized by different morphologies, are mainly assigned to two families of extant plants – the Araliaceae and the Mastixiaceae – and compared to pollen of some genera (Diplopanax and Mastixia from the Mastixiaceae, and Aralia, Fatsia and Schefflera from the Araliaceae). The most significant genus for palaeoclimate reconstructions is the extant Diplopanax, whose seeds, similarly as the seeds of other representatives of the Mastixiaceae, appear in the warm phases of the Neogene. The type species of Edmundipollis (E. edmundi) has been compared to Diplopanax pollen. Based on similarities with extant plants, the CA (Coexistence Approach) was determined. The results indicate a very warm and humid subtropical climate (Cfa–Cwa) according to the Köppen classification.
EN
The possible existence of a circular structure in the Kościerzyna region (northern Poland) was suggested in two papers in the 1980s. The current studies were aimed at verifying this hypothesis. Analysis of a digital terrain model of the pre-Quaternary surface relief as well as of the present terrain revealed the existence of a large structure of ca. 50 km in diameter. Its geometry was established based on a model of the Neogene/Pliocene surface and identifiable lineaments. Its characteristic feature is the presence of rim-like forms, an internal plateau, and a “high” in the centre. The structure is estimated to date from before the Pleistocene. The circular structure has been reshaped by glacial erosion and accumulation, and is now buried under Quaternary deposits. The existence of the Kościerzyna circular structure was confirmed by conducted studies, but my hypothesis of an impact origin is still uncertain and needs to be confirmed by future research.
8
Content available remote Paleogen i neogen : czas dynamicznych zmian klimatycznych
EN
The paper discusses the causes of climate change in the latest Cretaceous and the Paleogene (impact event or huge volcanic eruptions?). The climatic evolution (global and – more specifically – in the territory of Poland) during the Paleogene and Neogene in relation to the major climatic events of these periods (PETM, EECO, C4 grassland, Messinian Salinity Crisis) are described and their causes are discussed. Tectonic transformation, volcanic events and earthquakes led to the change in the position of the continents and in the circulation of ocean currents, as well as to increased emission of greenhouse gases – methane and carbon dioxide. These were the main causes of climate changes during the Paleogene and Neogene.
EN
The anisotropy of magnetic susceptibility (AMS) of sedimentary rocks has been used for interpreting wide range of processes: early rock deformations, palaeotransport directions, as well as the evolution of mineral content. Various sedimentary factors which may determine magnetic susceptibility within lacustrine, river, floodplain and swamp deposits have been examined in the Oravica section of the Orava-Nowy Targ Basin. Multiple components of mineral content: illite, chlorite, smectite, kaolinite, quartz and unidentified high susceptibility phase make an AMS interpretation of this content ambiguous. However, this method may be useful for tracing early diagenetic geochemical/microbial processes where iron element is involved. Some sedimentary processes may be recognized from AMS when an assemblage of parameters is studied together: bulk susceptibility, the degree and the shape of anisotropy, principal directions, and the distribution of all these parameters within a set of specimens. Debris-flow processes, as well as lacustrine and floodplain sedimentation are especially well-defined in AMS results. Palaeotransport directions are ambiguous because studied rocks have undergone weak deformation what overprints this sedimentary feature. Most specimens represent an oblate shape of anisotropy and show a good correlation of minimum susceptibility axis and normal to bedding plane.
EN
The Hoanh Bo Basin is a multiple period formed basin which is associated with the tectonic mechanism due to the activity of the Chi Linh-Hon Gai and Trung Luong Faults during the late Paleogene – early Neogene time. The basin is filled with continental sediments, comprising mainly polymictic conglomerates, sandstones, siltstones, claystones and shales. Coarser-grained polymictic deposits predominate along the northern and western margins of the basin, while different types of siltstones, claystones, even sandstones occur in its center, as well as along its southern and eastern parts toward the Ha Long Bay. The source rocks for sedimentary materials are mainly originated from rocks of the Hon Gai and Ha Coi Formations. Based on the dominant grain-size class, texture, stratification, degree of clast rounding and sorting, 17 lithofacies were determined in the Hoanh Bo Basin infill. The basin is filled by gravelly, sandy and fine-grained lithofacies just covers a modest area but it represents a full of succession of 4 depositional systems including alluvial fan, fluvial, deltaic and lacustrine environments. Alluvial fan and fluvial environments are characterized by an assemblage of lithofacies such as sand- and mud-supported disorganized breccias (Gb), clast- to sand-supported conglomerates (Gmm), clast-supported inverse-graded conglomerates (Gig), planar-cross-bedded conglomerates (Gp), trough cross-bedded conglomerates (Gt), horizontally stratified conglomerates (Gh), planar cross-bedded sandstones (Sp), trough cross-bedded sandstones (St), ripple cross-laminated sandstones (Sr), horizontally bedded sandstones (Sh), massive sandstones (Sm), massive mudstones, siltstones (Fsm), laminated siltstones and mudstones (Fl), massive claystones (Fm) and coaly lithofacies (C); the deltaic assemblage is dominated by planar-cross-bedded conglomerates (Gp), horizontally stratified conglomerates (Gh), planar cross-bedded sandstones (Sp), horizontally bedded sandstones (Sh), low-angle cross-bedded sandstones (Sl); while the lacustrine assemblage consists of ripple cross-laminated sandstones (Sr), horizontally bedded sandstones (Sh), normally graded sandstones (Sng), massive mudstones, siltstones (Fsm), laminated siltstones and mudstones (Fl), massive claystones (Fm) and coaly lithofacies (C).
EN
The Orava-Nowy Targ Basin is an intramontane depression located at the border of the Inner and Outer Carpathians. It is filled mostly with fine-grained terrestrial and fresh-water deposits of Neogene and Quaternary age, which record the structural evolution and denudation processes of the surrounding regions: Orava, Podhale, and the Tatra Mts. The Orava-Nowy Targ Basin fill was studied in the Oravica River section, which reveals 90 m thick Neogene deposits and allows observation of their lateral diversity. Fifteen lithofacies and seven facies associations distinguished here document the depositional evolution of the basin fill, starting from hill-slope debris flow through silt turbidite-bearing lake, to flood-dominated fluvial plain, swamp and alluvial fan deposits, as well as a pyroclastic event. The palaeorelief was low during deposition and the Orava-Nowy Targ Basin could have spread significantly more to the south.
12
Content available remote Warunki rozwoju i wiek krasu w gipsach Niecki Soleckiej
PL
W neogeńskich gipsach Niecki Soleckiej występują następujące typy form krasowych: duże obniżenia krasowo-denudacyjne, krasowe (ślepe) doliny, leje oraz liczne, choć niewielkie jaskinie, stanowiące pojedyncze lub słabo rozgałęzione korytarze bądź komory (głównie typu branchwork i rudimentary branchwork). Większość z tych form reprezentuje epigenetyczny kras odkryty, który rozwinął się w czwartorzędzie i nadal jest aktywny. Największe obniżenia krasowo-denudacyjne zaczęły powstawać prawdopodobnie już w późnym neogenie. Rozwój form krasowych Niecki Soleckiej, w tym większości jaskiń, w warunkach krasu epigenetycznego różni ten region od zachodniej Ukrainy, gdzie w gipsach neogeńskich występują wielkie labiryntowe systemy jaskiniowe powstałe w wyniku głębokich przepływów międzywarstwowych. Na terenie Niecki Soleckiej tylko pojedyncze jaskinie reprezentują kras międzywarstwowy powstały w warunkach freatycznych, poniżej napiętego zwierciadła wód podziemnych, prawdopodobnie w późnym neogenie.
EN
A variety of types of karst forms has been identified in Neogene gypsum of the Niecka Solecka (Solec Basin), including large karstic-denudational depressions, karst (blind) valleys, sinkholes, and numerous but short and simple (branchwork and rudimentary branchwork type) caves. Most of these forms represent the epigenic, exposed karst, that developed during the Quaternary and is still active. The largest karst-denudational depressions could have started to develop in the Late Neogene. The epigenic character of karst forms (and most of caves) in gypsum of the Niecka Solecka makes this region distinctive from Western Ukraine, where large maze cave systems representing intrastratal karst occur. In the Niecka Solecka region only a few caves represent intrastratal karst formed in confined, freatic conditions probably in the Late Neogene.
PL
Celem przeprowadzonych prac było rozpoznanie i zbadanie profilu osadów paleogenu i neogenu, ze szczególnym uwzględnieniem młodszego neogenu, w miejscowości Łęczyce koło Lęborka, gdzie w odsłonięciu w skarpie pradoliny Redy-Łeby stwierdzono występowanie utworów neogeńskich. Posadowiony u podstawy odsłonięcia otwór wiertniczy Łęczyce-Tr osiągnął głębokość 110,0 m p.p.t. i został zatrzymany w utworach formacji mosińskiej dolnej z dolnego oligocenu. Próbki pobrane z odsłonięcia i z rdzenia wiertniczego wykorzystano do badań laboratoryjnych składu ziarnowego (133 analizy), węglanowości osadów (122 analizy), składu minerałów ciężkich (41 próbek) i badań zespołów sporowo-pyłkowych i fitoplanktonu (39 próbek). W profilu otworu wiertniczego rozpoznano osady dolnego oligocenu i miocenu odpowiadające formacjom: mosińskiej dolnej, czempińskiej i mosińskiej górnej (dolny oligocen), gorzowskiej i krajeńskiej (dolny/ środkowy miocen) oraz adamowskiej (środkowy miocen). Stwierdzone w profilu odsłonięcia osady plioceńskie uznano za ekwiwalenty formacji poznańskiej i gozdnickiej. Przeprowadzono korelację stratygraficzną rozpoznanej sukcesji z profilami z obszarów sąsiadujących na terenie północno-wschodniej Polski oraz z Półwyspu Sambijskiego. Wyniki badań umożliwiły odtworzenie warunków sedymentacji osadów, prześledzenie następstwa zbiorowisk roślinnych i implikujących je zmian klimatu. Ze względu na zachowanie pełnego profilu osadów kenozoicznych i stwierdzenie występowania osadów plioceńskich (jedyne stanowisko w tym rejonie), profil z Łęczyc uznano za referencyjny dla Pomorza Wschodniego.
EN
The reported study focused on a complex analysis of Paleogene–Neogene section located at Łęczyce near Lębork (Eastern Pomerania). The lower part of the section is represented by Lower Oligocene to Miocene deposits, drilled by the Łęczyce-Tr well to the depth of 110 m. Its upper part consists of the Late Neogene succession exposed in the slope of the Reda–Łeba palaeovalley just above the drill top. Both core and outcrop sections were sampled for analyses of grain size and composition (133 samples), carbonate content (122 samples), heavy mineral composition (41 samples), and spore-pollen and phytoplankton assemblages (39 samples). For the first time in the Eastern Pomerania, a succession of the standard Lower Oligocene to Pliocene formations has been identified in this section including the Oligocene to Miocene deposits represented by the Lower Mosina Fm., Czempin Fm., Upper Mosina Fm. (Lower Oligocene), Gorzów Fm. and Krajenka Fm. (Lower/ Middle Miocene) and Adamów Fm. (Middle Miocene). Outcrop of the Pliocene deposits (unique in the area), being an equivalent of the Poznań Fm., were described. All the distinguished units were correlated with corresponding sections from the north-eastern Poland and the Sambia Peninsula. The study results have enabled to reconstruct the sedimentary conditions and depositional environments, as well as the succession of floral communities that record the paleoclimatic changes. The Łęczyce section, comprising the Lower Oligocene to Pliocene deposits, is a representative section of the Paleogene–Neogene succession for the whole area of Eastern Pomerania.
PL
Badawczy otwór wiertniczy w Wysokiej Wsi, zlokalizowany w centrum Wzgórz Dylewskich (NE Polska), osiągnął głębokość prawie 490 m, z czego na ponad 400 m przewiercono utwory paleogenu i neogenu. W wyniku badań palinologicznych 47 próbek wyróżniono 13 zespołów palinomorf (sporomorfy, fitoplankton i zoomorfy) i datowano osady. Stwierdzono dwu- i trzykrotne powtarzanie się podobnych zespołów palinomorf w paleogeńskim i neogeńskim odcinku profilu, co wskazuje na silne glacitektoniczne zaburzenie osadów. Udokumentowana w wyniku badań palinologicznych skomplikowana budowa geologiczna odnacza się kilkoma strefami odkłucia i przemieszczenia pakietów skalnych. Najniższy, paleogeński kompleks znajduje się w położeniu pierwotnym, datowano w nim zespoły pyłkowo-fitoplanktonowe: D3–D4 – środkowy paleocen, utwory górnego paleocenu w facji lądowej i D8 – dolny eocen. Na głębokości ok. 455 m występuje pierwsza powierzchnia nieciągłości, gdzie w osady paleogeńskie został wprasowany ponad 100-metrowej miąższości pakiet osadów środkowego miocenu z poziomami sporowo-pyłkowymi V, VI, VIII, IX, XI. Kolejną powierzchnię odkłucia stwierdzono na głębokości ok. 339 m. Na osadach mioceńskich ponownie występuje ok. 60-metrowej miąższości pakiet utworów paleogeńskich, stratygraficznie młodszych od leżących w spągu, datowanych na podstawie poziomów pyłkowo-fitoplanktonowych – górnoeoceński poziom D12 i wykształcone w facji lądowej utwory dolnego oligocenu. W te paleogeńskie osady jest wprasowana kilkumetrowej miąższości seria osadów mioceńskich reprezentująca poziom sporowo-pyłkowy IX. Na głębokości ok. 240 m znów pojawiają się osady środkowomioceńskie ok. 150-metrowej miąższości z poziomami sporowo-pyłkowymi V, VII i IX. Stwierdzone mozaikowe następstwo warstw odzwierciedla skomplikowane procesy glacitektoniczne, które doprowadziły do powstania łusek glacitektonicznych budujących jądro moreny spiętrzonej Wzgórz Dylewskich. W wyniku badań palinologicznych uzyskano unikatowe dane, pozwalające na lokalizację stref odkłuć glacitektonicznych. Brak osadów czwartorzędowych w jądrze moreny spiętrzonej wskazuje na wczesnoplejstoceński wiek deformacji.
EN
The Wysoka Wieś borehole located in the center of Dylewskie Hills (NE Poland) reached a depth of almost 490 metres, with more than 400 metres of the Paleogene and the Neogene deposits. Palynological studies were designed to determine whether this huge Paleogene and Neogene sedimentary complex is located in situ or it has been glacitectonically redeposited. Forty-seven samples were analysed for all palynological matter components, i.e. palynomorphs (sporomorphs, phytoplankton, zoomorphs), palynoclasts (phytoclasts) and inorganic debris. Among the palynomorphs, 13 assemblages have been distinguished. Describing these assemblages from the bottom to the top of the section, dual or triple repetition of the same palynomorph zones indicates a strong glacitectonic deformation of the sediments. Palynological data evidence several disengagement zones and displacement of rock packages. The lowest sedimentary complex occurs in the primary position and it contains the pollen and phytoplankton assemblage D3–D4 of the Middle Paleocene to the Upper Paleocene (terrestrial facies), and the Lower Eocene assemblage D8. At a depth of ca. 455 m there is the first discontinuity zone, along which the over 100-metres thick package of Middle Miocene sediments, containing pollen zones V, VI, VIII, IX and XI, became intruded/ pressed into the Paleogene deposits. The next disengagement zone occurs at a depth of ca. 339 m, where the Miocene sediments are overlain by a about 60-metres thick package of Paleogene deposits dated with the stratigraphically younger pollen and phytoplankton zones D12 of the Upper Eocene and Lower Oligocene (terrestrial facies). These Paleogene deposits were intruded by the Miocene series, a few metres thick, representing pollen zone IX. Then, at a depth of 240 m, occurs the Middle Miocene sedimentary complex, ca. 150 m thick, with pollen zones V, VII and IX. The complicated glacitectonic processes caused such mosaic succession, reflecting the slice structure of glaciotectonic thrust moraines. Palynological studies provided unique data to define the glaciotectonic disengagement zones. The absence of Quaternary deposits in the internal moraine structure indicates the Early Pleistocene age of deformation.
EN
The central (Paleozoic) and the south-western (Permian-Mesozoic) parts of the Holy Cross Mts. region are areas of typical structural morphology controlled by fold-type tectonic structure and lithology. In the northern (Mesozoic) marginal part of the region structural arrangement of main relief elements is not so clear due to the block-type tectonics, however, some morphological features, such as the valley network, elongation of glacial, kame-type landforms and orientation of rock cliffs are related to joint system. The general relief elements of part of the Nida Basin region adjoining the Holy Cross Mts. are of noeotectonic origin, while the subordinate landforms represent typical structural morphology. The role of recent tectonic factor should be also taken into account in the Holy Cross Mts., however, the identification of tectonic influence on the current relief of this region is very difficult.
EN
The aim of the study was to determine the maturity of organic matter in the Neogene sediments of the Orava-Nowy Targ Intramontane Basin and to estimate, according to vitrinite reflectance (Ro), maximum paleotemperatures affecting studied sediments. The area of research is located in southern Poland and northern Slovakia, on the boundary between the Inner and Outer Carpathians. The Neogene and Quaternary deposits, which are filling the basin, discordantly overlie folded strata of the Magura Nappe (Outer Carpathians), Podhale flysch (Inner Carpathians) and Pieniny Klippen Belt (Birkenmajer 1979). The analysis was performed on eleven miocene claystone and coal clay samples collected from four outcrops in Polish part of the basin and one outcrop in Slovak part of the basin. Microscope analysis of organic matter in reflected white light was carried out for each sample. Random reflectance of huminite was measured under oil immersion on randomly oriented grains using Zeiss Axioplan microscope in reflected monochromatic non-polarised light. The values of Ro were converted into paleotemperatures according to Barker & Pawlewicz (1986) equation. It was not possible to calculate paleotemepratures in ten samples due to low maturity of organic matter and to low carbonization degree of coal. Only for one claystone sample from Chochołów reflectance of vitrinite measurement was positive. The value of Ro for analyzed sample was 0.366%, which indicate paleotemeprature of about 25°C (early stadium of diagenesis). Previous analysis of the organic matter in the studied area was carried out by Nagy (1996). Comparison of the results of the measurements of the vitrinite reflectance in the mentioned article match the values described in this study. However the temperatures associated with the burial history proposed by Nagy (1996), do not correlate with the temperatures calculated from the equation of Barker & Pawlewicz (1986). Due to the temperature differences it is problematic to correspond with the burial history of studied area proposed by Nagy (1996).
EN
The Yishu Fault Zone runs through the centre of Shandong Province (E China); it is a deep-seated large fault system that still is active. Two volcanic faulted basins (the Shanwang and Linqu Basins) in the Linqu area, west of the fault zone, are exposed to rifting, which process is accompanied by a series of tectonic and volcanic earthquakes with a magnitude of 5–8. Lacustrine sediments in the basins were affected by these earthquakes so that seismites with a variety of softsediment deformation structures originated. The seismites form part of the Shanwang Formation of the Linqu Group. Semi-consolidated fluvial conglomerates became deformed in a brittle way; these seismites are present at the base of the Yaoshan Formation. Intense earthquakes triggered by volcanic activity left their traces in the form of seismic volcanic rocks associated with liquefied-sand veins in the basalt/sand intercalations at the base of the Yaoshan Formation. These palaeo-earthquake records are dated around 14–10 Ma; they are responses to the intense tectonic extension and the basin rifting in this area and even the activity of the Yishu Fault Zone in the Himalayan tectonic cycle.
19
Content available remote Evidence of soils and paleosols in the Poznań Formation (Neogene, Polish Lowland)
EN
A succession of stacked paleosol profiles was recognized in open pits in the western Wielkopolska region (Poland). Field observations and micromorphological studies made it possible to distinguish the following pedostructures, formed in contrasting environments: soil horizons, crystallaria, concretions, redoximorphic structures, Fe-Mn globulae and slickensides. In both soils (Holocene) and paleosols (Pleistocene or/and Pliocene?), surface horizons are present (horizon A), marked by rhizocretions. There are two separate carbonate soils. One of them contains calcite concretions and gypsum pedofeatures, presumably formed in arid or semi-arid conditions. Two of the soil profiles are probably truncated, and only subsurface horizons are present (horizon B). In some cases, paleosols are separated by sediment layers slightly influenced by pedogenesis (horizon BC). Carbonate soils (Bk) indicate water deficit during their formation. The presence of horizons with slickensides (Bss) indicates intervals with contrasting seasonal climates (wet and dry cycles). The profiles were influenced by gleying processes which caused redistribution of iron oxides and formation of iron and iron-manganese concretions. The pedostructures recognised reflect different climatic conditions as well as humidity changes during the time of their formation.
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.
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