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EN
The key aspect for evaluation of potential effects of ongoing environmental changes is identification of their controlson one hand, and understanding of their mutual relations on other. In this context, the best source of information about medium and long term coThe key aspect for evaluation of potential effects of ongoing environmental changes is identification of their controlson one hand, and understanding of their mutual relations on other. In this context, the best source of information about medium and long term consequences of various environmental processes is the geologic record. Numerous different-scale palaeoenvironmental events took place during the Jurassic/Cretaceous transition; amongst them, the best documented so far are: long term marine regression during the Tithonian-early Berriasian, climate aridization during the late Tithonian-early Berriasian, and tectonic activity in western parts of the Neo Tethys Ocean during the late Berriasian-Valanginian. This study, which is based on the Ph Ddissertation of Damian Gerard Lodowski, attempts to reconstruct the latest Jurassic-earliest Cretaceous paleoenvironment and its evolution in the area of the Western Tethys, with special attention paid to cause-and-effect relationships between climate changes, tectonic activity and oceanographic conditions (perturbations in marine circulation and bioproductivity). Here are presented the basic results of high-resolution geochemical investigations performed in the Transdanubian Range (Hárskút and Lókút, Hungary), High-Tatric (Giewont, Poland) and Lower Sub-Tatric (Pośrednie III, Poland) series, Pieniny Klippen Belt (Brodno and Snežnica, Slovakia; Velykyi Kamianets, Ukraine) and Western Balkan (Barlya, Bulgaria) sections. The sections were correlated and compared in terms ofpaleoredox conditions (authigenic U), accumulation of micronutrient-type element (Zn) and climate changes (chemical index of alteration, CIA), providinga consistent scenario of the Tithonian-Berriasian palaeoenvironment evolution in various western Tethyan basins. Amongst the first-order trends and events, characteristic of studied sections are the two intervals recording an oxygen deficient at the seafloor: 1) the upper Tithonian-lowermost Berriasian (OD I); and 2) at the lower/upper Berriasian transition (OD II). Noteworthy, this phenomena cooccurred with elevated accumulations of nutrient-type elements (i. e. enrichment factor of Zn). Besides, collected data document the late Tithonian-early Berriasian trend of climate aridization, as well as the late Berriasian humidification. Such record is explained by a model, in which decreasing intensity of atmospheric circulation during the late Tithonian-early Berriasian was directly connected with climate cooling and aridization. This process resulted in lesser efficiency of up- and/or downwelling currents, which induced sea water stratification, seafloor hypoxia and perturbations in the nutrient-shuttle process during the OD I. On the other hand, the OD II interval may correspond to tectonic reactivation in the Neo Tethyan Collision Belt. This process might have led to physical cutoff of Alpine Tethys basins from the Neo Tethyan circulation (both atmospheric and oceanic), driving the limited stratification in the former, and limiting the effect of gradual humidification of global climate (i.e. due to increasing strength of monsoons and monsoonal upwellings). nsequences of various environmental processes is the geologic record. Numerous different-scale palaeoenvironmental events took place during the Jurassic/Cretaceous transition; amongst them, the best documented so far are: long term marine regression during the Tithonian-early Berriasian, climate aridization during the late Tithonian-early Berriasian, and tectonic activity in western parts of the Neo Tethys Ocean during the late Berriasian-Valanginian. This study, which is based on the Ph Ddissertation of Damian Gerard Lodowski, attempts to reconstruct the latest Jurassic-earliest Cretaceous paleoenvironment and its evolution in the area of the Western Tethys, with special attention paid to cause-and-effect relationships between climate changes, tectonic activity and oceanographic conditions (perturbations in marine circulation and bioproductivity). Here are presented the basic results of high-resolution geochemical investigations performed in the Transdanubian Range (Hárskút and Lókút, Hungary), High-Tatric (Giewont, Poland) and Lower Sub-Tatric (Pośrednie III, Poland) series, Pieniny Klippen Belt (Brodno and Snežnica, Slovakia; Velykyi Kamianets, Ukraine) and Western Balkan (Barlya, Bulgaria) sections. The sections were correlated and compared in terms ofpaleoredox conditions (authigenic U), accumulation of micronutrient-type element (Zn) and climate changes (chemical index of alteration, CIA), providinga consistent scenario of the Tithonian-Berriasian palaeoenvironment evolution in various western Tethyan basins. Amongst the first-order trends and events, characteristic of studied sections are the two intervals recording an oxygen deficient at the seafloor: 1) the upper Tithonian-lowermost Berriasian (OD I); and 2) at the lower/upper Berriasian transition (OD II). Noteworthy, this phenomena cooccurred with elevated accumulations of nutrient-type elements (i. e. enrichment factor of Zn). Besides, collected data document the late Tithonian-early Berriasian trend of climate aridization, as well as the late Berriasian humidification. Such record is explained by a model, in which decreasing intensity of atmospheric circulation during the late Tithonian-early Berriasian was directly connected with climate cooling and aridization. This process resulted in lesser efficiency of up- and/or downwelling currents, which induced sea water stratification, seafloor hypoxia and perturbations in the nutrient-shuttle process during the OD I. On the other hand, the OD II interval may correspond to tectonic reactivation in the Neo Tethyan Collision Belt. This process might have led to physical cutoff of Alpine Tethys basins from the Neo Tethyan circulation (both atmospheric and oceanic), driving the limited stratification in the former, and limiting the effect of gradual humidification of global climate (i.e. due to increasing strength of monsoons and monsoonal upwellings).
EN
Widely distributed freshwater carbonate sediments, i.e., limestone, dolomitic limestone and dolomite, developed in inter-dune alkaline ponds of the Danube-Tisza Interfluve in the centre of the Carpathian Basin during the Holocene. The key parameters that determine the formation of any given type of carbonate mineral (calcite, dolomite) are temperature, evaporation rate, pH and ion concentrations, in addition to CO2 absorption by aquatic plants. CT analysis is capable of recording small-scale density variations attributable to compositional differences of sedimentary rocks. As the type and proportion of rock-forming minerals and other components is an artifact of past environmental and climatic conditions, CT values may act as potential palaeoenvironmental proxies. The present study compares variations in rock-forming components obtained for freshwater carbonates utilizing the CT method with already available geochemical and palaeoecological proxy data. Variations in molluscan ecology and isotope geochemistry, sedimentation times and CT-based rock density values all indicate the relevance of millennial-scale, climate-driven changes in carbonate formation. As previously observed, the emergence of colder conditions in the North Atlantic, which resulted in increased cyclonic activity and heavier rainfall in western Europe and the Danube watershed area between 10.3 and 9.3 kyr cal BP, resulted in the emergence of humid conditions favouring a rise in the groundwater table at our site and precipitation of calcite from pore waters as opposed to high-magnesium calcite. This is clearly reflected in a negative shift in CT density values in our dated rock samples.
EN
Phymatellid demosponges are common fossils in the Campanian deposits of central Europe. In Poland, the Campanian phymatellids were known mostly from the opoka facies of the Miechów Synclinorium (southern Poland), where they occur mainly in the characteristic horizons of siliceous nodules in the lower Campanian opoka succession. Similarly preserved early Campanian phymatellids were identified in a redeposited lithistid assemblage in the Neogene gravels, exposed in the Bełchatów Lignite Mine (Mogilno-Łódź Synclinorium, central Poland). Rare phymatellids were noted for the first time in the upper Campanian gaize of the Miechów Synclinorium. The taxonomic descriptions of 16 phymatellid species presented here, including one new species, Kalpinella fragilis, completes existing knowledge of the taxonomic diversity of these sponges in the Late Cretaceous basins of central Europe. The present study also supplements the data on the stratigraphic ranges and spatial distribution of these species. The palaeoecology of Cretaceous phymatellids is discussed on the basis of their occurrence in the various facies.
EN
The current paper presents the results of palynological studies from deep structures at the front of the Carpathian overthrust, penetrated by the NS-1 Borehole. Both the method used and hardly accessible material from a depth of almost 5.5 km allow the presentation of new data from the Stebnik Unit, the underlying autochthonous Miocene succession, and the conglomerates that rest upon the crystalline basement. Samples collected from available cored intervals and cuttings from the lower part of the borehole provided the opportunity to study for the first time the palynological content of the strata under consideration. Samples yielded diversified material, composed of terrestrial and marine elements, commonly showing various stages of preservation. The latter indicate various origins for the material analysed, which is possibly at least partly recycled. The occurrence of this phenomenon, particularly in the Stebnik Unit and the upper part of the autochthonous Miocene sequence, confirmed also by results of earlier micropalaeontological studies, makes precise stratigraphic correlation highly debatable. The authors discuss the possibility of both Paleogene and Miocene ages for the material. Also highly debatable are the palaeoenvironmental reconstructions of this interval, although the general intense influx of terrestrial material recorded is probably responsible for the unfavourable conditions for planktonic biota. Different, optimal marine conditions can be deduced for the lower part of the autochthonous Miocene; an abundance of dinoflagellate cysts allows their precise correlation with coeval strata of the Carpathian Foredeep Basin. Palynological analysis of conglomerate matrix material gave negative results. However, this and the lithological characteristics indicate a different origin and age of these strata in comparison with other coarse-grained lithosomes, known from neighbouring areas. The generally immature state of preservation of the organic matter in the deepest part of the borehole indicates that this part of the succession was not affected by the high temperatures that would be expected at such a depth. This contrast with the much more mature palynomorphs of the overlying Stebnik Unit points to the fact that these strata were heated to a much higher degree prior to their final burial.
EN
The palaeoecology and palaeoenvironments of the lower–middle Miocene succession in Gebel Gharra, NW of Suez, Egypt, are interpreted, on the basis of a detailed study of microfacies, trace fossils, and macrofaunal benthic assemblages. This succession consists of a lower siliciclastic part (the Gharra Formation) and a carbonate-dominated upper part (the Geniefa Formation), corresponding to a general transgression-regression cycle. Facies characteristics indicate depositional palaeoenvironments, ranging from supratidal, lagoonal, to shoal settings on an inner ramp that was influenced proximally by clastic input. At least seven ichnotaxa were recorded in the lower Miocene Gharra Formation, representing suites of the Skolithos ichnofacies. Among them, the ichnogenus Polykladichnus is recorded for the first time in Egypt. The macrobenthic taxa identified in 13 statistical samples are grouped into five assemblages (A–E) that are described and interpreted as the remains of communities. The faunal distribution and trophic structure of most of these assemblages confirm the existence of relatively stable and low-stress conditions. However, the trophic structure of the assemblages reflects the influence of particular environmental parameters, the dissolution of aragonitic shells and/or sample-size effects. Environmental parameters, controlling the distribution of trace and/or body fossils, include substrate consistency, bathymetry, water energy, productivity level, rate of sedimentation, salinity, and oxygen availability. The results of integrated lithoand biofacies analysis confirm that the succession studied was deposited in different environmental settings, providing perfect conditions for the occurrence and preservation of trace-fossil and macrobenthos assemblages.
EN
The crystallization of speleothems can be interrupted by the invasion of allogenic water into cave passages. These interruptions were studied, both in speleothems currently submerged in an underground river and in speleothem sections, which were found at the lowermost fluvially active passage level of the Demänová Cave System. The interaction between speleothems and allogenic water, undersaturated with respect to calcite, is manifested in the presence of siliciclastic material and the corrosion of calcite crystals. The progressive development of corrosion features depends on the duration of the interaction of calcite crystals with allogenic water. Moreover, the movement of the water and siliciclastic deposition over the speleothems can influence the corrosion process. The estimated rate of corrosion, caused by the underground Demänovka River and measured by the weight loss of experimental tablets, is up to 0.029 mm/y. U-series dating indicated that the interaction of speleothems with allogenic water occurred during the Vistulian (Weichselian). The identification of corrosion episodes, caused by allogenic water, is a step towards understanding the origin of hiatuses and establishing criteria for recognition of them.
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
We provide the first reports of some rare trace fossils from the middle Turonian (Upper Cretaceous) of the Sudety Mountains (SW Poland, Upper Nysa Kłodzka Graben, Długopole Górne Quarry). These include burrows ?Ancorichnus isp., Asterosoma cf. ludwigae Schlirf, 2000, Asterosoma isp., cf. Phycodes isp., Dactyloidites ottoi (Geinitz, 1849), Funalichnus strangulatus (Fritsch, 1883), Phycodes cf. palmatus (Hall, 1852), cf. Phycodes isp., Phycosiphon incertum Fischer-Ooster, 1858, ?Phycosiphon isp., Planolites beverleyensis (Billings, 1862) and borings Entobia isp. Some body fossils, bivalves ?Brachidontes sp., Lima canalifera Goldfuss, 1836, Pinna (Pinna) cretacea (Schlotheim, 1813) and Rhynchostreon suborbiculatum (Lamarck, 1801) are also reported. The trace fossil assemblage indicates a distal Skolithos ichnofacies and proximal Cruziana ichnofacies, which characterize a proximal and distal lower shoreface setting respectively. Sedimentation of the middle Turonian sandstones took place in a shallow epicontinental sea of normal salinity and a soft substrate, which was well-oxygenated under low-moderate hydrodynamic conditions. The presence of the oyster Rhynchostreon in the deposits studied suggests the influence of a warm Tethys Ocean.
EN
Seven Middle Miocene (Upper Badenian to Lower Sarmatian) sedimentary sections of the Central Paratethys, two from the Polish Carpathian Foredeep Basin (PCFB) and five from the Eastern Carpathian Foreland Basin (ECFB) of Romania and the Republic of Moldova have been analysed micropalaeontologically to better constrain the Badenian-Sarmatian Extinction Event, characterized by significant taxonomic impoverishment of both foraminifers and ostracods. Our studies show significant palaeoenvironmental changes in the basin including depth, salinity, oxygenation, and organic matter flux. The occurrence of moderately diverse planktonic foraminifera (Globigerina, Globigerinita, Globorotalia, Trilobatus, Orbulina, Velapertina) in the Upper Badenian deposits of the PCFB as well as in the ECFB and their rarity in the lowermost Sarmatian indicate an almost fully marine environment during the latest Badenian, followed by a significant regression and possible appearance of much more restricted marine conditions across the boundary. The taxonomic composition of the Sarmatian foraminifera, ostracoda and calcareous nannofossils indicate that during this interval the salinity fluctuated strongly, with the water regime varying from brackish to normal marine. In addition, the identified micropalaeontological assemblages identified show palaeoenvironmental similarity across different basins of the Central Paratethys. This supports a hypothesis of possible connections during the latest Badenian between different areas of the Central Paratethys, as well as of the existence of a gateway between the Central Paratethys and the Mediterranean realm.
EN
In the sandstones and conglomerates of the Idzików Conglomerate Member (Coniacian), exposed in the Idzików Quarry (SW Poland, Upper Nysa Kłodzka Graben), a moderately diverse assemblage of trace fossils has been recognized. The trace fossils include Arenicolites isp., Asterosoma isp., ?Bergaueria isp., Cylindrichnus isp., Conichnus conicus, Curvolithus simplex, Dactyloidites ottoi, Diplocraterion parallelum, ?Diplocraterion isp., Gyrochorte isp., Gyrophyllites aff. kwassizensis, Macaronichnus segregatis, Ophiomorpha nodosa, Ophiomorpha isp., ?Palaeophycus isp., ?Rhizocorallium isp., Rosselia isp., ?Scolicia isp., Teichichnus isp. and Thalassinoides isp. Escape traces (fugichnia) and some unidentified trace fossils also were found. The following ichnoassociations are distinguished: (IA1) Ophiomorpha-Cylindrichnus, (IA2) Asterosoma-Conichnus and (IA3) Ophiomorpha- Arenicolites. IA1 probably represents a mixture of the impoverished proximal Cruziana ichnofacies and the distal Skolithos ichnofacies, which points to the lower, weakly storm-affected shoreface. IA2 is interpreted as the archetypal Skolithos ichnofacies (opportunistic colonization of tempestite beds) with some elements of the Cruziana ichnofacies (bioturbated, fair-weather background deposits) in the middle, moderately storm-affected shoreface. IA3 is assigned to the archetypal Skolithos ichnofacies, which indicates the upper shoreface-foreshore settings. The trace-fossil evidence implies that the Upper Cretaceous succession was deposited in a shallow, open basin with good oxygenation of the sea floor and normal salinity, under low- to moderately high-energy hydrodynamic conditions. On the basis of ichnological and sedimentological analyses, the deposits studied originated in a system of fan-delta and shallow-shelf settings with common transitional-proximal tempestites. They were deposited in the eastern part of the Upper Nysa Kłodzka Graben during the Coniacian regression.
EN
Borehole K-1 is an exploratory well that was drilled in the North Makassar Basin (West Sulawesi) in 2011. Gas chromatography (GC) and gas chromatography-mass chromatography (GC-MS) analyses have been conducted on extracts from well cuttings from the Paleogene to Neogene interval in order to investigate the characteristics of biomarkers present. Although the well was drilled with oil-based mud and gas chromatographic analysis reveals that the alkane fractions are heavily contaminated, detailed investigation of biomarkers in these rock extracts and comparison with biomarkers in the oil-based mud has revealed that, while there are hopane and sterane biomarkers in the mud, there are also a discrete set of biomarkers that are indigenous to the rocks. These include oleanane, bicadinanes, taraxastane and other higher-plant-derived triterpanes. The presence of these compounds in environments that range from bathyal to marginal marine and even to lacustrine, shows the extent of reworking of terrestrial material into aquatic settings in this region during the Paleogene and Neogene and provides further evidence of a predominance of terrestrial material, even in deep-marine settings, with little ‘in-situ’ material noted. These findings have important implications for the use of biomarkers as indicators of palaeoenvironment in both source rocks and oils.
EN
The Upper Turonian to Middle Coniacian (Upper Cretaceous) succession of the Babadag Basin (North Dobrogea, Romania) constitutes an apparently continuous fossiliferous carbonate succession. The presence of moderately rich inoceramid, ammonite and foraminiferal assemblages allows for the application of a precise biostratigraphic subdivision. The palaeoenvironmental conditions and evolution of the Babadag Basin during the Late Turonian-Middle Coniacian are inferred using microfacies analysis and foraminiferal spectra. Together, these suggest the Turonian-Coniacian Badabag Basin reflects relatively shallow-water conditions in a near-shore environment, punctuated by two regression events in the Late Turonian and in the Middle Coniacian.
EN
A new ichnogenus and ichnospecies Rosarichnoides sudeticus is proposed for a large, exceptionally well-preserved crustacean burrow, which has been found in the Upper Cretaceous (Coniacian) Quadersandstein of the North Sudetic Synclinorium (Czaple quarry). Some of its specimens have been assigned to Thalassinoides saxonicus (Geinitz, 1842). It is unbranched, a characteristic rosary-shaped trace fossil, which consists of alternating chambers (swellings) and constrictions. The burrow is without any wall and usually lack ornamentation and has a passive fill. It should be included in ophiomorphid group sensu Bromley (1996). This unique finding resembles modern crustacean burrows produced by shrimps or crabs. Additionally, Thalassinoides paradoxicus (Woodward, 1830), the starfish Astropecten scupini Andert, 1934, the inoceramids Inoceramus kleini Müller, 1888 and Inoceramus sp. were found in the same sandstones. The trace fossils are indicative of the archetypal Skolithos ichnofacies that is typical of foreshore to middle shoreface settings.
EN
The Sarcheshmeh and Sanganeh formations are the Lower Cretaceous deep marine sequences of the Koppeh-Dagh sedimentary basin, which revealed a diverse assemblage of dinoflagellates. The paper discusses palynostratigraphy, palynofacies and palaeoenvironment of these rock units in a borehole drilled in the eastern part of this basin. Ninety-five ditch-cutting samples were prepared and studied palynologically, which resulted in recognition of 76 species of dinoflagellate cysts belonging to 29 genera. The recorded assemblages are in accordance with the Odontochitina operculata Zone suggesting a Barremian?–Aptian age for the formations. Palynological data extracted led to identification of five palynofacies types based on the categories of Tyson (1995). These indicate a marginal, proximal and distal shelf environment of deposition. The obtained data from calculated palaeoecological factors revealed a gradual sea level rise during the deposition of these rock units, resulting in replacement of the oxic/dysoxic Sarcheshmeh Formation by the dysoxic/anoxic Sanganeh Formation.
EN
Zooxanthellate corals in the Badenian (Langhian to lower Serravallian) of western Ukraine occur in different lithofacies, but are most abundant in the upper Badenian coralgal reefs of the Ternopil Beds. The coral assemblage consists of five genera, with two predominant (Tarbellastraea and Porites) and three strongly subordinate (Favia, Heliastraea, Siderastrea). The present study is the first record of Heliastraea defrancei in the Fore-Carpathian Basin. The taxonomic composition of the corals indicates that their development occurred in conditions of some ecological stress, most probably connected with climate (location at the northern limit of coral distribution) and sedimentary environment (possible influx of terrigenous material). The coral assemblage shows similarities to numerous fossil reefs of Miocene age from the Paratethyan and Mediterranean realms.
EN
The Stajnia Cave is one of the most important archaeological sites due to the finds of the first remains of Neanderthals in Poland, and several tens of thousands of flint artefacts from the Middle Palaeolithic. Based on geological, geochemical, palaeobotanical, palaeozoological, archaeological and isotope analyses, coupled with absolute age determinations (OSL, U-Th and C14), 15 lithostratigraphic layers were distinguished and palaeoenvironmental conditions during the sedimentation of these beds were determined. The cave loams accumulated through weathering, aeolian and fluvial processes. Their age may be correlated with an interval from the Early Glacial to the Late Pleniglacial of the Visulian (Weichselian) Glaciation. Archaeological relics related to the Neanderthals have been discovered in layer D with an absolute age of about 52,000–45,000 years BP and correlated with MIS 3 – the Middle Plenivistulian (Interplenivistulian). Climate oscillations in the Vistulian are reflected by the type of the sediments and their physical-chemical features, allowing determining warmer interstadial and colder stadial periods. Generally, the climate was cold, characteristic of tundra areas with a typical vegetation and fauna, and with the mean temperature of the warmest month not exceeding 12°C. Based on multi-proxy studies it can be concluded that from layer E1 upwards, the climate conditions became progressively drier. At that time, the climate was cold with continental features enhancing tundra domination. This conclusion is confirmed by palaeontological investigations and the record of stable oxygen isotopes in the teeth of reindeer. The studies have also indicated seasonal migration of reindeer on the tundra that surrounded the cave. Probably, short-term slight climate warmings occurred during the Middle Plenivistulian (Interplenivistulian).
EN
Upper Campanian–Maastrichtian sections on the western flank of the Hun Graben in the Western Sirte Basin (WSB) are displaying two major type facies based on the foraminiferal assemblages. The first one indicates open-marine to outer-shelf conditions, and is represented by numerous bathy-pelagic planktonic foraminiferal species referable to the Radotruncana calcarata, Globotruncana aegyptiaca and the lower part of the Gansserina gansseri Zone (all late Campanian).The second type facies indicates an inner-shelf environment and is represented in the middle-upper part of the Gansserina gansseri Zone (early Maastrichtian) and Racemiguembelina fructicosa (late Maastrichtian) dominated by epi-pelagic planktonic and large benthic foraminifers. Large benthic foraminiferal index species Siderolites calcitrapoides Lamarck and Omphalocyclus macroporus (Lamarck) occur in abundance by the middle–late Maastrichtian. Correlation between planktonic foraminiferal zonation and large benthic foraminiferal zonation is given. An open-marine to outer-shelf environment passed into shallower marine conditions during the late Campanian–early Maastrichtian to late Maastrichtian, then a slight deepening and again shallowing is noticed.
EN
Coal beds could contain various amount of methane. This attribute might be dangerous in shafts or quarrying. Among other things, the works in the coal beds, including drilling, potentially there is a risk of exceeding the methane lower explosive limit. But on the other hand it is a source of unconventional hydrocarbon accumulations. In this paper geochemical characteristic of organic matter of tertiary brown coal from central part of Poland were performed. Geochemical surveys helps to know about genesis of methane from study area. The analysed samples contain various quantity of organic carbon, from 20,74 to 71.93 wt. %. Lignite from examine samples have weak hydrocarbon potential. In tertiary sediments prevails III type of kerogen with admixture of II type of kerogen. The thermal maturity of the tertiary organic matter changes within the interval from 354 to 419 in Tmax scale. Organic matter is immature. The composition of bitumens is different in various part of study area. Elemental analysis confirm that brown coal was comprised mostly by humic-group macerals. Coal samples contain methane with mixed genesis.
EN
Up to now only little attention was dedicated to the study of the trace fossils in the development of the Central Carpathian Paleogene Basin in the Orava region. Occasional trace fossils findings from the Central Carpathian Paleogene formations in the Orava and others regions were referred by Plička (1987). Other specialized works on trace fossils from these formations from the Orava region were not published. Study of trace fossils is strongly influenced by the existence of well exposed outcrops within individual formations. The best exposed outcrops are situated in the basal Borové Formation as well as in the higher parts of Paleogene sequences – mainly in the Zuberec Formation. This preliminary study shows a relatively rich diversity of trace fossils associations across the Central Carpathian Paleogene Basin. We present new finds of trace fossils, within which we have classified 7 ichnogenera, 11 ichnospecies and 2 types of trace fossils, which were not closely systematically classified. Many trace fossils identified in the Orava region are typical for some palaeoenvironments, which are characterized by a specific lithology, nature of the substrate, dynamics of the environment, amount of nutrients and stability or fluctuations of oxygen in the bottom waters. The trace fossils assemblages reflect changes of depositional systems during the tectonic and sequence stratigraphic development of the basin. Early Eocene shallow-sea environment of the Borové Formation including the rocky coast, sandy dynamic littoral, transition - al and internal shelf zones are characterized by findings of traces of Entobia, Gastrochaenolites, Nummipera, Ophiomorpha and Skolithos. On the contrary, a significant deepening of the deposition environment during the Oligocene, documented by turbidite sedimentation of Zuberec and Biely Potok formations is characterised by findings of graphoglyptids ( Spirorhaphe, Nereites, Paleodiction, Protopaleodictyon, Megagrapton ) or traces of deposit feeders ( Arthrophycus, Chondrites, Planolites, Phycodes, Scolicia, Zoophycos).
EN
The paper presents the data on an Eemian–Late Glacial sedimentary sequence from the Zwierzyniec site, central Poland. A number of boreholes document one or two organic layers that occur beneath one or two horizons of clayey and silty deposits of ice-dammed lakes. This study demonstrates to which extent the Zwierzyniec site can contribute to a better understanding of the palaeoenvironmental changes during the Eemian–Vistulian time-frame in central Poland. To study it, a multi-proxy approach was applied, involving: palynological and plant macrofossil analysis, study of rounding of quartz grains and morphology of their surface, and investigations of sand mineralogy and till petrography. The results show that a till bed is overlain by a sandy series corresponding to the glacial-interglacial transition. Either one or two distinct peaks of organic accumulation are evidenced by peat horizons. The lower horizon records spectra with hazel and hornbeam, and did, therefore, accumulate in the Eemian. Observed only in some boreholes, the upper peat horizon marks the Brørup (or the lower part of the Rederstall stadial) represented by forest-steppe conditions with patchy mosaics of larch and further transition into sedges and herbaceous taxa. Localized in between the two peat sequences, the sandy horizon marks a long-lasting aeolian transformation with weathering by frost in the Early Vistulian. Again, significant changes of the palaeoenvironmental regime occurred, and are manifested in the one or two horizons of the glaciolacustrine sediments. This corresponded to the last glaciation in the region, when the ice-dammed lakes formed during the Main Stadial.
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