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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).
PL
Artykuł prezentuje próbę przeprowadzenia analizy chemostratygraficznej dla różnowiekowych skał budujących górotwór karpacki. W pierwszej kolejności zdecydowano się stworzyć syntetyczny profil geologiczny dla osadów występujących we wschodniej części polskich Karpat. Wykorzystane próbki, w większości piaskowce, pochodziły z głównych poziomów stratygraficznych w obrębie jednostek skolskiej i śląskiej, gdzie zidentyfikowano skały od dolnej kredy po paleocen. Ze względu na dostępność materiału badawczego do badań wytypowano próbki o udokumentowanej stratygrafii z dwóch otworów, D-1 i H-1, zwracając głównie uwagę na ich klasyfikację stratygraficzną. Następnie dla porównania wykonano profil chemostratygraficzny dla otworu Kuźmina-1. Stwierdzono obecność bardzo dużego zróżnicowania składu chemicznego pomiędzy głównymi poziomami stratygraficznymi wyróżnianymi na podstawie badań paleontologicznych w badanych otworach, co pozwoliło wyznaczać zdecydowane granice pomiędzy poszczególnymi poziomami stratygraficznymi. Możliwość stworzenia unikalnych modeli chemostratygraficznych dla czterech analizowanych poziomów stratygraficznych: kredy górnej – senonu (warstwy inoceramowe), kredy górnej / paleocenu (warstwy istebniańskie), eocenu (warstwy pstre) oraz oligocenu (warstwy krośnieńskie) potwierdziło również wykonanie diagramu klasyfikacyjnego Herrona. Największe zróżnicowanie cech chemostratygraficznych uzyskano w przypadku utworów kredowych. Wstępnie badania wykonano w laboratorium akredytowanym Actlabs, tak aby móc później przeprowadzić ewaluację wyników uzyskanych za pomocą przenośnych spektrometrów (pXRF Titan, o zakresie pomiarowym od Mg do U, oraz pXRF Tracer, który umożliwia również pomiar zawartości Na, oba aparaty firmy Bruker). Potwierdzono, że wyraźne zróżnicowanie zawartości poszczególnych pierwiastków widoczne jest zarówno dla pierwiastków głównych, jak i śladowych. Pierwiastki najbardziej diagnostyczne to Na, Mg, Fe, K, Ca, również Si, choć w tym przypadku zakres zmienności jest nieco mniejszy. W przypadku pierwiastków śladowych są to S, P, Mn, Ti, Sr, Zr, Ba, Rb i Zn, które można również analizować za pomocą przenośnych spektrometrów pXRF. Wykonane porównanie wyników składu chemicznego uzyskiwanych przenośnym spektrometrem pXRF oraz w laboratorium Actlabs wykazało, że możliwe jest wykorzystanie na większą skalę samych pomiarów spektrometrem pXRF. Dla większości pierwiastków diagnostycznych uzyskano wystarczająco precyzyjne wyniki przy wykorzystaniu przenośnych spektrometrów pXRF.
EN
The article presents an attempt to conduct a chemostratigraphic analysis of the different-age rocks that form the Carpathian orogen. First, it was decided to create a synthetic geological profile for sediments occurring in the eastern part of the Polish Carpathians. The samples, mostly sandstones, were sourced from the primary stratigraphic layers in the Skole and Silesian Units, where rocks from the Lower Cretaceous to the Paleocene were identified. Due to the availability of research material, samples with well-documented stratigraphy were chosen from two wells, D-1 and H-1, with a particular focus on their stratigraphic classification. Subsequently, for comparison, a chemostratigraphic profile was generated for the Kuźmina-1 well. The analysis revealed significant disparities in chemical composition among the primary stratigraphic layers, which had been distinguished through paleontological studies in the examined boreholes. This made it possible to establish distinct boundaries between individual stratigraphic layers. The ability to create distinct chemostratigraphic models for the four examined stratigraphic horizons: Upper Cretaceous – Senonian (Inoceramian Beds), Upper Cretaceous/Paleocene (Istebnian Beds), Eocene (Variegated Shales), and Oligocene (Krosno Beds) was also confirmed through the creation of a Herrón classification diagram. The greatest variability of chemostratigraphic characteristics was observed in the Cretaceous formations. Initially, the tests were carried out in an accredited laboratory at ACTLABS, enabling the subsequent evaluation of results obtained using portable spectrometers (pXRF Titan, covering a measurement range from Mg to U, and pXRF Tracer, capable of also measuring Na content, both manufactured by Bruker). It was confirmed that clear variations in the content of individual elements were discernible for both major and trace elements. The most diagnostic elements include Na, Mg, Fe, K, Ca, and also Si, although the variability range is slightly narrower for the latter element. As for trace elements, these comprise S, P, Mn, Ti, Sr, Zr, Ba, Rb, and Zn, which can also be analyzed using portable pXRF spectrometers. A comparison between the chemical composition results obtained with the portable pXRF spectrometer and those from the ACTLABS laboratory revealed the feasibility of using pXRF measurements on a larger scale. For most diagnostic elements, sufficiently precise results were obtained using pXRF.
EN
The ALpine-CArpathian-PAnnonian (ALCAPA) block is one of the terranes involved in the Alpine-Tethys suture along with the North European Plate. In the Western Carpathians, this suture is supposed to be represented by the Pieniny Klippen Belt (PKB) which is a few kilometres wide and about 600 km long unit between the Outer Western Carpathians (OWC) and Central Western Carpathians (CWC) (Plašienka et al., 1997; Schmid et al., 2008). Unlike the Neotethian suture in the Western Carpathians, the PKB does not show the typical characteristics of a suture. The PKB is a sub-vertical unit with mainly shallow marine limestone and flysch deposits in a conspicuous “blockin-matrix” structure (Plašienka et al., 1997). The presence of “exotic” sediments in the PKB and the southernmost units of the OWC along with their shallow marine deposition environment led to the theory proposing the presence of a continental sliver called the Czorsztyn Ridge in the Alpine Tethys, dividing it into two oceanic/marine basins: the Magura Ocean to the north and the Vahic Ocean to the south (Plašienka, 2018). This controversial continental fragment possibly forming the basement for PKB successions, and its structural relationship with the adjoining OWC and CWC units, make it the main target of this project. The objective is to find evidence of the presence of this continental block, the Czorsztyn Ridge, which may have subducted along with the Vahic oceanic lithosphere underneath the CWC (Schmid et al., 2008). A passive seismic experiment will provide insight into the deep lithospheric structure across the PKP, testing the presence of a tectonic suture along with relaminated remnants of the Czorsztyn Ridge, and potential remnants of subducted or underthrusted lithosphere. Eighteen broadband stations have been deployed in a ~N-S transect (Fig. 1a) under the umbrella of the AdriaArray initiative, cutting across the PKB and Neotethian Meliata suture to the south. The data obtained during up to three years will complement 10 other permanent and temporary broadband stations, forming an approximate 370 km long profile and will be used to perform receiver function analysis and build structural and velocity models of the lithosphere (i.e., Schiffer, 2014; Schiffer et al., 2023) beneath the Western Carpathians. The horizontal extent of the imaging is shown in Figure 1b.
EN
There is a unique tectonostratigraphic unit called Kaminnyi Potik occur in the Ukrainian-Romanian Carpathian transborder zone. In the Ukrainian part numerous outcrops of this unit can be observed in many streams near Rachiv city, but its most spectacular occurrence is in the Chyvchyn Mountains. The whole complex consists of volcanogenic-sedimentary rocks and is divided into two Berriasian formations: Chyvchyn and Kaminnyi Potik. In the section of the Chyvchyn Formation, at the base, there are pillow lavas (basalts and andesites/trachyandesites) and volcano-sedimentary breccia with clasts of lava, coral limestones and radiolarites (submarine debris flows), and peperites as well. The Kaminnyi Potik Formation is made up of fine-grained hyaloclastic and carbonate debris flows of a flysch character (including organodetrital limestones with fragments of: corals, bryozoans, echinoderms bivalves and foraminifera), which overlying breccias and coral limestones of the Chyvchyn Formation. The profile ends by thin-bedded cherty limestones. The thin sections analysis revealed the following microfacies: oolithic-echinoderm packstone/grainstone; coral lithoclastic quartz packstone/grainstone; oolithic-lithoclastic wackestone/packstone; lithoclastic-echinoderm packestone; lithoclastic packestone; radiolarian echinoderm packestone; radiolarian wackestone; radiolarian-calpionellid wackestone and mudstone. Pyroclastic material is often present in the matrix. The ooids observed in the thin sections and the remains of fauna such as corals, echinoderms and bivalves suggest that the original material came from a carbonate platform that was sheltered by a coral reef. As a result of volcanic eruptions and possibly accompanying earthquakes, the platform has been destroyed and its traces are visible in clasts. Sedimentological character of submarine debris flows, (e.g. fractional graiding, mixture of shallow-water fauna and lithoclasts with deep-marine microfauna (radiolarians and calpionellids) and hyaloclastic material present in the matrix document short-term episodes of a catastrophic nature, leading to the redeposition of shallow-water sediments to the deeper parts of the basin.
EN
The Outer Banda and Carpathian arcs, of eastern Indonesia and Europe respectively, are examples of the highly arcuate fold-and thrust belts enclosing extensional basins that have been named oroclines. Both regions have experienced large scale extension within what is, overall, a compressive regime created by the convergence of major continental blocks and, despite major differences stemming from the quasi-oceanic setting of the one and intracontinental the setting of the other, there are reasons to suppose that comparative studies may produce insights into the evolution of both areas (Milsom, 2000). Processes in the Banda region are in some respects more open to direct examination, because extension is more recent, deep seismic activity is more widespread and basement structures are not concealed beneath thick sediment cover. To a considerable extent these advantages have compensated for the disadvantages of poor access and a relatively sparse database. The final two decades of the Twentieth Century saw rapid advances in understanding the area in terms of both geology and geophysics. In the first decade of the 20th century the techniques of seismic tomography began to be applied (Hall & Spakman, 2003) and confirmed the earlier interpretation, based on hypocentre locations, of the presence of a single, scoop-shaped, slab underlying the Banda Sea (Milsom, 2001). Intensive field and laboratory studies of Seram, the largest island in the northern part of the Outer Arc, then identified exposures of rocks metamorphosed at ultra-high temperature in the vicinity of the crust-mantle boundary, which led to the abandonment of the earlier interpretations of the associated ultramafic rocks as ophiolitic (Pownall et al., 2013). The extreme extension that brought these rocks to the surface also affected the subducted lithosphere that underlies the Banda Sea, and is one of the many pointers to the importance of asthenospheric flows in creating the present situation. While similar in many respects, the Carpathia-Pannonia area shows an orocline at a much later stage in its evolution, with some evidence concealed by later overprinting and some processes that would have been important in earlier stages now no longer occurring. On the other hand, some other aspects of orocline formation are likely to be better displayed there than in the Banda region. The now increasingly well determined history of the destruction of the Western Tethys and the development of the Alps-Carpathian-Dinarides orogen (e.g. Handy et al., 2015) offers strong support for theories involving mantle flow as a key factor in orocline formation.
EN
The Carpathians contain the remains of the Western Tethys, the main of which are: continental/microcontinental fragments (Alkapa and Tisza-Dacia terranes) of the Tethys Ocean, now located in the Central (Inner) Carpathians, and (palaeo)accretionary prisms, building mainly the Outer Carpathians. The Ukrainian Carpathians occupy the junction where the Western Carpathian and Eastern Carpathian nappe systems converged. In the presented work, author try to reconstruct the tectono-sedimentary evolution of the Eastern and Western Carpathian nappe systems in the junction area on the basis of own and published geomapping works, stratigraphic, sedimentological and structural research using existing restorations (see van Hinsbergen et al., 2020 and references therein). The Central Western Carpathian nappes (part of the Alcapa Terrane) are not exposed in Ukraine and probably buried under Neogene Transcarpathian Depression. The Central Eastern Carpathian nappes (part of the Tisza-Dacia Terraine) are represented in Ukraine by the Marmarosh thick-skinned basement nappes, that were formed in the Early Cretaceous time and overlapped by the latest Early Cretaceous–Paleogene post-nappe sedimentary cover. Between the Central Eastern and Central Western Carpathian nappe systems, the Pieniny Klippen Belt suture zone and Monastyrets Nappe filled with Paleogene flysch are developed. The structure of the junction between the Outer Eastern and Outer Western Carpathian nappe systems is more complicated. In Ukraine, the Outer Carpathians are made up of a several stacked nappes filled with Cretaceous–Neogene, mainly flysch sediments uprooted from their original substratum. In the Eastern Carpathian segment of Tethys at the Late Jurassic and/or Early Cretaceous, Ceahlau-Severin ocean (called Fore-Marmarosh one in Ukraine) was opened between the Dacia continental block (part of the Tisza-Dacia Terrane) and the Eurasian continent (van Hinsbergen et al., 2020 and references therein), that suggested by rift oceanic and continental basalts occurring under the Cretaceous flysch of the Outer Eastern Carpathian. Sinking of the Dacia (micro)continent into a subduction zone existed in the Neotethys ocean and inclined to the west (van Hinsbergen et al., 2020), could have caused the east-directed thrusting of the thick-skinned Marmarosh Nappes towards the CeahlauSeverin ocean. Ahead the Marmarosh nappe pile, the Eastern Carpathian Internal flysch thin-skinned nappes such as the Kamyanyi Potik, Rahiv, Burkut, Krasnoshora, Svydovets and Chornohora ones were formed. Coarsening upward and regular younging of the stratigraphic successions from inner to outer nappes suggest their attribution to the accretionary wedge growed in the Early Cretaceous–Paleogene time due to the subduction of the Outer Carpathian flysch basin basement under the Marmarosh pile. In the Western Carpathian segment, the Pieniny Klippen Belt accretionary wedge began to rise in the Late Cretaceous due to subduction of the Penninic oceanic domain under the Central Western Carpathians (part of the Alcapa Terrane) accompanied by detaching and grouping together originally very distant lithofacies (Plašienka, 2018 and references therein). The Western Carpathian Internal flysch nappes such as the Magura and Dukla units were attached to the Fore-Alcapa prism during the Middle Eocene–Oligocene, accordantly to outward shifting and uplifting of the trench-like Magura and Krosno lithofacies during this time. Closuring of the Monastyrets “between-terrainian” flysch basin at the late Eocene suggests the collision of the Alcapa and Tisza–Dacia terranes at the turn the Eocene and Oligocene. As a result, the Fore-Alcapa and Fore-Tisza-Dacia wedges were incorporated within an amalgamated internal wedge system that limited from the SW the Outer Carpathian basin. This unificated Menilite–Krosno basin was gradually uplifted and its deposits were subsequently thrusted as the external Silesian, Skyba and Boryslav-Pokyttya nappes onto the Miocene Carpathian Foredeep. Sedimentological and structural data suggest northeastward shift/migration of the wedge front–trench/foredeep– forebulge during Carpathian evolution. In addition, the junction of the Eastern and Western Carpathian accretionary wedges is complicated by strike-sleep movements.
EN
The northern part of the Carpathians covers the north-eastern area of the Western and north-western of the Eastern Carpathians. The basement of the Carpathians in this zone is of a transitional nature and is relatively poorly explored, which results from its deep burial, in particular under the so-called Outer Carpathians. The interpretation of the tectonics and geodynamics of the basement depends to a large extent on the analysis of large scale geophysical data. In this area, regional seismic surveys were carried out mainly using the so-called deep refraction and numerous geophysical works using gravity, magnetic, geomagnetic and magnetotelluric methods. The subject of the presented work is a review of the regional image of electromagnetic and gravity studies carried out in this area, with particular emphasis on the territory of Poland, within which the authors carried out numerous research works. Electromagnetic research allows for the construction of a regional model of basement resistivity distributions and the determination of general outlines of its geometry as well as the formulation or testing of the concept of its geodynamical interpretations. An auxiliary role in this aspect is played by gravity data allowing to recognize the density distribution of the basement and constituting a set of additional data for integrated interpretation. The area outside the territory of Poland was presented on the basis of literature data, creating an extensive regional background for the results of research related with the participation of the authors in Poland. Within the Polish Carpathians, there is a structural reconstruction of the Carpathian overthrust and its basement, as well as a clear change in the nature of geophysical fields, e.g. the system of gravity field anomalies. Due to the deep burial of the Carpathian overthrust in this area and the complex structure of the orogen, which hinder effective drilling penetration, its fragmentary and uncertain recognition is based mainly on geophysical surface studies. The complex structure of the orogen reduces the effectiveness of the use of the seismic reflection method, the participation of which is limited in practice to the recognition of the basement in the marginal zone of the Carpathian overthrust. In the remaining area, alternative methods of surface geophysics are used, i.e. the magnetotelluric and gravity method. An important role in recognizing the basement of the Eastern part of the Polish Carpathians was played by magnetotelluric soundings that cover the above mentioned area with a relatively dense network of several generations of measurement points. The results of the interpretation of the MT soundings were used to construct a resistivity model, which was verified by new results of regional processing of seismic data and magnetotelluric and gravity modelling. The visualization of resistivity distributions was presented through maps interpreted at selected depth levels and in the resistivity cross-sections form. Resistivity distributions are the basis for interpreting tectonic zones marked as resistivity contrasts. Forward modelling and inversion of gravity data were used to verify resistivity structural models.
EN
Quite common in publications devoted to the marine and lacustrine environments are differences of opinion on bathymetry of the basin receiving detrital sediment, especially when sedimentary structures are interpreted as indicators of specific depth-defined environments (following classic textbooks). However modern studies of deep-water environments, experimental work, modelling and numerous outcrop studies of ancient successions mitigate against such an approach. In this respect, the flysch succession of the Menilite Beds strata at Skrzydlna, which contains a variety of features that can confuse a cursory observer seems to serve as a universally applicable example. The succession at Skrzydlna records deposition in the western part of the synorogenic Dukla Basin during the Oligocene. The Menilite Beds are considered by most authors as deep marine deposits (the bathyal zone). The exposed section, almost 200-metre thick, is divided into three lithological intervals, each of which represents a radically different type of sedimentation. These are: i) a fine-grained association of terrigeonous and hemipelagic sediments; ii) infill of a canyon incised by about 40–50 m into the underlying strata, wider than outcrop and dominated by an olistostromal succession of debris flows with pebbles, boulders, slide and slump sheets; iii) succession of turbidites forming three fining-upwards sequences and ranging from thick, massive, amalgamated sandstones deposited by high-density flows in laterally migrating outcrop-scale channels, through ‘normal’ turbidites forming complete Bouma sequences (Ta-e), containing dunes and fining to Tce in the uppermost associations of thin-bedded sandstones and shales. These features suggest rapid uplift of the source area resulting in canyon incision and sudden onset of the olistostrome deposition that evolved upwards into proximal turbidite-fan sequence, which subsequently retrograded due to decreasing intensity of supply. The oldest interval (i) consists of predominantly finegrained facies, most characteristic of the Menilite Beds at their regional development. These are dark mudstones deposited in anoxic to dysoxic conditions and containing thin layers of fine-grained sandstones — turbidites with Bouma Tab; Tbc; Tabc; Tabe intervals, a 2–3 m thick intercalation of massive amalgamated sandstone, dark cherts, and locally silicified marls and limestones. The latter contain isolated lenses of medium-grained sandstone current ripple marks indicating three palaeocurrent directions. Two sets represent bipolar distribution of palaeocurrents, typical of shallow sea/ shelf sediments reworked by tidal currents. However, these are interpreted here as the products of tidal currents reworking bottom sediments of the bathyal zone, the case known from contemporary environments. In this context, the third direction, perpendicular to the bipolar flows does not represent reworking by littoral current on shelf but deep marine contour current. The main channel, or canyon (ii) incised into the slope sediments fed the depositional system with olistostrome deposits supplied from the rapidly uplifted source zone. Above there is a thinning upwards, turbidite sequence of four sub-complexes (A-D): A – conglomerate and sandstone fill three laterally migrating narrow, outcrop-scale erosional channels with a maximum depth of 15 m; B  – two shallow (up to 2 m deep) distributary channels filled with very thick, massive or normally graded sandstones; C  – turbidites Tb, Tc, Tbc with single occurrences of hummocky-like cross stratification and sandstone beds forming dunes at the mouth of distributary channels; D  – less ordered interval of thick-, medium- and thin-bedded sandstones interbedded with mudstones, forming various incomplete sequences of Bouma intervals. Interbeds of hummocky-like cross stratification, commonly found on the shelf, are interpreted in the deep-sea environment as the effect of Kelvin-Helmholtz instability or other complex flow processes, e.g. reflections of turbidity currents. A few occurrences of ripplemarks symmetrical in outer shape show unidirectional cross-lamination in cross section. These were modified by erosion that could have resulted from occasional extremely violent storms or flow reflections off channel margins. In spite of the external shape reminiscent of symmetrical ripplemarks these features do not possess the internal structure of composite cross laminae characteristic for oscillatory reworking of sand by prolonged, rhythmic action of waves. Solitary current ripplemarks showing flow directions opposite to the main transport direction are antidunes or deposits of currents reflected/deflected by channel sides. In summary, in spite of geometrical and structural similarity to the features traditionally considered as formed on shelf, the structures described here, assessed in association with facies and evidence referred to in the introductory paragraphs, fall into the category of deposits known also from below the ‘normal’ wave base and below the shelf edge, i.e. in the slope region. Hence from deep-sea environment for which the occurrence of bipolar currents, dunes, hummocky cross-stratification and symmetrical ripplemarks are neither typical nor diagnostic, but do exist.
EN
The surrounding of the Čoltovo village is a well-known location related to the Meliata Superunit (especially Meliata Unit s.s.). The Meliata Unit is represented by intricate mélange complexes linked to the closure of the ancient Meliata Ocean, as a significant part of the Western Carpathians geological story. In general, Meliata complexes are divided into HP/LT Permian to Jurassic metamorphosed clastic sediments, carbonates and basic volcanics (Bôrka Nappe) and complexes of “mixed chaos” of the Jurassic low grade shales with huge Triassic olistostrome bodies (Meliata Unit s.s.), the latter being the main subject of this work. Outcrops near the village of Čoltovo along the slopes of the W–E trend on the Slaná River bank provided limited information only. Therefore, new parts were excavated in March/2022. After removal of debris, the very complex internal structure of the mélange can be clearly detectable. This new section is composed of six individual outcrops (ČLP1 to ČLP6 from left to right) and consists of two contrasting lithological parts. The eastern part is mainly characterized by strongly weathered gray fine-grained shales and tuffs containing blocks of lithologically variable rocks. These are mainly represented by basic volcanics and dark coarse-grained Jurassic crinoidal limestones. The western part of the section consists of red and white fine-grained siliciclastics with basic volcanic material, and blocks of dark red, green and purple radiolarites. In the upper parts of the outcrops, layers of dark crinoidal limestones, shales and conglomerates of the Jurassic age are present. The connection between these beds and the mélange is documented by their presence as blocks in the left part of the section. The mélange complexes are overstepped by the Lower Miocene organodetritic limestones, sandstones and breccias (Bretka Beds). Three samples from the western part of the new outcrops gave identifiable Middle Triassic radiolarians. In addition, an old outcrop to the east of the newly excavated section, provided a productive sample with Upper Triassic radiolarian microfauna. Our research was also focused on geochemical analyses of radiolaria-bearing siliciclastics and basic volcanics, aiming at understanding the palaeoenvironment of the Meliata Ocean. All of the sediment samples gave similar results, which point to shallow marine environment, close to the continental margin. The geochemical data indicate a mature continental sedimentary provenance. Based on these data, we interpret the source of the samples located to the north of the Meliata Ocean (possibly Permian clastics of the Gemer Unit). Basic volcanics sample from the right side of the section confirms basalt/basaltic andesite composition. From the study of the Čoltovo section it seems the sedimentary matrix of the olistostrome probably originated from a passive continental margin and it is mixed with advanced ophiolite-bearing nappes within a Jurassic accretionary mélange (Meliata Unit s.s.).
EN
The palaeogeographic positions of the pre-Cretaceous Tethys “western ends” (Kovács, 1992) and their relationships to easterly located oceanic domains remain to belong to the most challenging issues in deciphering the structure and tectonic evolution of the European Alpides (e.g. Schmid et al., 2020). Due to the westward increasing paucity of direct indications of ancient oceanic domains and their discontinuous occurrences, a number of sometimes considerably different reconstructions have been proposed by several authors. All these are based on various data and authors’ preferences; therefore achievement of a widely accepted model seems not to be probable at present. In general, searching for evidences of former oceanic domains in the nappe edifice of collisional mountain belts, commonly in the suture zones, is based on several fundamental criteria: 1) ophiolite slivers and ophiolite-bearing mélanges as vestiges of consumed oceanic lithosphere; 2) blueschistto eclogite-facies metamorphosed units recording the subduction/exhumation processes within a subduction channel and/ or accretionary prism; 3) deep-marine synorogenic sedimentary complexes like wildflysch or olistostromes; 4) mixture of these in chaotic units within an accretionary wedge; and 5) a specific case of intraoceanic subduction resulting in ophiolite obduction, but this is not considered as a continental collisional tectonic setting. Indirectly, position of past oceanic basins can be detected by: a) secondary occurrences of an oceanic crust-derived detritus, including the heavy mineral spectra, in syn- to early post-orogenic sedimentary clastic formations and clues to their source areas; b) shelf-slope-continental rise facies polarity of former passive margins; c) progradational trend of collisional thrust stacking of the lower plate with a suture (often totally destroyed) in the uppermost structural position in the rear part of an orogenic pro-wedge; d) subduction-related calc-alkaline magmatism accompanying the active margin; e) upper plate back-arc extension, or retro-wedge thrusting opposite to the pro-wedge in a bivergent orogen with the suture in its axial zone; f) major crustal-scale discontinuities revealed by deep seismic sounding connected to surface fault zones separating palaeogeographically distinct domains indicating possible plate boundaries. All these potential clues have been considered while reconstructing the Mesozoic tectonic evolution of the Western Carpathians (Plašienka, 2018 and references therein). It should be noted that no single criterion characterized above, even not a few indirect signs are enough to define a particular orogenic zone or unit as an evidence for an oceanic suture. There is only one Western Carpathian zone which fulfils most of them. It is represented by units and rock complexes grouped in a tectonic superunit known as the Meliaticum and respective oceanic realm as the Meliata Ocean. The Meliata-related units bear clear signs of criteria 1, 2, 3, 4 and indirect indicators a, b, c and e. Whatever different are the interpretations of the Meliata Ocean origin (e.g. born as a back-arc basin initiated by the northward subduction of Palaeotethys, or simply as a northern margin or embayment of Neotethys), or even its existence as an independent domain (regarded as a facies zone only), all palaeotectonic interpretations of the Alpine tectonic evolution of the Western Carpathians have to take into account these pieces of evidence.
EN
The Carpathian Flysch Belt represents a Paleogene accretionary wedge (External Western Carpathians  – EWC) located in front of the narrow Pieniny Klippen Belt zone and the Cretaceous Central Western Carpathian nappe stack. The Flysch Belt is formed of several nappes thrust over the slope of the European Platform in the Miocene. This study is focused on the uppermost Magura Nappe, which consists of the Rača, Bystrica and Krynica subunits. As there are no relics of pre-Miocene oceanic crust in the EWC, the sedimentary rocks of the Flysch Belt are the only source of information available about the Alpine collisional events. U-Pb geochronology was applied to detrital rutile from sandstones of the Magura Nappe in order to better understand the closure of the Alpine Tethys in the Western Carpathians. Ten medium-sized sandstone samples were collected across the Bystrica and Krynica subunits in the Nowy Targ region in southern Poland. The samples represent synorogenic clastic sediments with inferred deposition ages between the Late Cretaceous and Oligocene. Approximately 200 rutile grains were separated from each sandstone sample and around half of them were selected for further analyses. The age and appearance (shape, inclusions, zoning etc.) of the dated rutile show significant variations, suggesting derivation from various sources. The most prominent age peaks represent the Variscan (c. 400–280 Ma) and Alpine (c. 160–90 Ma) tectonic events which are well-pronounced in all but the oldest dated sample. It is also noteworthy that four distinct Alpine signals were detected in our rutile data set. The two most prominent peaks with ages of 137–126 Ma and 115–105 Ma are found in majority of the samples. In two sandstone samples, deposited between the Eocene –Oligocene and the Late Cretaceous–Paleocene, the youngest peak of 94–90 Ma appears. Another peak of 193–184 Ma is also present in these two samples, as well as in another sandstone deposited between the Paleocene and the Eocene. In addition, most samples show few Proterozoic ages (approx. 1770 Ma, 1200 Ma, 680 Ma and 600 Ma). Since metamorphic rutile requires relatively high pressure to crystallize, its formation in the course of an orogeny is possible in a subduction setting. Hence, our new age data may reflect tectonic events related to subduction of oceanic crust and overlying sediments. Tentatively, we propose that recognizable events include the Jurassic subduction of the Meliata Ocean (~180–155 Ma), the Early Cretaceous thrust stacking of the Veporic and Gemeric domains (140–105 Ma) and possibly the Late Cretaceous subduction of the Váh Ocean (c. 90 Ma). In addition to dating, the Zr content of the rutile formed during the Alpine orogeny was measured by electron microprobe at the AGH University in Krakow. The amount of Zr varies between 37–420 ppm in almost all grains, with the exception of 4 rutile grains where ~1100 ppm was reached. The Zr in rutile thermometer, based on the approach of Kohn (2020) was used to calculate the possible metamorphic conditions at 450–650°C and >7.5 kbar. This data set corroborates formation of the Alpine rutile under relatively high pressure and rather low to moderate pressure/temperature gradient, i.e. typical of subduction-related tectonic environments.
EN
The evolutionary history of the Skole Basin during the Campanian–Paleocene period exhibits several cycles of progradational and retrogradational movement, accompanied by shifts from carbonate to siliciclastic-dominated sedimentation, which are recorded in the Ropianka Formation deposits (Kotlarczyk, 1978). These changes are primarily driven by fluctuations in relative sea levels and tectonic activity (Kotlarczyk, 1988; Kędzierski & Leszczyński, 2013). The study area is located south of Tarnów and encompasses western part of the Skole Nappe, the most external major tectonic unit in the Polish Outer Carpathians. Skole Nappe stands as a folded and thrust remnants of sedimentary infill of the Skole Basin, being one of a several deep-water basins located at the northern margin of the Tethys Ocean (Ślączka et al., 2012). The progradational-retrogradational cycles initiate with the appearance of sand-rich bodies at the lower part of the sedimentary log, which gradually diminish up the section. The depositional environment of the study area contains a broad range of distinguished submarine fan setting including channel-fill deposits, the transition zone between channels and lobes, and various sub-environments within depositional lobes such as the lobe axis, off-axis and lobe fringe, distal fringe, and interlobe areas. The intricate distribution of facies throughout the studied time interval can be attributed to the basin’s asymmetry, characterized by a steep southern slope and a gentler northern slope, as well as the influence of multiple sediment sources. The significant aggradation of specific depositional elements, variations in calcareous sediment content, and changes in palaeotransport directions indicate the presence of morphological obstacles and/or the semi-confined nature of the Skole Basin in the study area. Further field investigations have identified two distinct submarine depositional settings characterized by sediment bypass: channel-lobe-transition zone and marl-dominated lower slope or base-of-slope bypass zone. Despite domination of marls, the second type of bypass zone tends to show two different end-member variants. The first type involves a higher proportion of thin- and thick-bedded coarse-grained lag deposits, while the second type consists of dune scale bedforms with intraformational. Log with more intermediate characteristics occurs as well, reflecting the spatial continuum of facies changes in the marl-dominated bypass zone and transition to the marl-dominated lower slope and base-ofslope deposits. Record of intervals with siliciclastic sediment bypass within areas of predominantly marly deposition can serve as valuable indicators of turbidite system progradation despite relative sea-level highstand connected with carbonate production. Moreover, such deposits may indicate smallscale sea-level changes or tectonic pulses within deep-water monotonous sedimentary successions predominantly composed of fine-grained sedimentation.
EN
The scope of this analysis included fluvial sediments of the low terrace of the Grajcarek stream in the Małe Pieniny Mts. (Western Carpathians). The structure of the terrace has been surveyed in five profiles. The sedimentary sequence includes alternating layers of gravel and calcareous mud with a maximum thickness of up to 2.2 m. A rich and varied malacofauna has been found in the mud. The age of the sediments was determined using the radiocarbon method. The sediments that make up the terrace cover the younger part of the Middle Holocene and the entire Late Holocene. The analysis of the malacofauna has allowed for the characterization of environmental changes. The most important of them dates back to the Middle Ages and is associated with the phase of intensive settlement in the Pieniny Mts.. It is indicated by deforestation and the related change in the composition and structure of malacocoenoses manifested by the replacement of forest communities by ones with open-country species. Gravel horizons are records of flood periods correlated with wet climatic phases. It is possible to distinguish six such phases covering the following periods: 6600–6100 y cal BP, 5500–5100 y cal BP, 4500–4100 y cal BP, 3200–2300 y cal BP, 2000–900 y cal BP and 400–200 y cal BP. They correspond to the periods of increased fluvial activity of rivers, intensification of mass movements, advances of alpine glaciers and the increase in the water level in lakes.
PL
Analizy mikroskopowe materii organicznej mają kluczowe znaczenie w analizie systemów naftowych i poszukiwaniach złóż węglowodorów. Informacje o składzie macerałowym oraz stopniu zaawansowania przemian termicznych są nieodzowne w typowaniu perspektywicznych rejonów poszukiwawczych, modelowaniu procesów generacji oraz we wszelkiego typu aspektach geologicznych, w których skały macierzyste pełnią priorytetową rolę. Przeanalizowano skład macerałowy i dojrzałość rozproszonej materii organicznej w wybranych wydzieleniach litostratygraficznych jednostki dukielskiej. Materiał badawczy stanowiło 50 próbek, pobranych z 23 odsłonięć. Próbki pochodziły z warstw inoceramowych, hieroglifowych, menilitowych i krośnieńskich oraz z łupków pstrych i warstw z Majdanu. Zasadnicza część badań obejmowała obserwacje mikroskopowe w świetle odbitym i UV, a także pomiary refleksyjności witrynitu. W celu pełniejszej interpretacji, w przypadku części próbek wykonano pirolizę Rock-Eval. Skład materii organicznej pod kątem jakościowym wydaje się zbliżony – najczęściej obserwuje się zarówno macerały z grupy witrynitu, jak i liptynitu i inertynitu. Ewentualne różnice uwypuklają się w proporcjach pomiędzy udziałem macerałów z tych grup. W obrębie grupy witrynitu wyróżniono większe fragmenty kolotelinitu (>10 µm) oraz mniejsze witrodetrynitu (<10 µm). Grupa macerałów liptynitu zdominowana jest przez alginit, rzadziej natomiast obserwuje się bituminit, liptodetrynit, sporynit i kutynit. Macerały z grupy inertynitu to najczęściej pokruszone fragmenty semifuzynitu oraz fuzynitu oraz drobniejszy inertodetrynit. Dodatkowo w pojedynczych próbkach obecne są stałe bituminy, czasem mogące wykazywać zjawisko fluorescencji. Udział materii organicznej (parametr TOC) jest bardzo zróżnicowany – od <1% do 9%. Ze względu na zasobność w materię organiczną przebadane skały podzielono na skały o niskim (łupki pstre, warstwy z Majdanu, warstwy hieroglifowe), średnim (warstwy inoceramowe), wysokim (warstwy menilitowe) i zmiennym (warstwy krośnieńskie) TOC. Przebadane próbki wykazują również zróżnicowanie w proporcjach grup macerałów, charakteryzując się zarówno dominacją materiału witrynitowo-inertynitowego (warstwy inoceramowe i warstwy z Majdanu), jak też materiału witrynitowego (warstwy hieroglifowe), a także liptynitowego lub witrynitowoliptynitowego (warstwy menilitowe). Przebadana materia organiczna znajduje się na różnym stopniu przeobrażeń termicznych – od fazy niedojrzałej po późne „okno ropne”. Wydaje się, że w ujęciu regionalnym stopień dojrzałości rośnie w kierunku południowym i południowowschodnim.
EN
Microscopic investigations of organic matter play a key role in analyzing oil systems and prospecting for hydrocarbon fields. Information about its maceral composition and the degree of thermal transformations is essential in selecting prospective exploration areas, modelling generation processes and in all types of geological aspects where source rocks play a priority role. Maceral composition and maturity of dispersed organic matter in selected lithostratigraphic divisions of the Dukla Unit were analyzed. The research material consisted of 50 samples collected from 23 outcrops. The samples were collected from Inoceramian, Majdan, Hieroglyphic, Menilite and Krosno Beds, as well as from Variegated Shales. The main part of the research included microscopic observations under reflected light and UV as well as measurements of vitrinite reflectance. For a more complete interpretation, Rock-Eval pyrolysis was performed for some of the samples. In terms of quality, the composition of organic matter seems to be similar – macerals from the vitrinite, liptinite and inertinite groups are observed. Possible differences are emphasized in the proportions between the content of macerals from these groups. Within the vitrinite group, fragments of larger (> 10 µm) collotelinite and smaller (<10 µm) vitrodetrinite can be distinguished. The group of liptinite macerals is dominated by alginite, while bituminite, liptodetrinite, sporinite and cutinite are observed less frequently. Macerals from the inertinite group are most often represented by crushed fragments of semifusinite and fusinite, and finer inertodetrinite. Additionally, solid bitumens, sometimes exhibiting fluorescence, are present in individual samples. The content of organic matter (TOC parameter) is very diverse – ranging from <1% to 9%. Due to the content of organic matter, the studied rocks were divided into groups of low (Variegated Shales, Majdan Beds, Hieroglyphic Beds), medium (Inoceramian Beds), high (Menilite Beds) and variable (Krosno Beds) TOC. The investigated samples also show variability in the proportions of maceral groups. The dominance of vitrinite-inertinite (Inoceramian Beds and Majdan Beds), as well as vitrinite (Hieroglyphic Beds), liptinite and vitrinite-liptinite macerals (Menilite Beds) is observed. Investigated organic matter also varies in the degree of thermal transformations, from the immature phase to the late “oil window”. In regional scale, samples maturity appears to be increasing towards S and SE.
EN
The aim of the paper is to examine the variability of physical and chemical characteristics of two springs located in the Zagórzański Stream catchment (Spisko-Gubałowskie Foothills, Podhale region). Calcareous tufa occurs at one of the investigated springs. Field studies were conducted once a month from 25th March 2017 to 28thFebruary 2018. Water of the studied springs represents the bicarbonate-calcium-magnesium type during almost the whole year. The chemical composition of both springs is characterized by seasonal variability. The highest concentrations of most ions occurred in the summer, when the rainfall was the lowest and during winter drought; while the lowest concentration - in the period of increased rainfall. The variability of physical and chemical parameters of the spring with tufa is smaller than the other one. The spring with calcareous tufa stands out by the higher concentration of Mg2+ and SO42- and the presence of radon. The unique landscape values of the surroundings and hydrogeochemical features of the spring with calcareous tufa favour this place as an interesting hydro-tourism attraction in the Bukowina Tatrzańska region.
EN
Fluid and solid inclusions were analyzed in minerals of Carpathian rock samples from the Rabe vicinity by means of microthermometry and Raman spectrometry. Fluid inclusions are present in calcite and quartz that often co-occurwith organic matter in different spatial relationships. In case of the studied Ra 5 sample they fill a cavern in the mélange zone in the Carpathian flysch. The temperatures obtained from the combined research (FI 178.9186°C; Raman 178-205°C) give an insight into the geological history of that fragment of the Carpathians.
EN
In Butkov Quarry, ammonites of the families Holcodiscidae Spath, 1923 and Barremitidae Breskovski, 1977 occur in the pelagic Lower Cretaceous pelagic deposits of the Manín Unit. This contribution discusses the taxonomy of both families and presents their distribution in the layered sequences of the quarry. The genus Spitidiscus Kilian, 1910 classified as a member of the Superfamily Perisphinctoidea Steinmann in Steinmann and Döderlein, 1890 is an important representative of the Holcodiscidae from a stratigraphic point of view. In areas where the zonal index Acanthodiscus radiatus (Bruguière, 1789) does not occur, as in Butkov Quarry, the first representatives of Spitidiscus indicate the base of the Hauterivian. The genus Plesiospitidiscus Breistroffer, 1947 was long regarded as a member of the Superfamily Desmoceratoidea Zittel, 1895. This superfamily was based on its type species, Eodesmoceras celestini (Pictet and Campiche, 1860), which is not Valanginian in age, as now clearly proven. As a consequence, this superfamily is considered invalid. Vermeulen and Lahondère (2011) proposed an alternative by selecting a suitable initial genus, namely Plesiospitidiscus, for the Family Barremitidae, Superfamily Barremitoidea Breskovski, 1977 (nom. transl. Vermeulen and Lahondère, 2011).
EN
In July 2001, in the Carpathian basin of the Vistula, there was a lot of rainfall and storms. The meteorological situation of that time was similar to that of 1934 when a great flood occurred. On 25 July (2001st), in the upper part of the Skawa catchment, a violent storm occurred. Its centre was located right at Makowska Góra. The daily precipitation in Maków Podhalański was 190.8 mm that day. Most of the precipitation occurred during a storm. Although the precipitation was much lower in the other stations located in the drainage basin, the flow of the Skawa in Sucha Beskidzka was 660 m3 s-1, while the constructed dam in Świnna-Poręba – 1019 m3 s-1. Precipitation was so abundant that the floodplains terraces of the Skawa have been inundated, and made the streams flowing down the Makowska Mountain spill out of the trough. The centre of Maków Podhalański and the neighbouring streets were destroyed. The main current flowed through the streets of Źródlana, Krótka, Kościelna, Rynek, and Wolności. The biggest losses were caused by the Księży Potok and several smaller streams (Rzyczki, Grabce, and Czarny Potok) that poured out of the trough and flowed through them. The biggest losses have been incurred by the Budzów and Zembrzyce municipalities located on the other side of the mountain. The losses were caused by a small Paleczka stream.
EN
The presence in wood of saprotrophic fungi is crucial for xylophagous insects, as they modify its chemical composition, moisture content and structure, and thus govern the survival and growth rate of larvae. Little is known about the mycobiota colonising the breeding material of saproxylic species. This paper focuses on the mycobiota of dead wych elms Ulmus glabra as breeding material for the endangered Rosalia alpina. Fungal isolates from wood fragments of the breeding material were identified using molecular techniques. A total of 24 taxa of wood-decay fungi were found (16 Ascomycota, 6 Basidiomycota, 1 Zygomycota, 1 unidentified) – saprotrophs and facultative parasites, saprotrophic fungi, fungal parasites and tree parasites. Six taxa were isolated from both the surface and deeper layers of the wood, and also from the wood dust and frass left in R. alpina foraging sites: Cladosporium cladosporioides, Cladosporium sp., Hypoxylon macrocarpum, Phaeoacremonium fraxinopennsylvanicum, Sistotrema brinkmannii and Stereum hirsutum. These fungi may be crucial in enabling R. alpina to colonise dead or dying trees and affect its larval development. Ph. fraxinopennsylvanicum, H. macrocarpum and Daldinia childiae are reported for the first time from Poland.
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