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Episkeletobionts of large rugose corals from the Middle Devonian mesophotic palaeoenvironment recorded in the Pokrzywianka Beds (Holy Cross Mountains, Poland)

Zatoń Michał, Malec Jan, Wrzołek Tomasz, Kubiszyn Beata, Zapalski Mikołaj K.

Annales Societatis Geologorum Poloniae

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2022

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Vol. 92, No. 4

465--484

EN

Organisms encrusting corals from a coral horizon encountered in a trench in the Middle Devonian (Givetian) Pokrzywianka Beds of the classic Grzegorzowice-Skały section in the Holy Cross Mountains, Poland, are described and analyzed in the context of their palaeoecological and palaeoenvironmental background. These episkeletobionts form rather a low-diversity community, dominated by microconchid tubeworms, crinoids, and tabulate corals. The last group, however, is especially diverse at the family level, represented by auloporids, alveolitids, coenitids and favositids. These episkeletobionts are considered to have developed in a low-light, lower mesophotic palaeoeonvironment, as evidenced by the presence of platy, alveolitid tabulate coral in the deposits studied. This microconchid-crinoid-tabulate-coral community differs from other Givetian communities from the Holy Cross Mountains (Laskowa and Miłoszów), which also are considered to have developed in low-light habitats. The differences in taxonomic composition of episkeletobionts between these three localities most probably resulted from specific local conditions, related to bathymetry (light levels, nutrient levels), the specific nature of the hosts/substrates occupied, and also differences in larval dispersal patterns. This, in turn, shows that various encrusting communities may have inhabited seemingly similar, marine habitats within a given time interval and neighbouring areas, which may have serious implications for large-scale comparisons of biodiversity within a given palaeoenvironment.

2

Wyniki interpretacji strukturalnej utworów triasu i paleozoiku przedgórza Karpat opartej na nowych danych sejsmicznych

Urbaniec Andrzej, Bartoń Robert, Bajewski Łukasz, Wilk Aleksander

Nafta-Gaz

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2020

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R. 76, nr 9

559--568

PL

Głównym celem artykułu jest odtworzenie szczegółów budowy strukturalnej utworów triasu i paleozoiku centralnej części przedgórza Karpat na podstawie interpretacji nowych materiałów sejsmicznych 3D. W ramach interpretacji wykonano analizę atrybutów sejsmicznych, wśród których najbardziej pomocne były: Time gain, Relative acoustic impedance, First derivative, Dominant frequency oraz Instantaneous bandwidth. Dotychczasowe informacje na temat budowy geologicznej kompleksu paleozoicznego w tym obszarze pochodziły głównie z interpretacji profili sejsmicznych 2D, koncepcji regionalnych oraz informacji z jedynego głębokiego otworu wiertniczego zrealizowanego na przełomie lat 50. i 60. XX wieku. Wyniki przeprowadzonej analizy obrazu sejsmicznego wskazują, że podłoże jury zbudowane jest z szeregu bloków tektonicznych o zróżnicowanej wielkości oddzielonych powierzchniami dyslokacji. W większości mają one charakter bloków wychylonych (tilted blocks), stanowiąc pozostałość kaledońsko-waryscyjskiego systemu tektonicznego. Utwory paleozoiczne o wyraźnie uporządkowanych ciągłych refleksach sejsmicznych silnie kontrastują w obrazie sejsmicznym z zalegającym poniżej kompleksem anchimetamorficznych skał najwyższego ediakaru o nieuporządkowanym, jednorodnym zapisie. Klastyczne utwory dolnego triasu w pierwszej kolejności wypełniają głębsze partie półrowów tektonicznych. Na podstawie analizy obrazu sejsmicznego kompleks ten podzielono na dwie serie: dolną, o zdecydowanie mniejszych wartościach amplitudy i zauważalnie mniejszej ciągłości refleksów sejsmicznych, oraz górną, o zróżnicowanej dynamice i większej ciągłości refleksów. Najwyższym analizowanym kompleksem są węglanowe utwory retu i wapienia muszlowego, cechujące się wysokimi wartościami amplitudy i dużą ciągłością refleksów, dzięki czemu są one łatwo identyfikowalne na sekcjach sejsmicznych. Przeprowadzona analiza z wykorzystaniem atrybutów sejsmicznych pozwoliła na określenie charakterystyki sejsmicznej poszczególnych kompleksów litostratygraficznych triasu i paleozoiku oraz wniosła bardziej szczegółowe informacje o budowie geologicznej obszaru badań.

EN

The main purpose of the article was to reconstruct the structural details of the Triassic and Palaeozoic formations of the central part of the Carpathian Foreland based on interpretation of new 3D seismic data. The interpretation included the analysis of seismic attributes, among them Time Gain, Relative acoustic impedance, First derivative, Dominant frequency and Instantaneous bandwidth were the most useful. Previous knowledge on the geological structure of the Palaeozoic complex in this area was derived mainly from the interpretation of 2D seismic sections, regional concepts and data from the only deep well drilled in the late 1950s and early 1960s. The results of the seismic image analysis show that the Jurassic sub-surface is composed of a number of tectonic blocks of various sizes, separated by dislocation zones. Most of them are tilted blocks which are the remnants of the Caledonian-Variscan tectonic system. Palaeozoic sediments with clearly arranged continuous seismic reflectors strongly contrast in the seismic image with the complex of anchimetamorphic rocks of the uppermost Ediacaran characterized by disarranged, homogeneous record. Clastic formations of the Lower Triassic fill primarily the deeper parts of the tectonic half-grabens. Based on the seismic image analysis, the complex is divided into two series: the lower one, with significantly lower amplitude values and noticeably lower continuity of seismic reflectors and the upper one with diversified dynamics and greater continuity of reflectors. The highest analyzed complex is the carbonate formation of Roetian and Muschelkalk, characterized by high amplitude values and high continuity of reflectors so that it can be easily identified on seismic sections. The analysis carried out with the use of seismic attributes allowed to determine the seismic characteristics of individual lithostratigraphic complexes of the Triassic and Palaeozoic formations and provided more detailed information on the geological structure of the research area.

3

Thermal history of Lower Palaeozoic rocks from the East European Platform margin of Poland based on K-Ar age dating and illite-smectite palaeothermometry - 481 – 509

Kowalska Sylwia, Wójtowicz Artur, Hałas Stanisław, Wemmer Klaus, Mikołajewski Zbigniew, Buniak Arkadiusz

Annales Societatis Geologorum Poloniae

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2019

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Vol. 89, No. 4

481--509

EN

Large-scale shale gas prospecting in the Polish part of the East European Platform did not discover large reserves of this resources. The article presents new research indicating that one of the reasons for the lack of shale gas relates to the thermal history of the Lower Palaeozoic rocks. Illite-smectite palaeothermometry was used to reconstruct the history of the platform and determine the maximum temperatures to which these rocks were subjected. The age of illitisation was also constrained using the K-Ar method. This method allowed precise dating of the maximum age of thermal transformations due to the deposition of numerous pyroclastic horizons (K-bentonite) throughout the entire geological profile from the Cambrian to the Silurian. Isotopic dating was made on over 53 samples of Lower Palaeozoic bentonites and low-grade metamorphic clays. These results were supplemented by analysis of the degree of thermal (smectite to illite) transformation in the profiles of 37 deep boreholes. 11 zones could be distinguished with different tectonic histories within the Polish part of the East European Platform edge. Maximum heating occurred in this region at about 320–340 Ma, corresponding to the Early Carboniferous or the turn of the Early and Late Carboniferous, phase A of the Variscan orogeny, known as the Sudetian phase. In the southern part of study area, the maximum of thermodiagenesis is slightly younger – 270–290 Ma, which responds to the Early Permian, the Asturian phase, the last phase of the Variscan orogeny. This means that the generation of hydrocarbons occurred before significant Mesozoic exhumation of the Polish part of the East European Platform, which led to the escape of a considerable amount of the gas generated. The study also presents the results of an interlaboratory comparison of illite age dating using the K-Ar and Ar-Ar methods. The comparison was conducted to find out what realistic error should be considered when interpreting geological K-Ar dating results.

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Seismo-geological model of the Baltic Basin (Poland)

Kasperska Monika, Marzec Paweł, Pietsch Kaja, Golonka Jan

Annales Societatis Geologorum Poloniae

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2019

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Vol. 89, No. 2

195--213

EN

The aim of this study is to construct a seismo-geological model of the western part of the Baltic Syneclise. This model enables reconstruction of the tectonic processes taking place in this area, which had a significant impact on the formation of prospective zones for the occurrence of unconventional hydrocarbon accumulations. The two seismic surveys Opalino 3D and Kościerzyna-Gdańsk 2D, together with borehole data available in the vicinity, were used for the research. Well data were used not only for the seismic-to-well tie, but also for the construction of well cross-sections (including balanced ones). The structural interpretation of seismic boundaries enabled the separation of four structural stages: Precambrian; Caledonian, Permian-Mesozoic and Cenozoic. The seismic interpretation of the Opalino 3D survey indicates the presence of block-style tectonics in this area. This system is considered to be a part of a large block system, also extending throughout the area of the 2D survey. The Caledonian interval shows the greatest degree of structural complexity. Most of the large Palaeozoic dislocations already had been formed in the Cambrian. They underwent reactivation and/or inversion in the Silurian, or in the final stages of the Caledonian and/or Variscan Orogeny, at the latest. The current shape and structure of the Baltic Syneclise and the development of the Palaeozoic sedimentary cover were significantly influenced by the processes taking place in the Teisseyre-Tornquist Zone (TTZ). The dislocations of the Lower Palaeozoic stage are characterized by general NW-SE and NE-SW trends, although the first of these seems to be dominant.

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Palaeozoic palaeogeography of the East European Craton (Poland) in the framework of global plate tectonics

Golonka Jan, Porębski Szczepan J., Barmuta Jan, Papiernik Jan, Bębenek Sławomir, Barmuta Maria, Botor Mariusz, Pietsch Kaja, Słomka Tadeusz

Annales Societatis Geologorum Poloniae

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2019

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Vol. 89, No. 4

381--403

EN

Global palaeogeographic maps were constructed for eight time intervals in the Palaeozoic. The maps contain information concerning plate tectonics and palaeoenvironment during the Cambrian, Ordovician, Silurian, Devonian and Carboniferous. The East European Craton belonged to the Palaeozoic Baltica Plate, which originated as a result of disintegration of the supercontinent Pannotia during the early Cambrian. Baltica included part of Poland and adjacent areas northeast of a line that extends between Scania and the Black Sea. This plate was located in the Southern Hemisphere and drifted northward during Early Palaeozoic time. The Early Ordovician was the time of maximum dispersion of continents during the Palaeozoic. Avalonia probably started to drift away from Gondwana and moved towards Baltica during Ordovician time. Between Gondwana, Baltica, Avalonia and Laurentia, a large longitudinal oceanic unit, known as the Rheic Ocean, was formed. Avalonia was probably sutured to Baltica by the end of the Ordovician or in the Early Silurian. This process was dominated by the strike-slip suturing of the two continents, rather than a full-scale continent-continent collision. Silurian was a time of Caledonian orogeny, closing of the Early Palaeozoic oceans, collision of Baltica with Avalonia and Laurentia and the assembly of the supercontinent Laurussia. The Variscan orogeny in Poland was caused by the collision of the Bohemian Massif plates and the Protocarpathian terrane with Laurussia. The Protocarpathian terrane acted as an indentor that caused thrust tectonics in the East European Platform, Holy Cross Mountains and the Lublin area.

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Burial and thermal history of the Lower Palaeozoic petroleum source rocks at the SW margin of the East European Craton (Poland)

Botor Dariusz, Golonka Jan, Anczkiewicz Anneta A., Dunkl István, Papiernik Bartosz, Zając Justyna, Guzy Piotr

Annales Societatis Geologorum Poloniae

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2019

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Vol. 89, No. 2

121--152

EN

Thermal maturity modelling was carried out in over sixty wells along the SW margin of the East European Craton (EEC). The burial and thermal history modelling of the EEC, using thermochronological data, allowed the construction of burial history maps showing its geological development in the Phanerozoic. These results have proved that the Ordovician and Silurian source rocks occurring at the SW margin of the EEC reached a maximum palaeotemperature in the Palaeozoic, mainly during Devonian-Carboniferous time and at the latest during the Silurian in the most westerly part of this margin, along the Teisseyre-Tornquist Zone. In Mesozoic and Cainozoic time, the Ordovician and Silurian strata generally were subjected to cooling or to very minor heating, certainly below the Variscan level. The maximum burial and maximum temperature of the Ediacaran-Lower Palaeozoic strata were reached during the Early Carboniferous in the Baltic Basin and during the Late Carboniferous in the Lublin area, and even in the Early Permian in the SE corner of the Lublin Basin. Thus, the main period of maturation of organic matter and hydrocarbon generation in the Ordovician and Silurian source rocks was in the Late Palaeozoic (mainly Devonian-Carboniferous) and in the westernmost zone along the Teisseyre-Tornquist line at the end of the Silurian.

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Petroleum processes in the Palaeozoic - Mesozoic strata of the Grobla-Limanowa area (basement of the Polish Carpathians)

Wróbel M., Kosakowski P., Więcław D.

Geology, Geophysics and Environment

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2016

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Vol. 42, no. 2

185--206

EN

The geochemical characteristics of the Palaeozoic and Mesozoic strata of the basement of the Carpathian Foredeep depicted the Devonian and Carboniferous source rocks as the best source for hydrocarbon generation. Moreover, the Outer Carpathian sequence was geochemically characterized and proved capable of generating hydrocarbons. The oil-source rocks’ correlations indicated that the source of the condensate accumulated in the Łąkta field, while oil in the Grobla field. Maturity modelling identified Devonian source rocks as they reached a late phase of the “oil window” and, locally, even the “gas window”. The Carboniferous source rock was mature enough to start the generation processes. The generation started in the late Carboniferous, both in the Upper Silesian and Małopolska blocks. The main phase of the petroleum processes took place in late Neogene. The expulsion was observed only in the Devonian source rocks, and vertical migration by fault system in both blocks resulted in oil and gas accumulation in the Upper Jurassic carbonates and Upper Cretaceous sandstones. The petroleum modelling indicated the Devonian source for oil and gas fields in the study area. However oil-source rock correlation also suggests the presence of the Carpathian flysch source for hydrocarbons accumulated in the Łąkta field.

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Reservoir properties of the Palaeozoic–Mesozoic sedimentary cover in the Kraków–Lubaczów area (SE Poland)

Kosakowski P., Leśniak G., Krawiec J.

Annales Societatis Geologorum Poloniae

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2012

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Vol. 82, No. 1

51-–64

EN

During the 50-year-long intense petroleum exploration of the Palaeozoic–Mesozoic basement of the Carpathian Foredeep, more than 20 oil and gas accumulations have been discovered. The basic and most important oil-bearing levels in the Mesozoic section are Oxfordian carbonates and Cenomanian sandstones. The Nosówka, Zalesie, Trzebownisko–Krasne, Cetynia, Uszkowce and Lachowice hydrocarbon accumulations and numerous hydrocarbon shows have been found in the Palaeozoic horizons. This paper is focused on evaluation of reservoir properties of the entire Palaeozoic–Mesozoic basement of the Carpathian Foredeep and marginal part of the Outer Carpathians for finding new reservoir horizons. 558 rock samples from 51 wells in the Kraków–Lubaczów area were analysed. The well log results from 20 wells were additionally used for the assessment of petrophysical properties. The results of porosimetry measurements and well logs varied in all discussed Palaeozoic and Meso- zoic basement horizons of the Carpathian Foredeep. The best reservoir properties were estimated within the Jurassic–Lower Cretaceous carbonate complex. Despite great variability, the carbonate rocks display highest average porosity and good permeability values. The variability of reservoir properties is mostly a result of the character of the reservoir-porous-fracture space. Good reservoir properties were also estimated for the Upper Cretaceous carbonate rocks. However, in most of the analysed wells the potential reservoirs were watered. The Palaeozoic complex displays weaker reservoir properties and they mainly refer only to the Devonian–Lower Carboniferous horizon. The Lower Palaeozoic rocks display weak reservoir properties. Their potential is additio- nally lowered by negligible range of occurrence and a small thickness. Generally, the gas- and oil-bearing pro- perties of the analysed zone can be attributed only to the Jurassic–Cretaceous reservoir horizons. The remaining horizons, especially the Upper Palaeozoic complex, are only supplement to the reservoir potential of the area.

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Petroleum processes in the Palaeozoic and Mesozoic strata between Tarnów and Rzeszów (SE Poland) : 2-D modelling approach

Wróbel M., Kosakowski P., Krzywiec P.

Annales Societatis Geologorum Poloniae

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2012

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Vol. 82, No. 1

81–-97

EN

Two-dimensional modelling of hydrocarbon generation, expulsion, migration and accumulation pro- cesses in SE Poland between Tarnów and Rzeszów was carried out for five source rock horizons, i.e. the Ordo- vician, Silurian, Middle Devonian–Lower Carboniferous carbonates, Lower Carboniferous clastics, and Middle Jurassic. Five cross-sections in the study area allowed the reconstruction of timing and range of petroleum processes. The best source rocks related to the Ordovician and Silurian shales and mudstones reached “oil window” maturity within the entire study area and locally also reached the “gas window”. Generation of hydro- carbons was observed from all five source rocks, but the Ordovician and Silurian source rocks generated two and three times more hydrocarbons than the Lower Carboniferous and Jurassic source rocks, respectively. Expulsion took place only in case of the Lower Palaeozoic source rocks, but the volume of expelled hydrocarbons differed across the area. Hydrocarbons migrated from the Ordovician and Silurian source rocks to the Upper Jurassic (carbonates) and Upper Cretaceous (sandstones) reservoirs or to the Upper Palaeozoic carbonates in connection with the emplacement of the Carpathian thrust belt during the Miocene. Faults formed main migration pathways and hydrocarbons accumulated in structural and stratigraphic traps, located in the vicinity of faults. In places, traps are associated with a deep Miocene erosion surface. The onset of hydrocarbon generation took place during the Neogene, mainly the Miocene, but in the north, generation and expulsion started earlier – at the end of the Mesozoic.

10

Petrophysical properties of the pre-Miocene rocks of the Outer Zone of the Ukrainian Carpathian Foredeep

Kurovets I., Prytulka H., Shyra A., Shuflyak Y., Peryt T. M.

Annales Societatis Geologorum Poloniae

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2011

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Vol. 81, No 3

363-373

EN

The paper summarizes the results of various laboratory studies of core material, including porosity, permeability, lithological-facies and structural and textural characteristics of more than 1,000 samples of Mesozoic and Palaeozoic rocks. The petrophysical parameters of siliciclastic and carbonate rocks are analysed for the total of samples representing different lithologies (limestones vs. sandstones) as well as for particular stratigraphic intervals (Upper and Lower Cretaceous, Upper Jurassic, Middle and Lower Jurassic, and Palaeozoic). The terrigenous rocks with intergranular porosity and fracture-cavernous carbonate rocks of reefal facies form the best reservoir rocks within the Mesozoic. The terrigenous rocks of fractured and fractured-porous type that are controlled by the fault-block tectonics provide the best Palaeozoic and Ediacaran reservoirs.

11

Zarys budowy i ewolucji tektonicznej waryscyjskiej struktury Sudetów

Mazur S., Aleksandrowski P., Szczepiński J.

Przegląd Geologiczny

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2010

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Vol. 58, nr 2

133-145

EN

The structure and evolution of the Polish part of the Sudetes is reviewed on the basis of published data and interpretations. The Sudetic segment of the Variscides and its adjacent areas were subjected to multi-stage accretion during successive collisional events that followed closure of different segments of the Rheic Ocean. Early Variscan deformations culminated in the Late Devonian due to docking of the Armorican terrane assemblage to the southern margin of Laurussia. The Variscan orogenic activity continued into the Carboniferous and was associated with a new collision and intense folding and thrusting, followed by abundant magmatism, gravitational collapse and resulting exhumation of deeply buried metamorphic complexes as well as by inversion of the foreland basin. In the Sudetes, Variscan tectonostratigraphic units are tectonically juxtaposed and often bear record of contrasting exhumation/cooling paths, constrained by palaeontological and geochronological data. This provides evidence for the presence of allochthonous units, of partly cryptic tectonic sutures and an of overall collage-type tectonics of that area. The main lithostratigraphical components distinguished within the Sudetes are: 1) non-metamorphic to metamorphosed Neoproterozoic igneous suites accompanied by volcano-sedimentary successions, 2) Late Cambrian granitoids gneissified during the Variscan orogeny, 3) variously metamorphosed Ordovician through Devonian volcano-sedimentary successions deposited in pre-orogenic extensional basins, 4) dismembered fragments of a Late Silurian ophiolitic complex, 5) Devonian to Lower Carboniferous sedimentary successions of a passive continental margin, 6) Carboniferous granitoids, and 7) clastic sediments of Devonian and/or Early Carboniferous intramontane basins. All these components are assembled to form part of the internal Variscan orogenic zone largely exposed within the area of the Bohemian Massif. A three-partite subdivision of the Sudetes proposed here reflects different timing of deformation and exhumation of the respective segments. The Central, West and East Sudetes were deformed and amalgamated during the Middle/Late Devonian, at the turn of the Devonian and Carboniferous and during Early Carboniferous, respectively. Problems in extending the classical tectonostratigraphic zonation of the Variscides into the Sudetes are explained as due to activity of Late Palaeozoic strike-slip faults and shear zones, disrupting and dispersing the initially more simply distributed tectonostratigraphic units into the present-day structural mosaic.

12

Overview of magmatism in Northwestern Vietnam

Khuong H.

Annales Societatis Geologorum Poloniae

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2010

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Vol. 80, No 2

185-226

EN

Amalgamation of tectonic plates of Southeast Asia occurred in northwestern Vietnam. Six groups of magmatic rocks are related to the tectonic events. The first group corresponds to the major episodes of crustal formation in the South China block, or is linked with the formation of Gondwana. The second group includes granitoids in connection with the collision and formation of the Caledonian-Hercynian folding event. The third group contains Upper Permian ophiolites, as well as the Permian extrusives, formed in intraplate setting, related to back-arcs spreading. The fourth group is related to Triassic Indosinian orogeny, the fifth group comprises Jurassic-Cretaceous intraplate granitoids. Finally, during Cenozoic times, magmatic rocks were represented by alkaline granitoids - the effect of strike-slip faulting related to the collision of India and Eurasia plates.

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Hydrothermal veins linked with the Variscan structure of the Prague Synform (Barrandien, Czech Republic): resolving fluid-wall rock interaction

Halavínová M., Melichar R., Slobodník M.

Geological Quarterly

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2008

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Vol. 52, No 4

309-309

EN

Variscan syntectonic hy dro ther mal veins of the Prague Synform are important traces of small-scale fluid migration in Lower Palaeozoic sedimentary rocks — a process induced by late Variscan tectogenesis. Two main structural types of Variscan syntectonic calcite veins were recognised during fieldwork. Veins of Type I have an irregular or sigmoidal shape and are often arranged in en echelon arrays. A shearing regime during the formation of this type is deduced. Veins of a second structural type (Type II) have a more regular and straight shape relative to those of Type I and in some places form a dense network. The structural position of the Type II veins is related to structural elements of Variscan folds. Veins were formed due to interlayer-slip combined with fold- related fracturing that gave rise to the infilling of dilational structures. A tensional regime also permits growth of the fibrous veins. Two princpal directions were distinguished within the Type II veins. The first one is NNW–SSE and the second one shows a perpendicular ENE–WSW orientation. These directions seem to be parallel and/or perpendicular to the nappearchitec ture of the Prague Synform. Variscan syntectonic veins crystallised in a relatively closed, rock-buf fered system. Extraction of chemical components from surrounding rocks is indicated by a combined microprobe/cathodoluminescent study and by isotope geochemistry. The carbon isotope values of hydrothermal calcites reflect the carbon isotope composition of the host rocks. The delta exp.13C values of vein calcites and their host Silurian rocks are between –0.29 and –1.98‰ PDB. The same relationships were found between the veins and the host Devonian limestones (from 1.72 to 2.52‰ PDB). Samples close to the Silurian/Devonian boundary show transition values between 0.25 and + 1.16‰ PDB. The Sr-isotopic signature supports a genetic link between the calcite veins and the host rocks. The 87Sr/86Sr ra tio in calcites ranges between 0.708619 and 0.708738 and in wall rocks be tween 0.708755 and 0.709355. Aqueous and hydrocarbon-rich fluid systems have been found in fluid inclusions. Liquid hydrocarbons show mostly a light blue fluorescence suggesting the presence of higher hydrocarbons. They are more abundant in dark Silurian rocks, which are rich in organic matter. Lower salinities (0.5–8.9 eq. wt.% NaCl) and homogenization temperatures with a maximum around 140gradeC are typ i cal for the aqueous (H2O–NaCl) system. The oxygen isotopic composition of fluids ranges between –2.80 and +3.33‰ SMOW. This indicates that transformed formation waters in teracted with the host rocks and/or deeply circulating isotopically depleted meteoric waters. Intersections with the isochore specify border trapping temperatures between 127 and 160grade C and pressures from 300 to 1070 bars.

14

Neoproterozoiczny rozpad superkontynentu Rodinii/Pannotii – zapis w rozwoju basenów osadowych na zachodnim skłonie Baltiki

Poprawa P.

Prace Państwowego Instytutu Geologicznego

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2006

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T. 186

165--188

PL

W neoproterozoiku wzdłuż zachodniej krawędzi kratonu wschodnioeuropejskiego zachodziły procesy ryftowe, najprawdopodobniej związane z rozpadem prekambryjskiego superkontynentu Rodinii/Pannotii. Proces ten doprowadził do powstania pasywnej krawędzi kontynentalnej Baltiki, która w trakcie paleozoicznych kolizji i/lub ruchów przesuwczych ewoluowała w strefę szwu transeuropejskiego. W czasie równowiekowego, w przybliżeniu, ryftowania wzdłuż zachodniej krawędzi kratonu wschodnioeuropejskiego oraz wzdłuż poprzecznych do niej norweskiej krawędzi kratonu oraz strefy Orsza–Wołyń powstawały węzły potrójne. Datowania izotopowe skał wulkanicznych i piroklastycznych związanych z ryftowaniem, a także ich pośrednie datowania paleomagnetyczne oraz przesłanki z ilościowej analizy krzywych subsydencji zawężają czas synryftowej aktywności magmowej do późnego neoproterozoiku. Późnoneoproterozoiczna ekstensja i dywergencja płyt wzdłuż zachodniej krawędzi Baltiki kontrastuje z, w przybliżeniu równowiekową, konwergencją i kolizją orogeniczną oraz fliszowym wykształceniem facjalnym utworów ediakaru na bloku małopolskim oraz Brunovistulikum. Również historię kambryjskiej subsydencji basenu rozwiniętego na Brunovistulikum, charakteryzującą się intensywnym zdarzeniem tektonicznym we wczesnym kambrze, trudno pogodzić z modelem subsydencji zachodniej Baltiki, o ile założyć paleogeograficzne relacje obu domen zbliżone do obecnych. Przyjęto, iż w ediakarze Baltika oraz Brunovistulikum były od siebie odległe. Akrecja bloku małopolskiego do Baltiki zachodziła, począwszy od kambru, w wyniku skośnej konwergencji. Za przejaw kolizyjnego dołączania bloku małopolskiego do Baltiki uznano fazy wypiętrzania tektonicznego i erozji, mające miejsce w basenie bałtyckim i basenie lubelsko-podlaskim pod koniec środkowego kambru oraz w późnym kambrze. W modelu takim relatywnie duże miąższości górnego kambru w strefie łysogórskiej Gór Świętokrzyskich oraz w strefie Narola można tłumaczyć zjawiskiem fleksuralnego uginania krawędzi Baltiki w czasie kolizji. W odniesieniu do dolno- do środkowokambryjskiego basenu sedymentacyjnego, rozwiniętego w SE części Brunovistulikum, zaproponowano model fleksuralnego basenu przedgórskiego.

EN

During the Neoproterozoic, rift zones developed along the western slope of the East European Craton (EEC), most probably related to break-up of the Precambrian supercontinent Rodinia/Pannotia. Rifting along the SW margin of the EEC was roughly coeval with rifting along its Norwegian margin, as well as along the Orsha-Volyn Aulacogen, resulting in development of the triple junctions. Subsequently, during Cambrian to Middle Ordovician time, the passive continental margins developed along the western slope of newly formed Baltica. In Ediacaran time, the Brunovistulicum terrane was separated from Baltica. Collision of the Małopolska block with Baltica caused the late Cambrian flexural subsidence in the Łysogóry unit of the Holy Cross Mountains and in the Narol zone, as well as tectonic uplift and erosion in the Baltic Basin and the Lublin-Podlasie Basin. The Lower to Middle Cambrian sedimentary basins, developed in the SE part of Brunovistulicum, are tentatively interpreted as a flexural basin formed in a foreland of a suspected Cambrian collision zone.

15

The Variscan Orogen in Poland

Mazur S., Aleksandrowski P., Kryza R., Oberc-Dziedzic T.

Geological Quarterly

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2006

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Vol. 50, No. 1

89-118

EN

The structure and evolution of the Polish part of the Variscan Orogenic Belt is reviewed, based on published data and interpretations. The Sudetic segment of the Variscides, together with adjacent areas, experienced multi-stage accretion during successive collisional events that followed the closure of different segments of the Rheic Ocean. In SW Poland, Variscan tectono-stratigraphic units are tectonically juxtaposed and often bear record of contrasting exhumation/cooling paths, constrained by palaeontological and geochronological data. This points to the collage-type tectonics of this area. A three-partite subdivision of the Sudetes is proposed that reflects timing differences in deformation and exhumation of the respective segments. The Central,West and East Sudetes were deformed and amalgamated during the Middle/Late Devonian, at the turn from the Devonian to Carboniferous and during Early Carboniferous times, respectively. Problems in extending the classical tectono-stratigraphic zonation of the Variscides into the Sudetes are discussed and attributed to activity along Late Palaeozoic strike-slip faults and shear zones, disrupting and dispersing the initially more simply distributed tectono-stratigraphic units into the present-day structural mosaic. Relationships between the Variscan Externides and the foreland basin are explored. Sediments of the foreland basin locally onlap the external fold-and-thrust belt that had undergone an earliest Carboniferous partial tectono-thermal overprint. During the Late Carboniferous, the SW part of the foreland basin was heavily affected by thrusting and folding and incorporated into the Externides. DuringWestphalian C to Early Permian times, localized folding and thrusting affected the distal parts of the foreland basin, probably in response to dextral transpressional movements along NW–SE trending basement faults.

16

Stratygrafia dewońsko-karbońskiej serii węglanowej w rejonie Rajbrotu i Tarnawy

Matyja H., Tomaś A., Lipiec M., Turnau E.

Prace Państwowego Instytutu Geologicznego

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2001

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T. 174

33--60

PL

Zintegrowane badania biostratygraficzne, polegające na równoczesnym badaniu tych samych profilów przy pomocy konodontów, otwornic i palinomorf, aczkolwiek nie dały w pełni satysfakcjonujących wyników, pozwoliły na datowanie granic jednostek litostratygraficznych wyróżnionych przez Narkiewicza (2001), na dość wiarygodną wzajemną korelację profilów, przynajmniej na poziomie chronostratygraficznym, na oszacowanie rozmiaru lokalnych luk erozyjnych, a w przyszłości stać się mogą podstawą do szerszych korelacji na skalę regionalną. Początek sedymentacji węglanowych osadów dewońskich przypada w analizowanym obszarze na przełom wczesnego i środkowego dewonu, na pogranicze emsu i eiflu. W obrębie serii węglanowej stwierdzono obecność niewielkiej miąższości osadów środkowego dewonu, prawdopodobnie franu (jego obecności można się jedynie domyślać na podstawie położenia w profilach, brak jest natomiast, jak na razie, datowań biostratygraficznych), relatywnie dużej miąższości datowanych osadów famenu oraz turneju i wizenu: hastaru i iworu, prawdopodobnie również czadu i arundu, a także dobrze datowanego holkeru. Granica między dewonem a karbonem przebiega w obrębie jednej jednostki litostratygraficznej, kompleksu wapieni gruzłowych i ziarnistych, ale jej natura — ciągłość sedymentacji między dewonem a karbonem z objawami spłycenia, jak to ma miejsce w części profilów na świecie, czy też luka erozyjna — pozostaje nadal nieznana. Sedymentacja osadów węglanowych karbonu trwała w badanym obszarze od końca emsu lub początku eiflu aż do wizenu, co najmniej po holker, natomiast sedymentacja osadów klastycznych rozpoczęła się być może już w asbie, a na pewno w namurze, prawdopodobnie w arnsbergu—w dobie triangulus-knoxi (TK), jak wynika z badań Trzepierczyńskiej (2001). Obserwowana luka o tektoniczno-erozyjnym charakterze obejmuje więc późny wizen, asb i brigant. W żadnym z badanych trzech profilów nie znaleziono osadów tego wieku, natomiast w najwyższych partiach serii węglanowej w profilu Tarnawa 1, wydatowanych na podstawie otwornic jako wyższy turnej — iwor, zona Tournayella (Cf2), znalezione zostały w odwróconym porządku stratygraficznym, w niewielkim stopniu wymieszane, zespoły miospor identyfikujące wspomniane brakujące piętra najwyższej części wizenu, niżej miospory dolnej części brigantu (zona VF), wyżej asbu (zony TC i NM). W dolnych partiach osadów klastycznych w profilu Tarnawa 1, datowanych jako namur (prawdopodobnie arnsberg), notowane są również liczne i zróżnicowane taksonomicznie miospory, reprezentujące poziomy TC i NM asbu oraz poziom VF brigantu. Taki zapis stratygraficzny na pograniczu serii węglanowej i klastycznej w profilu Tarnawa 1 sugeruje dość skomplikowany scenariusz procesów i zdarzeń geologicznych, jakie mogły mieć miejsce w tym niewielkim obszarze pod koniec wizenu i na początku namuru: (1) depozycję osadów węglanowych prawdopodobnie aż po holker; (2) śródwizeński epizod tektoniczno-erozyjny, w wyniku którego usuwane mogły być węglanowe osady holkeru, arundu, czadu i części iworu; (3) prawdopodobnie depozycję niewielkiej miąższości klastycznych osadów asbu, brigantu i pendleju; (4) późnowizeński epizod tektoniczno-erozyjny, w wyniku którego usuwane być mogły sukcesywnie klastyczne osady pendleju, brigantu i asbu i (5)uruchomienie sedymentacji w namurze - prawdopodobnie w Arnsbergu.

EN

The subdivision in lithostratigraphical units presently used (Narkiewicz 2001) is schematically shown on Figure 4. Biostratigraphy of the Devonian and Carboniferous in the Tarnawa-Rajbrot area has been established using conodonts and foraminifers and palynomorphs. The three microfossil groups used in conjunction can facilitate better precision in dating and correlating of sequences. Unfortunately, for most of the Devonian and Lower Carboniferous limestone succession, the miospores recovered tend to be too much oxidized and poorly preserved to be useful. They are routinely used in the siliciclastic part of the sequence. Unfortunately, the biostratigraphic evidence is too much incomplete to firmly establish the boundary between the lithostratigraphic units as well as between the Devonian and Carboniferous successions (see Figure 4). Marly dolostones and limestones with bioturbations (DWMB) spans the Middle Devonian, limestones, dolomicrites and dolosparites (WDD) include part of the Middle Devonian, probably Frasnian and part of the Famennian. Nodular and grained limestones unit (WGZ) include the uppermost part of Famennian and part of the Tournaisian (up to the isosticha-Upper crenulata conodont Zone). The Devonian-Carboniferous boundary runs within this lithostratigraphic units but its nature remains unknown. Marly horizon (PM) spans the uppermost isosticha-Upper crenulata-Lower typicus conodont zones (Tournaisian - Ivorian), grained limestones (WZ) include upper part of the Tournaisian (Ivorian to Arundian), and upper limestones and marls unit (WGM) belong to the Viséan (Holkerian, Cf5 foraminifer Zone). Using the integrated results of conodont, foraminifer and palinomorph studies it is possible to conclude that the limestone succession spans the Middle and Upper Devonian, Tournaisian and much of the Viséan, up to the Holkerian. The siliciclastic sedimentation starts certainly at the begining of the Namurian (see Trzepierczyńska, 2001), maybe earlier (during the ?Asbian). There is a significant hiatus at the erosional boundary between the carbonate and clastic sequences which may span the late Asbian and Brigantian. Deposits of this age have been found in none of the three borehole sections. The uppermost t parts of the carbonate series of the Tarnawa 1 borehole, dated by foraminifers as the Upper Tournaisian Ivorian, Tournayella Zone, yielded miospore assemblages, which point to the above-mentioned missing stages of the uppermost Viséan, but occurring in a reverse stratigraphic order (lower in the sections younger miospores of the Brigantian VF zone, above in the section older miospores of the Asbian TC and NM zones). In the lower parts of the clastic sequence of the Tarnawa 1 borehole, dated as the Namurian (probably Arnsbergian), abundant and taxonomically diverse miospores representing the Asbian TC and NM, as well as Brigantian VF Zone, were also found. Such a stratigraphic record of the carbonate/clastic transition zone from the Tarnawa 1 borehole section suggests a fairly complicated succession of events, that may have taken place over this small area at the end of Viséan and beginning of the Namurian: (1) carbonate sedimentation, probably until the Holkerian (by analogy to the Rajbrot 2 borehole section); (2) Mid-Viséantectonic-erosional event that may have caused the removal of the Holkerian, Arundian, Chadian and a part of Ivorian deposits; (3) probable deposition of small thickness Asbian, Brigantian and Pendleian clastics; (4) Late-Viséan tectonic-erosional event which might have resulted in the removal of Pendleian, Brigantian and Asbian clastics; (5) renewal of deposition in the Namurian, probably Arnsbergian. Ivorian to Arundian), and upper limestones and marls unit (WGM) belong to the Viséan (Holkerian, Cf5 foraminifer Zone). Using the integrated results of conodont, foraminifer and palinomorph studies it is possible to conclude that the limestone succession spans the Middle and Upper Devonian, Tournaisian and much of the Viséan, up to the Holkerian. The siliciclastic sedimentation starts certainly at the begining of the Namurian (see Trzepierczyńska, 2001), maybe earlier (during the ?Asbian). There is a significant hiatus at the erosional boundary between the carbonate and clastic sequences which may span the late Asbian and Brigantian. Deposits of this age have been found in none of the three borehole sections. The uppermost tparts of the carbonate series of theTarnawa 1 borehole, dated by foraminifers as the Upper Tournaisian Ivorian, Tournayella Zone, yielded miospore assemblages, which point to the above-mentioned missing stages of the uppermost Viséan, but occurring in a reverse stratigraphic order (lower in the sections younger miospores of the Brigantian VF zone, above in the section older miospores of the Asbian TC and NM zones). In the lower parts of the clastic sequence of the Tarnawa 1 borehole, dated as the Namurian (probably Arnsbergian), abundant and taxonomically diverse miospores representing the Asbian TC and NM, as well as Brigantian VF Zone, were also found. Such a stratigraphic record of the carbonate/clastic transition zone from the Tarnawa 1 borehole section suggests a fairly complicated succession of events, that may have taken place over this small area at the end of Viséan and beginning of the Namurian: (1) carbonate sedimentation, probably until the Holkerian (by analogy to the Rajbrot 2 borehole section); (2) Mid-Viséantectonic-erosional event that may have caused the removal of the Holkerian, Arundian, Chadian and a part of Ivorian deposits; (3) probable deposition of small thickness Asbian, Brigantian and Pendleian clastics; (4) Late-Viséan tectonic-erosional event which might have resulted in the removal of Pendleian, Brigantian and Asbian clastics; (5) renewal of deposition in the Namurian, probably Arnsbergian.

17

Morphometric evolution and phylogeny of Palaeozoic ammonoids. Early and Middle Devonian

Korn D.

Acta Geologica Polonica

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2001

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Vol. 51, nr 3

193-215

EN

A combination of methods from cladistics and stratophenetic analyses is used for a reconstruction of Early and Middle Devonian ammonoid phylogeny. The analyses are based mainly on principal characters such as conch geometry (coiling form, whorl expansion rate, whorl cross-section shape), septal geometry (form of septa, number, position, and shapes of lobes), and ornament (growth lines and ribs); a new classification scheme of the ancient ammonoid order Agoniatitida is proposed. It is subdivided into four suborders: Agoniatitina (paraphyletic), Gephuroceratina (monophyletic), Anarcestina (paraphyletic), and Pharciceratina (monophyletic). Morphometric analysis shows the unfolding of several morphological trends, such as the modification of coiling parameters, among the Early and Middle Devonian ammonoids. Two major independent lineages can be recognised in the phylogeny of the Middle Devonian ammonoids, the first represents the agoniatids in which the Gephuroceratina is nested, the second are the anarcestids which gave rise to the Pharciceratina. The new families Latanarcestidae, Tamaritidae, Atlantoceratidae, and Taouzitidae, as well as the new genera Taouzites, Croyites and Meragoniatites are introduced.

18

Palaeozoic orogeneses in the Sudetes: a geodynamic model

Cymerman Z.

Geological Quarterly

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2000

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Vol. 44, Nr 1

59-80

EN

The Palaeozoic geodynamic evolution of the Sudetes resulted from two successive orogenic events: (1) Ordovician-Silurian geotectonic processes (pre-Variscan stages), and (2) the Variscan orogeny. Early Palaeozoic rifting of Cadomian crustal segments and opening of the Ligerian (Galicia-Massif Central) and/or Saxothuringian Ocean occurred in Ordovician-Silurian times on the northern (peri-Gondwana) periphery of the Bohemian Massif. At the same time, the Góry Sowie terrane with a magmatic arc affinity quite probably developed on the SW margin of Baltica due to subduction of the Tornquist Ocean. Two major structural events characterised the Variscan evolution of the Sudetes: (1) regional-scale ductile thrusting of Late Devonian-Early Carboniferous age, and (2) Early Carboniferous-Early Permian regional extension. Ductile thrusting is characterised by: (I) a general NNE-directed, dextral transpressional stacking of ductile nappes due to oblique collision of the Moldanubian and Moravian microplates in the Eastern Sudetes, and (II) SW- to NW-directed, sinistral transpressional stacking of ductile nappes due to westward lateral extrusion of continental crust in the Central and Western Sudetes, itself a result of oblique indentation of the Central Sudetic oceanic lithosphere. The first Variscan deformation in the Sudetes might reflect a purely convergent setting that evolved into a transpressive setting during oblique convergence. Special attention is given to the geometry and kinematics of intraplate tectonic escape and a model of indentation processes in the Sudetes. The presented new geotectonic model for the Variscan evolution of the Sudetes is consistent with lateral escape of the Saxothuringian terrane as an important way of accommodating Variscan strain in the NE part of the Bohemian Massif. This model explains the lateral expulsion (escape) process as due to the indentation of the Central Sudetic terrane along with the Góry Sowie terrane and by the oblique subduction of the Ligerian/Saxothuringian Ocean(s) (now tectonically dismembered ophiolitic rocks of the Central Sudetic terrane).