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EN
Concepts prevailing among the Polish geoscientists during the last decades assumed that the Teisseyre-Tornquist Zone is a major tectonic discontinuity separating the pre-Ediacaran East European Craton (EEC) crust from the Paleozoic Platform composed of terranes accreted during the Caledonian and Variscan orogenic processes. The recent interpretations of the TTZ by Mazur and collaborators, basedon gravity modelling and new PolandSPAN seismic reflection data, revive earlier ideas of the EEC crust extending to the western Poland and NE Germany. These authors propose that the TTZ is in fact a Sveconorwegian (ca. 1 Ga old) collisional suture marked by a crustal keel expressed as the Pomeranian and Kuiavian gravity lows in northern and central Poland. However, the present review of seismic data available, as well as a closer evaluation of the modelling results, do not confirm the keel/suture concept. On the other hand, the idea of the TTZ as an Early Paleozoic tectonic discontinuity is supported by several lines of evidence, including a strong regional magnetic gradient and a contrast in the crustal structure. The latter is revealed by seismic velocity distribution from the refraction data, in the results of magnetotelluric profiling and in recent seismicity patterns. The interpretation of the PolandSPAN data attempting to prove the continuity of the cratonic crust and its Ediacaran-Lower Paleozoic cover across the TTZ appears questionable. At the same time the POLCRUST-01 deep seismic profile in SE Poland documents that the zone is associated with the subvertical Tomaszów Fault. The basement top displacement by ca. 0,5 km and associated change in its slope are related to the fault whose deep crustal roots are further documented by reflectivity patterns in the lower crust. The recent modelling exercise by Krzywiec and collaborators aimed at questioning the thick-skinned nature of this fault does not present compelling results, being based on a poorly constrained geological model. The general conclusion from the present review is that the recently published data either support or at least do not contradict the concept of the TTZ as a tectonic zone separating the continuous EEC crust from several allochtonous blocks - mostly proximal Early Paleozoic terranes to the south-west. Thelithospheric memory of the TTZ echoed in successive stages of its reactivation in different intra-plate tectonic regimes - transpressive Variscan, mostly extensional or transtensional Permian through Early Cretaceous, compressional Late Cretaceous and finally Neogene, related to the Carpathian orogenic compression.
EN
Authorial comprehensive comments and explanations are given to some of the interpretations applied in the tectonic part of the newly published Geological Atlas of Poland (Nawrocki, Becker, 2017) that considerably change the hitherto generally accepted concepts. It should be, however, admitted that most of those "new’" solutions were already proposed in the past by other workers as hypotheses that could not have been tested in the then state of knowledge on Poland’s deep geology and scientific tools at hand. This has now changed with abundant new data obtained with modern seismic techniques and advanced methods of potential field modelling. Using those data, we justify the reasons for, among others, a significant eastward shifting the front of the Variscan Orogen in Poland andfor the accompanying change in position of the division line between the Precambrian and Palaeozoic platforms. We also show the rationale for accepting a far-reaching southwestward extent of the East European Craton’s crystalline basement below the Palaeozoic Platform and for reinterpretation of the Teisseyre-Tornquist Zone’s nature, together with the question of early Palaeozoic terranes in the TESZ and the situation of the Caledonian foredeep at the SW margin of the East-European Craton.
3
Content available Wawrzyniec i Henryk Teisseyre’owie
EN
The Teisseyre family is a very meritorious family in Polish geology. Senior Wawrzyniec Teisseyre (1860–1939), cartographer, tectonicist, petroleum geologist and paleontologist, first determined the course of the SW boundary of the East European Platform, subsequently confirmed by magnetic studies of German geophysicist A.J.H. Tornquist. This important continental-scale feature has a character of deep fractures and is called today the Teisseyre-Tornquist Zone. Wawrzyniec's son, Henryk Teisseyre (1903–1975), was an eminent Carpathian geologist. After World War II, he was the co-founder of the Wroc³aw centre of Polish geology and the creator of Wroc³aw school of tectonics. Significant roles in the geology were played by Henryk's sons: prematurely died Juliusz (1933–1991) and Andrzej Karol (1938–1991). Henryk's nephew, Roman Teisseyre (born 1929), is a world-class seismologist, researcher in physics of the Earth interior.
EN
The interpretation of the geodynamic phenomena with the use of GPS observations strongly depends on the quality of the terrestrial reference frame. The aim of this contribution is to verify station velocities from recent ITRF/ETRF solutions as well as to evaluate the possible geodynamic processes by using long time series of GPS data from four permanent GNSS stations operating in T-T zone. The components of four baselines were calculated with the use of the Bernese v.5.0 GPS software using GPS observation data from 2004–2012. Time variations of baseline components and baseline length were analysed and their linear trends were estimated by applying linear regression analysis. The obtained results have indicated that the variations are within the range from –0.2 to 0.3 mm/year in X–component, from –0.6 to –0.3 mm/year in Y–component, from –0.2 to 0.2 mm/year in Z–component and from –0.2 to 0.6 mm/year for the baseline length. The estimated linear trends of baselines components variations fit substantially better to the respective ones derived from ITRF2008/ETRF2000 (R8) than to the ones from ITRF2005/ETRF2000 (R5).
PL
Możliwość interpretowania zjawisk geodynamicznych na podstawie analizy obserwacji GPS w dużej mierze zależy od jakości ziemskiego układu odniesienia. Celem niniejszej pracy jest zweryfikowanie prędkości stacji uzyskanych ze współczesnych rozwiązań ITRF/ETRF, a także ocena ewentualnych procesów geodynamicznych przy użyciu długiego szeregu czasowego obserwacji na stacjach permanentnych GNSS położonych w rejonie strefy Teisseyre’a-Tornquista. Składowe czterech wektorów obliczono przy użyciu programu Bernese v.5.0 z obserwacji GPS z lat 2004–2012. Poddano analizie zmiany czasowe składowych tych wektorów oraz ich długości; przy wykorzystaniu analizy regresji wyznaczono trendy liniowe tych zmian. Rezultaty analiz wskazują na zmiany w przedziałach -0.2 do 0.3 mm/rok w składowej X, -0.6 do -0.3 mm/ rok w składowej Y, -0.2 to 0.2 mm/ rok w składowej Z oraz -0.2 do 0.6 mm/ rok w długości wektora. Wyznaczone trendy liniowe zmian składowych wektorów wykazują znacząco lepszą zgodność z odpowiednimi zmianami otrzymanymi z rozwiązań w układach ITRF2008/ETRF2000 (R8) niż ze zmianami z rozwiązań w układach ITRF2005/ETRF2000 (R5).
EN
The sedimentary cover of the SW margin of the East European Craton (EEC) records its Mesozoic evolution from Permian to Early Maastrichtian time. Structural units of the Mid-Polish Swell with bounding synclines, the Stryi Depression, the Moldavian Platform, the Pre-Dobrogea Depression (PDD) and the North Dobrogea (ND) are groupped along the Teisseyre-Tornquist Zone (TTZ), one of the most important lineaments of the European Plate. They developed above the Trans-European Suture Zone (TESZ), the contact zone of Precambrian and Palaeozoic domains of crustal consolidation. The investigated area forms a belt 1000 km long that strikes across four states down to the Black Sea. The stratigraphy and facies data based on the profiles from many hundreds of wells and outcrops are summarized on thickness and lithofacies maps covering 16 time-spans. They show palaeogeogra- phic history of sedimentary basins of the SE part of Mid-Polish Trough (MPT), the Stryi Depression and the Pre-Dobrogea Depression. Fragmentary record of epicontinental sediments in the ND could be interpreted referring to depositional history of the PDD. The facies-thickness maps were transfor- med to maps of accumulation rate reflecting subsidence rates. Sedimentary and structural evolution of the two outermost basins, MPT and PDD, give evidences for their genetic independence and the lack of their direct connections along direction of TTZ till the end of Jurassic time. The Triassic-Middle Jurassic evolution of the North Dobrogea suggests that it could lie farther to the SW in the Tethyan realm. Deep-water sequences of the ND did not display any relation to the epiplatform sediments in the PDD up to the Bathonian. Mid-Cimmerian transpressional docking of the ND block to the PDD gave the beginning of their common epicontinental Jurassic history with subsidence axis striking W-E. Geometric junction of both external basins (MPT and PDD) in NW-SE direction occurred during the Early Cretaceous as a result of origin of foredeep basin located to the north of the ND inverted block, together with the western part of the PDD. Inversion was a consequence of the Neo-Cimmerian collision in the Northern Tethys and docking of the Central Dobrogea to the ND. The evolution of the PDD was connected with the eastern Mediterranean realm from Albian time on. A multiphase (10 stages) tectonic history of the Mid-Polish Trough and the Stryi Depression was recognized. Clockwise rotation of the two principal stress axes in horizontal plane controlled basin opening. A change of the strike-slip component along the TTZ direction and over the TESZ occurred from sinistral (Early Jurassic), through the lack of horizontal displacements in Albian-Cenomanian time, to dextral component from the Turonian till the end of Cretaceous. During the inversion the s1 axis reached a NE-SW orientation.
6
Content available remote Kreda w regionie lubelskim - sedymentacja i jej tektoniczne uwarunkowania
PL
Praca ma charakter przeglądowy; zawiera odniesienia do publikacji zajmujących się osadami kredy obszaru lubelskiego: ich pozycją strukturalną, litologią, warunkami sedymentacji i warunkami paleotektonicznymi. Ewolucja basenu została scharakteryzowana na podstawie map litofacji i tempa subsydencji 7 przedziałów czasowych. Podkreślono związki rozkładu litofacji i subsydencji ze strukturami paleozoicznego i prekambryjskiego podłoża. Ewolucję paleotektonicznych warunków, kształtujących przestrzeń depozycyjną, interpretowano na podstawie lokalizacji przypuszczalnych stref synsedymentacyjnych uskoków i fałdów. Przedstawiono przesłanki na rzecz początku inwersji lubelskiego odcinka bruzdy śródpolskiej we wczesnym mastrychcie.
EN
The aim of the study is to give an overview of research dealing with Cretaceous deposits in the Lublin region, i.e. their structural position, lithology, sedimentary and palaeotectonic conditions. Reconstruction of the Cretaceous basin evolution is based on lithofacies maps and on maps of subsidence rates made for 7 time spans. Relations of lithofacies and subsidence patterns with Palaeozoic and Precambrian basement structures are emphasized. Interpretation of synsedimentary faults and folds enabled conclusions on palaeotectonic conditions that created the depositional space. Some remarks concerning Early Maastrichtian timing of the onset of inversion processes is also presented.
EN
The Cretaceous basin of the Lublin area belongs to the SE part of the Mid-Polish Trough and its NE border extending on the East European Craton. Our study is based on isopach maps of seven time intervals, from Neocomian to Early Maastrichtian. Several main lithofacies have been distinguished whose areal extents were plotted on thickness pattern maps. The isopach and lithofacies maps helped to delimit the basin depocenter, providing information on vertical motions of the basin basement and synsedimentary reactivation of older fault zones. The areal extents of the siliceous and chalk lithofacies have been shown to be controlled by the positions of discontinuity zones in the crystalline basement. Two stages of accelerated subsidence have been established: in Turonian and Early Maastrichtian times. Regional comparisons of accumulation rates and their accelerations during these time spans gave possibility to distinguish the roles of eustatic and tectonic factors in the process of augmenting the basin capacity. Some remarks concerning Early Maastrichtian timing of the inversion onset are also presented.
PL
Analiza danych grawimetrycznych i magnetycznych została wykonana w rejonie Polski centralnej. Obszar badań obejmuje kujawski segment strefy szwu transeuropejskiego (Trans-European Suture Zone - TESZ). O ile kompleks cechsztyńsko-mezozoiczny tego rejonu jest stosunkowo dobrze rozpoznany, to wiedza geologiczna i geofizyczna o niżej leżących kompleksach paleozoicznych i skorupie krystalicznej na przedpolu kratonu wschodnioeuropejskiego jest uboga. W tej sytuacji szczególnego znaczenia nabiera analiza danych pól potencjalnych. Zastosowano wiele metod interpretacji opartych na cyfrowym przetwarzaniu danych grawimetrycznych i magnetycznych. Analiza pola anomalii różnicowych i danych magnetycznych, wyniki trójwymiarowej inwersji lokalnych anomalii różnicowych oraz modelowanie grawimetryczne wzdłuż wybranego profilu pozwoliły na sformułowanie kilku wniosków dotyczących budowy skorupy ziemskiej w analizowanym obszarze. Stwierdzono, że skorupa w podłożu bruzdy kujawskiej jest silnie zróżnicowana. Główny podział wyznacza silna strefa gradientowa w polu anomalii różnicowych, której położenie odpowiada cechsztyńsko-mezozoicznej strefie uskokowej Brześć Kujawski-Wojszyce. Na SW od niej duże miąższości podcechsztyńskiego kompleksu paleozoicznego są prawdopodobnie źródłem niżu grawimetrycznego Mogilno-Kłodawa. Wniosek ten ma duże znaczenie dla poszukiwań ropy i gazu. W obrębie niżu grawimetrycznego Mogilno-Kłodawa utwory paleozoiczne i ich podłoże jest silnie zuskokowane, tworząc poprzesuwane pionowo bloki. Na NE od strefy Brześć Kujawski-Wojszyce pole grawimetryczne o wysokich wartościach jest mało zróżnicowane. Ten wyż jest spowodowany przez głębokie źródła o podwyższonej gęstości. Pole magnetyczne wskazuje na głęboko zalegające podłoże magnetyczne i istnienie głęboko pogrążonej strefy uskoków przesuwczych związanych ze strefą zrzutowo-przesuwczą Sieradz-Łowicz w kompleksie cechsztyńsko-mezozoicznym. Niektóre lineamenty magnetyczne korelują się z układem strukturalnym obserwowanym w kompleksie cechsztyńsko-mezozoicznym, co świadczy o wpływie struktur głębszego podłoża na tektoniczną ewolucję piętra fanerozoicznego. Jeden z nich, fragmentarycznie śledzony wzdłuż linii biegnącej przez Inowrocław, Włocławek i Płock, jest zapewne związany z hipotetyczną, regionalną strefą uskokową Chodzież-Włocławek-Płock-Warszawa. Modelowanie grawimetryczne wzdłuż profilu potwierdza możliwość istnienia znacznych miąższości paleozoiku podcechsztyńskiego oraz sugeruje, że krystaliczna skorupa platformy paleozoicznej, o cechach skorupy waryscyjskiej, sięga w okolice głębokiej strefy dyslokacyjnej Mogilno-Ponętów-Wartkowice. Przeprowadzona interpretacja umożliwiła lepsze poznanie tektonicznego charakteru rejonu i związków strukturalnych między głębokimi i płytszymi strukturami.
EN
The analysis of gravity and magnetic data has been made for central Poland. The study area comprises the Kujavian segment of the Trans-European Suture Zone (TESZ). The Zechstein-Mesozoic complex of this region is relatively well known but geological and geophysical knowledge on the underlying Palaeozoic complexes and crystalline crust at the East European Craton forefield is still poor. Therefore, a particular importance is being acquired by the analysis of potential field data. Various interpretation methods basing upon digital processing of gravity and magnetic data have been employed. The analysis of stripped gravity anomalies and magnetic data, results of 3D inversion of residual stripped gravity anomalies, and gravity modelling along a selected profile, have allowed to draw a few conclusions on the Earth's crust structure in this area. It has been recognized that the crust underlying the Kujavian segment of the Mid-Polish Trough is strongly diversified. Its main division line is defined by a strong gradient zone of the stripped gravity field whose position corresponds with the Zechstein-Mesozoic fault zone of Brześć Kujawski-Wojszyce. South-west of this zone, much thicknesses of the sub-Zechstein Palaeozoic complex probably result in the Mogilno-Kłodawa gravity low. This conclusion has a great importance in prospecting for oil and gas. Palaeozoic deposits and their basement is strongly faulted within the Mogilno-Kłodawa gravity low, forming vertically shifted blocks. North-east of the Brześć Kujawski-Wojszyce zone, the high-value gravity field is poorly differentiated. This high results from deep-seated sources of higher densities. The magnetic field data point to a deep-lying magnetic basement. They are indicative of the occurrence of a deep strike-slip fault zone related to the major oblique slip Sieradz-Łowicz fracture zone within the Zechstein-Mesozoic complex. Some of magnetic lineaments well correlate with a structural pattern visible within the Zechstein-Mesozoic complex. This is indicative of the influence of deep basement structures on tectonic evolution of the Phanerozoic sequence. One of them, fragmentarily observed along the line Inowrocław-Włocławek-Płock, is probably related to the hypothetical fault zone of Chodzież-Włocławek-Płock-Warszawa. Gravity modelling along the profile confirms possibility of the occurrence of considerable thicknesses of the sub-Zechstein Palaeozoic complex, and suggests that the crystalline crust of the Palaeozoic Platform, exhibiting features of the Variscan crust, reaches down to about the deep Mogilno-Ponętów-Wartkowice fault zone. The present interpretation has enabled a better recognition of both a tectonic character of this region and structural connections between deeper- and shallower-lying structures
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