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EN
During the construction of the S-3 road near Gorzów Wielkopolski, a sedimentary succession of the Eemian Interglacial and the older part of the Weichselian Glaciation were exposed. The succession, ~22 m thick, consists of lacustrine and fluvioglacial deposits. Lake sediments, mainly calcareous gyttja with peat intercalations, represent the infills of two palaeolakes. The almost complete skeleton of a forest rhinoceros, Stephanorhinus kirchbergensis, and a bone of the fallow deer Dama dama were found in the older lake deposits. Mollusc shells were numerous in both lake sequences, analysis of which revealed two types of assemblage, representing the coastal, littoral zone of a shallow lake with a muddy bottom. The sequence of mollusc communities observed in vertical succession allowed reconstruction of environmental changes during deposition. Several hydrological changes have been recognized within the palaeolake, especially water level fluctuations probably due to climate change.
EN
By comparison with the Lower Cretaceous of central and SE Poland, that of NW Poland (the Pomeranian, Szczecin, and Mogilno-Łódź troughs) has scarce biostratigraphic data. But, despite the lack of Lower Cretaceous exposure in the NW Polish Lowlands, borehole data, including borehole-cores and geophysical logs, allow analysis of complete successions. We refine the stratigraphic units using parallel studies of ammonites, microfauna and calcareous nannoplankton collected from the same intervals, and by correlating age-defined intervals with geophysical logs. Ostracod zones F to A are documented by the presence of ostracod assemblages representing the interval between the Upper Tithonian (ostracod zone F) and the lower part of the Upper Berriasian (ostracod zones E to A). The fragmentary and poorly preserved ammonites allowed only for distinguishing the uppermost Middle and Upper Berriasian (Ryazanian), while the informal subdivisions from the central part of the basin could not be identified unequivocally. Nannoplankton recognized in the succession analysed was very rare due to shallow marine facies of the strata. Only one nannoplankton zone was recognized in the lower part of the succession studied: the CC2 Stradneria crenulata Zone (uppermost Middle and Upper Berriasian and lowermost Valanginian). An additional study only on nannoplankton enabled recognition of certain boreal taxa typical of the BC2 zone of the Uppermost Riazanian. Valaginian ammonites occur in core material located closer to the central part of the trough. Some planktonic foraminiferal species indicate the Lower Aptian. Some Upper Cretaceous nannoplankton zones were also recognized: the CC9 Eiffellithus turriseiffeli (Uppermost Albian to Lower Cenomanian) and UC0, UC1-2 and UC3 zones which correspond to the Upper Albian and Lower as well as Middle Cenomanian. The sequence stratigraphic interpretation was based on geophysical logs with the application of gamma-ray, neutron-gamma, spontaneous potential and resistivity logging, as well as caliper logging. These studies allowed recognition and correlation of sedimentary sequences within the part of the sedimentary basin analysed, characterized by a similar cyclic pattern of geological phenomena described using depositional sequences as in the central and SE part of the Polish Basin. Third-order depositional sequences with maximum flooding surfaces were distinguished. Effective correlation of depositional cycles with biostratigraphy and with the global sea level curve was demonstrated for several boundaries, confirming the applicability of this method for the Polish part of the the Central-European Basin. Other boundaries recognized that are not correlatable and shifted relative to Haq’s curve may reflect autogenous factors (e.g., local tectonics) overlapping with the global changes controlled by allogenic processes.
EN
Erthwork during rebuilding of the S3 route in Gorzów Wielkopolski exposed sediments of a palaeolake. The thickness of the sediment complex reaches 11 m. Two gyttja layers are separated by peats and fluvial sands and muds. The sequence reflects a multiphase development of the lake. Lacustrine sediments overlie Odranian (Saalian) (MOIS 6) glaciofluvial deposits and are covered by Vistulian glacial sediments (MOIS 2). At present, the stratigraphic position of the palaeolake is dated to the Eemian (MOIS 5e), with a probable continuation of the deposition into the early Vistulian (MOIS 5d-4). Rhinoceros bones (more than 100 pieces), including a skull with 24 well-preserved teeth, were discovered in the lower part of the palaeolake sediments. The preliminary expertise report, based mainly on the teeth analysis, allows assigning the rhinoceros remains into the genus Stephanorhinus. The finding of so many pieces of the skeleton of Stephanorhinus sp. in situ is unique on the scale of European scale. Apart from the rhinoceros remains, a single metacarpal bone of fallow deer (Dama dama) was found in the site. This is the first record of extant fallow deer in the Pleistocene of Poland. The palaeolake sediments were sampled and multidisciplinary research is planned to reconstruct the history of the development of this basin. The relationship between the rhinoceros andfallow deer remains with the palaeoenvironment will make it possible to ascertain the conditions in which those animals lived at higher latitudes during the Eemian Interglacial.
EN
Samples collected from Late Pleistocene varved clays of the Vistulian (Weichselian) glaciation exposed at Lębork and Złocieniec (Gardno and Pomeranian phases, respectively) yielded palynological contents that are related to the different lithologies composing the varves. The dark-coloured clay units contain very small amounts of palynological material. The lighter-coloured, much thicker coarser units yielded large amounts of organic particles consisting of predominantly palynodebris of terrestrial plants, sporomorphs and aquatic palynomorphs. The latter include fresh-water and marine phytoplankton. All particles were presumably washed out from the pre-Quaternary basement or from erratic material. This is indicated by the dinoflagellate-cyst assemblages, which represent Cretaceous and Palaeogene taxa. The large amounts of organic particles in the light-coloured layers indicate high-energy meltwaters streams, which washed them out, transported them and deposited them in ice-dammed lakes. The barren layers and those with lower amounts of organic particles were deposited during calm, presumably winter, periods, when the energy of the meltwater streams was much lower.
EN
Thermal waters (61°C) occurring in the Lower Jurassic reservoirs in the Pyrzyce region (approx. 1600 m b.s.l.) are used mainly in heating plant and their chemical composition allow to apply them in balneology and recreation. In the summer time in the Pyrzyce plant only the geothermal waters are used. In the autumn-winter season, when higher temperatures of water for municipal network are needed, the system is supported by absorption heat pumps. Usage of geothermal waters in the Pyrzyce municipal heat system eliminated small carbon boilers and reduced considerable emission of harmful substance to atmosphere.
6
EN
From the beginning of geological investigations of the Polish Lowlands both the geological and the regional tectonic units were used simultaneously. The Szczecin-Gorzów Synclinorium should be distinguished in terms of tectono-structural rules. The Gorzów Block - as a geological unit - is defined on the basis of extent and differentiation of the Upper Cretaceous thickness or by distribution of local structures (mainly halotectonic and halokinetic ones) developed in the Zechstein-Mesozoic complex. Basement in the Gorzów Block area is uplifted in its consolidated part and also the top of Moho is elevated. Both uplifts are well correlated with the Permian-Mesozoic palaeogeothermal anomaly. The Gorzów Block incorporates also the north-western part of Wolsztyn Ridge which was active during the Permian-Mesozoic time. In the early Rotliegend time this area was characterized by volcanic activity. In the late Rotliegend it was a source for clastics deposited around the Wolsztyn Ridge. Also the carbonate platform facies of the Main Dolomite (Ca2) is associated with this uplifted area. The mentioned region is situated in the distal part of asymmetric, Polish rift basin. Development of basin analysis - as an interdisciplinary domain of the Earth Sciences - indicates the need of applying various geological units, adequate to the considering problem. Modern research methods in geology (computerization, GIS) enable the data bases creation for individual geological units necessary for study of their origin and evolution up to their present geological pattern.
7
PL
Walory turystyczne stanowią elementy środowiska przyrodniczego lub kulturowego, które decydują o atrakcyjności terenu, determinują aspekt poznawczy potencjalnego turysty, są uwzględniane w planach zagospodarowania przestrzennego i ochronie przyrody. O walorach turystycznych dorzecza Parsęty decyduje m.in. zróżnicowana struktura krajobrazu młodoglacjalnego. Charakterystycznym elementem środowiska przyrodniczego tego terenu jest sieć dolinna złożona z szeregu poligenetycznych obniżeń odziedziczonych po cyklu glacjalnym i peryglacjalnym. Najmłodszą część sieci drenażu stanowią dolinki erozyjno-denudacyjne i nisze źródliskowe. Elementy sieci dolinnej są silnie powiązane z pozostałymi składnikami środowiska przyrodniczego i decydują o georóżnorodności krajobrazu młodoglacjalnego. Walory krajobrazowe sieci dolinnej oraz uznanie części dolin jako obiektów ważnych w europejskiej sieci ekologicznej Natura 2000 wskazują na możliwości turystycznego wykorzystania tych form hydromorfologicznych.
EN
Tourist assets are a set of elements of the natural or cultural environment of an area that decide about its attractiveness, have a cognitive aspect for a potential tourist, and are considered in plans of spatial development and environmental protection. Among the tourist assets of Parsęta basin are a variety of valley landscapes. A characteristic element of the natural environment of this region is a valley network consisting of several polygenetic depressions left by the glacial-periglacial cycle. The youngest sections of this drainage network are erosiondenudation valleys and headwater alcoves. Elements of valley landscapes are closely connected with the remaining components of the natural environment and are an important factor determining the geodiversity of the postglacial landscape. A well-thought-out conception of their development and accessibility, including also damage-preventing measures, can certainly enrich the region’s tourist offer.
EN
Evolution of the Pomeranian Basin (NW Poland) dur ing the Devonian saw the development of a characteristic siliciclastic and mixed siliciclastic-carbonate marginal marine-to-open marine carbonate sedimentary succession. This was controlled via proximity of the land areas representing uplifted parts of the East European Craton (EEC): the Fennoscandian High extending in the north, and the Mazury–Belarus High, situated in the east. The depositional history of the Pomeranian Basin began not earlier than at the end of the Emsian or possibly in the Eifelian, after a long break spanning the Lochkovian, Pragian and much of the Emsian when the area was subjected to erosion. Sedimentation started in the north eastern part with marginal-marine clastic deposits with local evaporites which are dated as uppermost Emsian?–Eifelian, passing upwards into lower–middle Givetian marginal-marine siliciclastic and carbon ate de posits; these are followed by upper Givetian marginal-marine siliciclastic rocks. In the south western part of the area, the Devonian succession started with marginal-marine carbonates and siliciclastics which belong to the upper most Emsian?–Eifelian, followed by lower and middle Givetian carbonates, passing upwards into upper Givetian marginal-marine siliciclastics. During the Late Devonian the Pomeranian Basin underwent evolution from a marginal-marine in the earliest Frasnian, through carbonate ramp or platform/shelf basin settings during the rest of the Frasnian and early Famennian, up to a reappearance of shallow subtidal and marginal-marine environments in late Famennian time. At the end of the Famennian an open shelf environment became prevalent almost over the whole area and continued up to the Mid Tournaisian. The lateral relation ships of the lithofacies during the Givetian, Frasnian and Famennian are portrayed on 11 maps, showing relatively short time-intervals, selected to depict the most sigificant environmental changes. Transgressive-re gres sive depositional cy cles ob served in the Pom er a nian Ba sin seem to have been strongly con trolled by sea level vari a tions, prob a bly of eustatic na ture; how ever, tec tonic ac tiv ity of some struc tural el e ments lo cally mod i fied the sed i men tary re cord.
9
Content available remote Podłoże magnetyczne w pomorskim segmencie strefy szwu transeuropejskiego
PL
Interpretacja danych magnetycznych w powiązaniu z danymi grawimetrycznymi oraz sejsmicznymi miała na celu uzyskanie nowych informacji o strukturze podłoża magnetycznego w pomorskim segmencie strefy TESZ w NW Polsce. Zidentyfikowano cztery prowincje magnetyczne (A, B’, B” i C), o zróżnicowanym charakterze magnetycznym, rozdzielone strefami gradientowymi (magnetycznymi lineamentami) Koszalin–Szczecinek–Bydgoszcz–Toruń (KSBT), Szczecin–Stargard Szczeciński–Inowrocław (SSPI) i Słubice–Leszno (SL). Wydzielone prowincje odpowiadają blokom strukturalnym podłoża, a lineamenty magnetyczne są związane z głównymi strefami uskokowymi. Krystaliczna skorupa prowincji magnetycznej B” prawdopodobnie wywodzi się ze wschodniej Awalonii, natomiast w obszarze B’ może stanowić klin krystalicznej skorupy platformy prekambryjskiej wbijający się w skorupę wschodniej Awalonii. Nie da się jednak wykluczyć wersji, że jest to skorupa proksymalnego lub egzotycznego terranu, łuku wyspowego albo pozostałość po pryźmie akrecyjnej. Na podstawie analizy danych magnetycznych zaproponowano tektoniczny model kaledońskiej kolizji między kontynentami wschodnią Awalonią i Baltiką, z przypuszczalnym udziałem dodatkowego bloku skorupy o niejasnym pochodzeniu. W tym modelu zamknięcie morza Tornquista miało miejsce wzdłuż zapadającej ku NE strefy subdukcji, występującej w strefie TESZ.
EN
Magnetic data has been interpreted in conjunction with gravity data and seismic reflection and refraction profiles to provide new information about the magnetic basement structure in the Pomeranian segment of the TESZ in NW Poland. Four distinct magnetic provinces (A, B', B" and C) with significantly different magnetic character and separated by the gradient zones of Koszalin-Szczecinek-Bydgoszcz-Toruń (KSBT), Szczecin-Stargard Szcz.-Piła-Inowrocław (SSPI) and Słubice-Lesmo (SL), were recognized. These provinces are related to individual structural blocks and the identified magnetic lineaments reflect majortectonic discontinuities. The crystalline crust of magnetic province B" is of presumably the Eastern Avalonian origin whereas a crustal wedge of the EEC, indenting the Eastern Avalonian crust, may occur in magnetic province B'. However, another possibility cannot be precluded that this is a proximal or exotic terrane crust, island arc crust or a relic of an accretionary prism. The analysis of the magnetic data resulted in a tectonic model of the Caledonian collision of Eastern Avalonia and Baltica with the presumed participation of an additional crustal block of an unclear provenance. In this model the closure ofthe Tornquist Sea took place along a subduction zone occurring in the TESZ and dipping towards the northeast.
PL
Przeprowadzono identyfikację lokalnych systemów krążenia wód podziemnych na obszarze Międzyrzecza Warty i Noteci (1912 km2), które stanowi największą pod względem powierzchni strefę wydm śródlądowych w Wielkopolsce. Dla wód poziomu gruntowego o różnym stopniu połączenia z siecią hydrograficzną, określono warunki zasilania i drenażu oraz dokonano oceny składowych bilansu ich przepływu. Wskazano strefy, gdzie mogą formować się systemy wód podziemnych zagłębień bezodpływowych chłonnych i ewapotranspiracyjnych (retencyjnych), w granicach których wymiana wód odbywa się poprzez infiltrację, wsiąkanie lub parowanie. W analizie wykorzystano cyfrową bazę danych Mapy Hydrograficznej Polski w skali 1 : 50 000 oraz wyniki modelowania matematycznego filtracji wód podziemnych przeprowadzonego w odniesieniu do warunków przeciętnych z okresu wielolecia. Założono, że elementem ograniczającym efektywne zasilanie wód podziemnych na terenach wydmowych jest znaczna miąższość utworów piaszczystych (do 30-50 m) i głębokie występowanie zwierciadła wód podziemnych. Wskazano funkcjonowanie stref aktywnych w formowaniu odpływu powierzchniowego oraz bezodpływowych powierzchniowo, szczególnie typu chłonnego (20% powierzchni), które stanowić mogą obszary lokalnie wzmożonego zasilania infiltracyjnego płytkich wód podziemnych i kształtowania tą drogą odpływu podziemnego ze zlewni. Stwierdzono, że doliny Warty i Noteci, jako główne osie drenażu, wymuszają silny odpływ wód podziemnych z centralnej części międzyrzecza, czego efektem jest brak sieci rzecznej.
EN
The local groundwater-circulation systems in the Warta-Noteć Interfluve (1912 km2) are identified; this interfluve is the largest area covered with inland dunes in the Wielkopolska Lowland. The alimentation and drainage of the groundwater, which depend to varying degrees of the surficial hydrographic network, are described, and the contributions by the various components determining the flow balance are estimated. The zones are indicated where basins could develop without external drainage, so that all inflowing water is absorbed and can escape (partly) only be evapotranspiration, and within which water is exchanged exclusively through infiltration and evaporation. A digital database of the 1 : 50,000 Hydrographic Map of Poland, in combination with the results of a mathematical model regarding the groundwater infiltration over time was used for the purpose. It is assumed that the considerable thickness of the sands (up to 30-50 m) and the deep position of the groundwater 198 Renata Graf are responsible for the limited groundwater alimentation in the dune areas. It is shown that zones with and without surface runoff exist; the latter are predominantly (20% by surface area) of the absorbent type and are partly areas of locally enhanced infiltration of groundwater, partly areas with subsurface runoff. It is emphasized that the Warta and Noteć valleys, being the main drainage routes, force a strong groundwater runoff from the central part of the interfluve, where no river network is present.
EN
Chemical composition of saline groundwaters occurring in the Mesozoic deposits of NW Poland, based on 285 archival chemical analyses from 113 deep boreholes, shows much similarity within particular aquifers. These are mostly chloride-sodium waters. Chloride-sodium-calcium waters predominate only within the Lower Triassic aquifer. Chloride-sodium-magnesium waters appear only at isolated locations. All the waters studied are typical of a high mineralization (TDS), the latter increases with the aquifer depth up to a maximum of 328 g/dm3 (Objezierze IG-1 well). The TDS of these brines, measured systematically over the last 40 years at production wells in the health resorts Kołobrzeg, Kamień Pomorski, Świnoujście and Połczyn Zdrój, is nearly constant and directly proportional to the concentration of Cl– ion. The brines in Mesozoic aquifers of NW Poland are polygenetic. Their main components are fossil seawater and meteoric water. Holocene infiltration water is a local admixture in the upper part of the Mesozoic succession only. The hydrochemical indicators (Br–:J–, Cl–:J–, Cl–:Br–, Ca2+:Sr2+, rNa+:rCl–) and the isotope ratios of oxygen, hydrogen and strontium suggest that the salinity of waters in the Mesozoic deposits is related to their marine origin and, to a lesser extent, to the dissolution of Zechstein and Triassic salts. Dissolution of Zechstein salts could occur in contact zones with groundwaters within the Mesozoic until the chemical balance between them has been established. Such contacts are currently observed at base of the Lower Triassic rock as well as in 18 salt structures piercing the Triassic aquifers. Brines within the Triassic rock contain an admixture of residual (evaporite-related) liquids associated with the Zechstein and Triassic salt series. The saline waters within the Mesozoic rock complex are under pressure, which enables their upward migration through a system of fractures and faults towards the Cenozoic aquifers. This process is most intense in hydrogeological windows developed in areas of erosional reduction of the overlying Oligocene clays on uplifted tectonic blocks and salt-cored anticlines. The extent of increased groundwater salinity zones in Cenozoic deposits depends on flow directions in the active circulation zones. Therefore, these salinity zones, which occupy 33% of the study area, do not always coincide with the zones of brine ascension. The ascent of saline water is hazardous to the quality of Major Groundwater Reservoirs (MGR). This concerns the MGRs of Uznam (101) and Wolin islands (102), Rościno (103) and Dębno (134), as well as large municipal groundwater intakes, such as those in Świnoujście (“Wydrzany”), Wolin, Trzebiatów, Gryfice, Kołobrzeg (“Rościęcino” and “Bogucino”), Koszalin, Goleniów, Nowogard, Gryfino (“Tywa” and “Dolna Odra”), Krzypnica, Stargard Szczeciński, Choszczno, Wałcz and Czarnków locations.
EN
The salinization of Cenozoic aquifers caused by brines ascending from the Mesozoic was described on the basis of results of 7747 archival chemical analyses. The zones of confirmed aquifer salinization, defined by chloride concentration exceeding 60 mg/dm^3 and 70 mg/dm^3 (upper limits of hydrochemic background values), within the Pleistocene and Paleogene, Miocene and Pliocene usable groundwater aquifers respectively, occupy an area of 8600 km^2 (33 % of the study area), whilst the zones of potential salinization hazard extend on further 4900 km^2 (19%). The groundwater salinization zones are mostly connected with the uplifted tectonic blocks, salt anticlines and fault zones, the structures allowing upwards directed migration of the Mesozoic brines into the Cenozoic useful aquifers. The salinization development is generally controlled by the flow directions within the active circulation zone and causes migration of brines under pressure along the tectonically produced pathways. The salinity increase affecting groundwater in the Cenozoic aquifers does not result from the recent leaching of the Zechstein salt bod-ies, as they are mostly isolated from the groundwater active circulation system. The ascending diluted brines constitute a potential threat to 4 (Uznam–101 and Wolin–102, Rooecino–103, Dębno–134) from among 20 Major Groundwater Reservoirs and to 17 from among 31 main municipal groundwater intakes (total well discharge >100 m^3/h).
PL
Modelowanie reologii litosfery przeprowadzono wzdłuż przekroju sejsmicznego LT-7. Przecina on w poprzek strefę szwu transeuropejskiego (TESZ), cechującą się znaczną oboczną zmiennością struktury skorupy ziemskiej oraz reżimu termicznego. W zależności od warunków fizycznych oraz składu mineralnego deformowanego ośrodka skalnego, przypisywano mu styl deformacji kruchy lub podatny. Przyjęto, że wielkość naprężeń dyferencjalnych w warstwach kruchych ograniczona jest tarciem na powierzchniach uskoków, natomiast w warstwach podatnych oporem pełźnięcia dyslokacyjnego sieci krystalicznej. Jako dane do przeprowadzonych analiz wykorzystano sejsmiczny model prędkościowy wzdłuż refrakcyjnego przekroju LT-7, rozkład gęstości powierzchniowego strumienia cieplnego wzdłuż przekroju, a także, przez analogię do obszarów sąsiednich, miąższość mechanicznej litosfery oraz produkcję ciepła radiogenicznego. Dla pozostałych parametrów modelowania przyjęto wartości standardowe z literatury. Poszczególnym warstwom modelu sejsmicznego przypisano zgeneralizowany skład mineralny oraz stałe materiałowe, charakteryzujące deformacje podatne. W pierwszej kolejności wykonano profile temperaturowe litosfery, które następnie wykorzystano w modelach reologicznych. Jednowymiarowe modelowanie dla każdego profilu przeprowadzono dla wariantów zmiennych parametrów termicznych, zmierzając do uzyskania płynności zmian strumienia cieplnego z płaszcza i miąższości termicznej litosfery między profilami. Wyliczone wartości strumienia cieplnego z płaszcza są zmienne od 20 mW/m2 na kartonie wschodnioeuropejskim, przez 20-35 mW/m2 w strefie TESZ (z maksymalnymi wartościami w jej SW części), do 25-30 mW/m2 na platformie waryscyjskiej w Niemczech. Miąższość termicznej litosfery w poszczególnych, powyżej wymienionych strefach, wyniosła odpowiednio: 170-200 km, 90-160 km oraz 110-140 km. Główną cechą analizowanego profilu reologicznego, jest osłabienie litosfery w jego centralnej części, tj. na skraju platformy paleozoicznej i w sąsiadującej z nią części TESZ. Strefa tego osłabienia pokrywa się z obszarem podwyższonego strumienia cieplnego. W jej obrębie niemal zanika wytrzymałość górnego płaszcza. Wzdłuż całej pozakratonicznej części profilu, w obrębie środkowej i dolnej skorupy wyraźne zaznacza się strefa osłabienia, stanowiąca warstwę o miąższości ok. 20 km. Osłabienie to powoduje mechaniczne rozdzielenie górnej skorupy i górnego płaszcza. Jedynie na kratonie wschodnioeuropejskim poszczególne warstwy litosfery są mechanicznie spojone ze sobą. Obliczona całkowita wytrzymałość litosfery w kontrakcji zmienia się od 30-50 ×1012 N/m na kartonie wschodnioeuropejskim, przez 15-25 ×1012 N/m w strefie TTZ oraz poniżej 5 ×1012 N/m w SW części strefy TESZ, do 5-15 ×1012 N/m w na platformie waryscyjskiej. Analiza wrażliwości modelu wykazała, że zmienność parametrów termicznych w realistycznych granicach ma znaczny wpływ na wytrzymałość litosfery, lecz nie rzutuje na jej generalne rozwarstwienie reologiczne. Dodatkowo stwierdzono, że niezależne określenie miąższości mechanicznej litosfery jest podstawowym warunkiem sporządzenia wiarygodnego modelu reologicznego dla omawianego obszaru.
EN
The present study concerns rheological structure of the Trans-European Suture Zone (TESZ) and neighbouring tectonic units in Poland and SE Germany, along the LT-7 deep seismic sounding (DSS) profile. The SW-NE trending transect, 560 km in length, crosses the Variscan platform (VP - without its TESZ segment), part of the TESZ composed of external Variscan orogen and its foreland (VSZ- Variscan Suture zone), the Teisseire-Tornquist Zone (TTZ), and terminates on the western slope of the East European Craton (EEC; fig. 1). Both complex crustal structure and significant lateral changes in surface heat flow along the LT-7 profile make it an attractive object for study of the rheological differentiation of lithosphere. 1-D temperature and rheological modelling was performed for 10 sites located along the LT-7 profile. The most important and best-constrained input data are seismic wave velocity structure (fig. 2) and surface heat flow density (fig. 3). A simplified petrological model (fig. 4) based on P-wave velocity differentiation has been founded on a concept of quartz/diorite/diabase/pyroxenite/olivine layering of the lithosphere. Lithosphere temperature profiles for each site were derived by analytical solutions of Fourier 's law, applied to two layer crust model with the mantle being infinite half-space. For analysed sites, for each petrological defined layer constant value of radioactive heat production and thermal conductivity were assumed (fig. 4). For calculations of strength envelopes, Byerlee 'sfrictional law, for brittle layers and powerlaw creep for ductile layers were used. An assumption of wet rheology was generally applied. In order to narrow the range of possible solutions, the rheological models were to fulfill three principal conditions: (1) Thickness of thermal lithosphere should laterally vary from 70 km to 200 km (constrained by extrapolated seismological data). (2) Mantle heat flow and lithospheric thickness should change smoothly from site to site. (3) Cumulative strength of the lithosphere for the strain rate 10^-16 s^-1 should always be higher than 2-10^12 N/m (neotectonic quiescent of the analysed area indicates that the lithosphere sustains plate boundary forces). In spite of poor control on some input data and no restrictive principal conditions, possible solutions of the model fall into a narrow range of options. Performed modelling allowed to estimate cumulative lithospheric strength along the profile (fig. 5a), which changes of more than an order of magnitudefrom 30-50 *10^12 N/m at the edge of the EEC, through 15-25 -10^12 N/m in the TTZ and less then 5-10n N/m in the VSZ, to J 15-10^12 N/m in the VP. Calculated mantle heat flow (fig. 5b) varies in a range from 20 m W/m2 in the EEC, through 20-35 m W/m2 in I lie TESZ (with maximum values at its SW boundary), to 25-30 m W/m2 in the VP. For the same segments of the profile thickness of thermal lithosphere estimated on 170-200km, 90-160 km and 110-140 km (fig. 5c), respectively. Additionally, thermal modelling led also to some constraints on the radioactive heat production in the upper crust. The first-order feature of the obtained rheological section (llg. Sc) is that the transition zone from the VSZ to the VP is extremely weak. As evidenced from coincidence with high surface and manile heat /low, observed mechanical weakening is thermally controlled. The second significant outcome of the model is the existence of i hfological layering of the lithosphere. Apart of the EEC, only two strong layers were recognised, namely uppermost crust and uppermost manile. These layers are separated by extremely weak lower crust, more than 20 km thick. For the lithosphere of the EEC three or lour strong layers were recognised. Some of them might be mechanically welded to each other. Sensitivity of the rheological model to variability of radioactive heat production and surface heat flow has been also examined (fig. 6). Changes of these parameters in realis-lu range lead to significant differences in the shape of strength envelopes and thickness of thermal lithosphere. This leads to the con-i luston, that any independent control on lithospheric thickness would be crucial for improving quality of rheological model.
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Content available remote Modelowanie grawimetryczne i magnetyczne wzdłuż profilu LT-7
PL
Wspólne modelowanie danych grawimetrycznych i magnetycznych zostało wykonane wzdłuż refrakcyjnego i szerokokątowego refleksyjnego profilu LT-7, który przecina strefę szwu transeuropejskiego w NW Polsce. Na podstawie wyników modelowania grawimetrycznego stwierdzono, że budowa skorupy jest bardziej skomplikowana niż to wynika z modelu prędkościowego. Dane grawimetryczne wskazują na obecność w górnej skorupie intruzji o wysokiej gęstości oraz złożonej strefy przejściowej między skorupą a górnym płaszczem w rejonie transeuropejskiej strefy szwowej. Dane magnetyczne w rejonie położonym na SW od linii Teisseyre’a - Tornquista zostały zinterpretowane w postaci kontaktu odwrotnie namagnesowanej dolnej skorupy platformy paleozoicznej z normalnie namagnesowanym blokiem dolnej skorupy występującym w strefie szwu transeuropejskiego. Na podstawie wyników modelowania magnetycznego i grawimetrycznego ten kontakt jest nachylony ku NE. Może on wskazywać na szew tektoniczny utworzony w czasie kaledońskiej kolizji Wschodniej Avalonii i Baltiki, w której mógł brać udział dodatkowy blok skorupy niewiadomego pochodzenia. Ten blok może reprezentować klin skorupy Baltiki, skorupę terranu proksymalnego lub egzotycznego, albo skorupę łuku wyspowego.
EN
Simultaneous gravity and magnetic data modelling has been performed along refraction and wide-angle reflection profile LT-7 crossing the Trans-European Suture Zone in NW Poland. The gravity modelling indicates the crust structure is more complicated than revealed by velocity model. Gravity data indicate the presence of a high density body in the upper crust, and a complex transition zone between crust and upper mantle occuring in the Trans-European Suture Zone. Magnetic data SWofthe Teisseyre-Tornquist Line has been interpreted in terms of complex contact reversely magnetized lower crust of Palaeozoic Platform and normally magnetized lower crustal block occuring in the Trans-European Suture Zone. On the basis of magnetic and gravity modelling this contact dips to NE. It may indicate a suture formed due to the Caledonian collision of Eastern Avalonia and Baltica with the presumed participation of an additional crustal block of an unclear provenance. The latter may represent a wedge of the EEC crust indenting the Palaeozoic Platform crust (Eastern Avalonia?). However, this could possibly be a crust of a proximal or exotic terrane or an island arc crust.
EN
Five local miospore zones, six subzones and two assemblages are distinguished for the Frasnian to lower Tournaisian deposits in the Kołobrzeg region (western Pomerania): assemblage I, Membrabaculisporis radiatus-Tholisporites densus (RD), Membrabaculisporis radiatus-Cymbosporites boafeticus (RB), Lagenoisporites immensus-Diducites poljessicus (IP) Zone, assemblage II, Tumulispora rarituberculata (Ra) and Convolutispora major (Ma) Zone. The first three biozones and the two assemblages are new in this region. The local miospores zones distinguished in western Pomerania are correlated with the European standard miospore and conodont zonations. Two new miospore species and one new variety are described, two species is emended.
PL
Sekwencję 11 geologicznych map ścięcia na poziomach od 0 do 200 m p.p.m., w sekcjach co 20 m, wykorzystano do prezentacji budowy kompleksu kenozoicznego. Mapy te ilustrują wzajemne relacje przestrzenne między utworami mezozoiku a osadami trzeciorzędu i czwartorzędu w obrębie analizowanych elementów i jednostek strukturalnych. Na 11 poziomach ścięcia widać wyraźny związek między układem jednostek oraz elementów strukturalnych permo-mezozoiku i wewnętrzną organizacją ich pokrywy kenozoicznej. Przestrzenne zróżnicowanie ukształtowania powierzchni podkenozoicznej i powierzchni podczwartorzędowej oraz miąższość osadów trzeciorzędu i czwartorzędu są dostosowane do budowy tektonicznej permo-mezozoiku. Czytelność zapisu tych zależności na mapach ścięcia poziomego sprawia, że są one doskonałym narzędziem do obserwacji skutków procesów neotektonicznych.
EN
11 geologic maps ofcutting on levels from 0 to 200 m. b.s.L, in 20 m interval, were used for presentation of Cainozoic complex internal structure. Decribed maps present spatial relations between Mesozoic, Tertiary and Quaternary deposits in construction of analysed units and local tectonic elements. Maps of 11 cutting levels show a very distinct connection between tectonic elements and internal construction of their Cainozoic cover. Spatial differentiation pattern ofsub-Cainozoic and sub-Quaternary surfaces relief and thickness of Tertiary and Quaternary deposits are adapted to tectonic framework ofPermo-Mesozoic complex. Distinct record of this adaptation which is visible on maps of geological cutting allows for using them as an excelent tool for neotectonic processes analysis.
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