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EN
Progress in geological, geophysical and drilling sciences during the past 30 years has introduced to hydrocarbon exploration the concept of petroleum system, understood as an analysis of the factors necessary forformation and preservation of oil and natural gas deposits. Thefinal evaluation ofpetroleum system is the product of allfactors involved in the formation of hydrocarbon accumulations, which must be preserved proper chronology of events in the geological space. Such interdependences build often synergistic or antagonistic configurations. These configurations are called critical elements of the petroleum system. Reliable and comprehensive analysis of critical elements ofpetroleum system in sedimentary basins in Poland lets identify potential new areas of hydrocarbon exploration. In this context, a particularly promising area is the petroleum system of the Pita Claystone Formation (central part of the Polish Rotliegend Basin) and deep “Carpathians” with their palaeo-mesozoic basement and deeper part of the Carpathian Foredeep.
2
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.
EN
The Polish part of the Baltic region is located within the contact zone between two large geological units: the Precambrian platform and the Paleozoic platform. It comprises the Polish sector of the southern Baltic Sea and the adjacent onshore part of Northern Poland (Western and Eastern Pomerania). The fundamental geological pattern is defined by the Teisseyre-Tornquist Zone, separating the East European Craton from the Paleozoic platform. As a result of exploration activity in the onshore Pomerania region, four oil fields in Cambrian sandstones, seven gas fields in Carboniferous sandstones, six gas fields in Rotliegend sandstones, and eleven oil fields within the Zechstein Main Dolomite horizon have been discovered. The petroleum play of the southern Baltic Sea region and adjacent areas must be considered separately for Eastern and Western Pomerania. In the Peribaltic Syneclise we can only take into consideration organic matter appearing in lower Paleozoic rocks but their geothermal history refers to the period from the Vendian up to the recent. The present extent of the "oil window" in the Upper Cambrian rocks is mainly restricted to the offshore area. Reservoir properties of the "gas window" Cambrian rocks are rather low due to intensive diagenetic processes. Acquisition of gas should be possible by processes of hydraulic stimulation (tight gas). Lower Paleozoic rocks rich in organic matter (Ordovician and Silurian), especially in the border zone of the EEC (Ro >>gt; 1.3%), could be an area of unconventional gas fields (shale gas). The Western Pomerania petroleum play shows two separate source rocks units. The older one embraces Carboniferous deposits with organic matter of terrestrial origin and generated gases accumulated in the Rotliegend and Carboniferous traps. The second petroleum system is located within the carbonates of the Zechstein Main Dolomite (Ca2). This is a closed system, meaning that the source rocks are at the same time the reservoirs sealed by Zechstein evaporates. Hitherto discovered hydrocarbon deposits in the Polish part of the Baltic region have confirmed good perspectives regarding oil and gas hydrocarbon zones. New, conventional and unconventional discoveries remain possible.
5
Content available Regionalizacja tektoniczna Polski-Niż Polski
EN
Presented paper is a contribution to discussion about the tectonic regionalization in Poland. The Polish Lowlands, located between the Baltic shore and the highlands of the southern and central Poland, is the area discussed here. In this region mainly the Quaternary and the Neogene deposits with thickness rarely over 300 m are exposed. On the sub-Cenozoic surface occur mainly Cretaceous, Jurassic and Triassic rocks. Structural forms of the Polish Lowlands are directly associated with the Permian-Mesozoic Polish Basin inverted at the beginning of Cenozoic time. It is worthwhile indicating here that not only the Polish Trough was inverted but also the distal part of this basin, distinguished now as the Fore-Sudetic Monocline. Subdivision of the Polish Lowlands into tectonic units on the sub-Cenozoic surface was shown on Fig. 1. In the mid-Polish area antyclinorium belts of north-west to south-east orientation are located. The basement of the Polish Basin is built of the pre-Permian deposits, tectonized during pre-Alpine phases. To analyze the geology of Poland in the sub-Permian architecture the proper tectonic map (Fig. 2) is required with only the units of first order marked. Debate on tectonics of Poland requires also a map of basement consolidation units (Fig. 3). Indispensable completion of the presented maps is a geological cross-section of the Polish Lowlands (Fig. 4). It is clear that tectonic regionalization of Poland (with special attention to the Polish Lowlands) should be demonstrated on the three basic maps here presented. Spatial (both horizontal and vertical) relations between tectonic units should be considered in the light of sedimentary basin analysis, i.e., searching processes and stages of the structural evolution which essentially contributed to the recent tectonic diversification in regional geology.
EN
Discussion on the tectonic regional subdivision of Poland is a good opportunity to show a range of geological information of each tectonic unit and to emphasize the necessity of improvement of geological tectonic classifications, application of which in the geological databases is essential for correct usage of data collected. A good example is a geological and geophysical database PITAKA developed in the Polish Oil and Gas Company from 1987. Actually the PITAKA database contains data from 3191 boreholes which drilled Permian and younger deposits and from 4555 boreholes pierced into the older rocks. This paper presents location of 2D and 3D seismic studies done in digital technology from its introduction in Poland in 1973. In the Polish Lowlands area the Fore-Sudetic Monocline is the best geologically recognized region. The Pomeranian Anticlinorium and the Szczecin-Gorzów Synclinorium are relatively well documented. Numerous boreholes and seismic sections in those areas are associated with intensity of exploration of raw material deposits such as hydrocarbons, coal, copper, zinc and lead, sulfur and salts. Until now the PITAKA database does not contain all drilling data from Poland but it is constantly extended and supplemented.
EN
Poland has the limited gas and oil resources. Main hydrocarbons supplies are delivered to Poland mostly from Russia by oil and gas pipelines. Very large length of these pipelines as well as the local considerable wearing of devices induces the necessity of reserves storage. Geological conditions in Poland and a considerable quantity of exhausted gas deposits enabling in nearest years to the construction of underground gas storages (UGS) suggest the new investments in this sector of petroleum industry. Capacity amount of present active UGS is 1.58 x 10exp.9 mexp.3 but after finalizing of storages their volume will achieve 2.8 x 10exp.9 mexp.3. Special attention is paid to the Wierzchowice UGS (the biggest one in Poland) and to caverns leaching within the Zechstein salts cavern underground gas storages (CUGS) Mogilno and Kosakowo. Reservoirs of cavern type (expensive under construction) are a very efficient, modern source of gas system supply, particularly in periods of the seasonal demand fluctuations for gas - a very high during the winter season in the central and the northern Europe. Only caverns in salts allow to store both the gas and the liquid hydrocarbons. Construction of the UGS refers mostly to exhausted gas fields, discovered and exploited by the Polish Oil and Gas Company. Experience and capital of the state company located it as a leader in Poland in the field of construction and exploitation of underground storages. Their construction has the minimum influence on the environment. Utilization of exhausted hydrocarbons deposits (often with the existing mining infrastructure) is not almost at all troublesome for a local population and the environment and it offers considerable practical and economic benefits. The economical boom in the oil and gas market during last years creates new challenges for construction and exploitation of hydrocarbons underground storages.
8
Content available Petroleum Provinces in Poland
EN
The scheme in which the Carpathians, Carpathian Foredeep and Polish Lowland are distinguished as the hydrocarbon prospective zones was used hitherto in Poland. Good geological diagnosis of Poland area enables to distinguish the petroleum provinces in terms of basin analysis (methodology). This procedure are based on an integration of multidisciplinary geological and geophysical data with into a petroleum play concept. Results of drillings and petroleum play procedures allow to predict boundaries of petroleum provinces. Effects of basin analysis with regards to the stratigraphy of hydrocarbon-bearing areas are presented in Figure 1. All these prospective areas (Fig. 1) have been matched into five independent units (Fig. 2) which could be defined as following petroleum provinces: Pomerania, Wielkopolska, Ma3opolska, Lublin and Gdansk. These petroleum provinces are only the parts of sedimentary basins the individual development of which enabled generation, migration and preservation of hydrocarbons. Location of the above mentioned petroleum provinces is also brightly reflected on the map of crustal consolidation (Fig. 3): every province in Poland has its own individual geologic history.
9
Content available Permian Basin as a main exploration target in Poland
EN
The Polish Permian Basin (PPB) is a part of the Southern Permian Basin in theWestern and the Central Europe. Results of burial and thermal analyses as well as a configuration of the Moho surface of the Polish Basin suggest the asymmetrical basin model. History of the Polish Basin reveals that the Late Permian and the Early Triassic periods represent the main rifting phase and its later development resulted from thermal relaxation. During the Late Triassic and the Jurassic time some cooling of rift heat field took place, but the turning point in thermal evolution of the Polish Basin was at the Jurassic/Cretaceous boundary when the south-western part of the Polish Basin was uplifted and intensively eroded. The knowledge on the Permian Basin in Poland is chiefly connected with petroleum exploration. The gas fields are located mainly in the Rotliegend reservoirs. The Zechstein deposits, overlying the Rotliegend, are also in the area of economic interest: hydrocarbons occurring in carbonate deposits of the Werra (Zechstein Limestone - Ca1 ) and Stassfurt (Main Dolomite - Ca2) cyclothems. Several tens gas fields have been hitherto discovered within the Rotliegend sandstones and the Zechstein limestones. Reservoirs are the clastic, terrestrial deposits of the Lower Permian and calcareous, biogenic carbonates of the Zechstein. Evaporates, mainly salts of the Werra cyclothem, are the regional sealing for the mentioned reservoirs. Natural gas accumulated in the Rotliegend sandstones and the Zechstein limestones is of the same origin: it was generated from organic matter occurred in the Carboniferous rocks and it migrated to higher places where it became concentrated within favourable structural or lithofacies conditions. High nitrogen content in the natural gas from the Polish Permian Basin is explained that nitrogen is generated from an organic matter within a sedimentary basin at higher temperatures than methane. Location of high helium concentration corresponds to the area of highest heat flow during the Late Permian, Triassic and Jurassic times, evidencing the Late Permian-Early Mesozoic rifting process. Numerous oil gas fields discovered in the Main Dolomite (Ca2) unit constitute it as one of the most important exploration target in the Polish Basin. It composes the closed hydrodynamic system sealed from the top and the bottom by evaporates. Both the source rocks and reservoirs are characteristic for this unit. Influence of the burial and thermal history of the Polish Basin on a petroleum play generation within the Main Dolomite unit is clearly visible. The previous and the present petroleum discoveries in the Polish Permian Basin, comparing to the other petroleum provinces in Poland, indicate it as a main exploration target.
PL
Eksploracja basenu lubelskiego doprowadziła do rozpoznania budowy geologicznej regionu i szczegółowego przebadania profilu geologicznego osadów paleozoicznych i mezozoicznych. Od roku 1956 wykonano ok. 240 głębokich wierceń i odkryto kilka złóż ropy naftowej i gazu ziemnego. W osadach dewońskich opróbowano około 520 interwałów (statystyka nie uwzględnia otworów wydobywczych) i w 280 przypadkach uzyskano przypływy solanek zgazowanych w ilościach nieprzemysłowych. Wykonano też około 300 opróbowań w karbonie. W około 70% przypadków nastąpił wypływ solanki zgazowanej z domieszką ropy naftowej.
EN
The western part of the Palaeozoic Baltic Basin is a potential area of petroleum exploration. Most perspective are here the Cambrian deposits because source and reservoir rocks have the best properties. On the basis of structural, subsidence and present /past thermal analysis, the modeling of hydrocarbon formation along five geological cross-sections using the PetroMod software was carried out. The spatial range of the modeled "oil window " in the Cambrian deposits is relatively narrow and runs from the Łeba Elevation through the Gdańsk Bay southwards. The Cambrian rocks in the Warmia region - adjacent to with the Kaliningrad District where Russian geologists discovered oilfields in the Cambrian deposits - are in the first phase of hydrocarbon generation. Present thermal field in Lithuania and the Kaliningrad District indicate on the existence of strong positive geothermal anomaly which probably heated up not deeply lying Palaeozoic rocks to the "oil window "phase. This optimistic circumstance permits to suppose that along the Polish side of state border, from the Warmia region eastwards, the "oil window" parameters are improved. If the other factors of the petroleum play will be affirmative, then the area of northern Warmia may produce expect new oil field discoveries.
EN
One of the petroleum play elements is to determine organic matter maturity zones. In the case of hydrocarbon exploration in the Lublin area it mainly pertains to Devonian and Carboniferous deposits. Geological knowledge of local of stratigraphy, lithology, subsidence and erosion rates enables to provide data for computer modelling. The knowledge of calibrating parameters (e.g.) present temperatures, values of the vitrinite reflectance and CAI) is here also satisfactory. Results of the computer modelling (PetroMod) made possible to prepare the map of heat flow values for the Middle to Upper Devonian and Carboniferous period. These values are very high (90-130 mW/m2) and can be comparable to the magnitude of the heat flow in rift zones. Correctness of the obtained results was confirmed by investigations on homogenization temperatures of cement inclusions in the Devonian and Carboniferous rocks. Evolution of the organic matter maturity in the Lublin area obtained as result of computer-aided simulations (PetroMod) shows that Carboniferous stage of the basin formation was the main phase for oil and gas generation. The reorganization of the Lublin Basin into the Lublin Synclinorium which in turn became included in the Polish Basin at the Late Jurassic time did not influence crucially the hydrocarbon generation in the Devonian and Carboniferous deposits. Present distribution of the organic matter maturity zones indicates that Devonian rocks are in the most cases overmature whereas the Carboniferous ones are in the oil and gas window. The planning of further exploration should take into account also results of the hydrocarbon generation modelling in the Lublin area.
PL
Geologiczne interpretacje zdjęć satelitarnych w małej skali wykonuje się rzadko i stąd ten temat jest prawie nieobecny w literaturze naukowej. Niniejszy artykuł przedstawia geologiczną interpretację zdjęć satelitarnych metodą pokryć wielokrotnych z obszaru południowej Polski, gdzie występuje znaczne zróżnicowane genetyczne, petrologiczne i morfologiczne jednostek geologicznych. Uważamy, że obiektywność, prostota, niski koszt oraz krótki czas interpretacji zdjęć satelitarnych według proponowanej metody czyni ją przydatną w naukach geologicznych. Dane uzyskane dzięki geologicznej interpretacji zdjęć satelitarnych metodą pokryć wielokrotnych mają wartość obiektywną i umożliwiają wykonanie statystycznej oceny zależności pomiędzy różnymi zjawiskami geologicznymi i geomorfologicznymi.
EN
Geological interpretations of small-scale satellite images are scarce and this subject is almost absent in scientific publications. This paper presents the multi-coverage geological interpretation of satellite images for some areas of southern Poland, where different genetic, petrologic and morphologic units occur. We believe that objectivity, simplicity and low cost, as well as quick data elaboration of the proposed methodology makes it useful in geological sciences. The data obtained from the multi-coverage geological interpretation of satellite images have a virtue of objectivity and enable to statistically evaluate the relationships between different geologic and geomorphologic phenomena.
PL
W miocenie, na obszarze obecnie wschodniej części polskiego zapadliska przedkarpackiego, istniał basen sedymentacyjny utworzony wskutek obciążenia nasuwających się Karpat. Zanim to nastąpiło, obszar przedgórza był intensywnie erodowany. Paleogeńska morfologia była bardzo urozmaicona i miała istotny wpływ na sedymentację późniejszych sekwencji mioceńskich. Dotychczas nie powstała jakościowa mapa paleomorfologiczna okresu przedmioceńskiego na omawianym terenie. Obecnie taka rekonstrukcja wydaje się możliwa. Wykorzystując procedurę palinspastyczną obecny strop podłoża miocenu podniesiono o przybliżoną wartość pogrążenia spowodowanego nasuwającymi się Karpatami. Otrzymana w ten sposób powierzchnia obrazuje późnopaleogeńską morfologię. Maksymalne zróżnicowanie wysokości przekracza 2000 m, a głębokość dolin osiąga 1000 m. Takie zróżnicowanie morfologii podłoża miało niewątpliwy wpływ na architekturę osadów powoli wypełniających przestrzeń akomodacyjną ograniczoną przez ramy basenu mioceńskiego: od północy - przez wał metakarpacki i od południa - przez Karpaty.
PL
Przy wykorzystaniu programu komputerowego PetroMod, wykonano wzdłuż kilkunastu profili geologicznych, przecinających basen polski modelowanie procesów generacji węglowodorów w utworach cechsztynu. Parametry kalibrujące (współczesny rozkład temperatur na określonych głębokościach oraz wyniki oznaczeń refleksyjności witrynitu w różnych formacjach geologicznych) umożliwiły skonstruowanie rozkładu wartości strumienia cieplnego w czasie od permu do dziś na obszarze basenu polskiego. Symulacje komputerowe z wykorzystaniem powyższego modelu rozkładu wartości strumienia cieplnego pozwoliły prześledzić kolejne fazy generacji węglowodorów w utworach cechsztyńskich w poszczególnych częściach basenu polskiego.
EN
PetroMod software enabled the computer modelling of hydrocarbon generation in the Zechstein deposits along several geological cross-section in the Polish Basin. Calibrating parameters (a contemporary field of temperature pattern at the selected deppth and vitrinite reflectance values for various geological formations) enabled to construct an image of heat flow distribution from the Permian to the Recent time in the studied area. Computer simulation applying such a heat flow model determined the individual phases of hydrocarbon generation in the Zechstein deposits of the Polish Basin.
PL
Historia termiczna obszaru Pomorza Zachodniego może być obecnie analizowana za pomocą techniki komputerowej, która umożliwia śledzenie zmian strumienia cieplnego zarówno w czasie, jak i przestrzeni. Na obszarze Pomorza Zachodniego rozkład strumienia cieplnego w czasie dewonu i karbonu charakteryzował się wysokimi wartościami (70-90 mWm [do -2)] a w permie zaczął się gwałtownie zmniejszać, aby osiągnąć w mezozoiku wartości rzędu 60-40mWm[do -2]. Znajomość powyższych wartości strumienia cieplnego umożliwia modelowanie procesów generacji i ekspulsji w osadach dewońskokarbońskich oraz w utworach czerwonego spągowca i cechsztynu. Dla utworów dewońsko-karbońskich na całym obszarze Pomorza Zachodniego (z wyjątkiem rejonu Dobrzycy i Sarbinowa) można spodziewać się stopnia dojrzałości materii organicznej odpowiadającego "oknu gazowemu". Brak uszczelnienia regionalnego pomiędzy utworami karbonu i czerwonego spągowca powoduje, że w osadach klastycznych pennu dolnego należy się spodziewać jedynie wystąpień gazu ziemnego. Na Pomorzu Zachodnim rysuje się tylko jeden obszar- między Daszewem a Reskiem, który wykazuje istnienie dwóch podwyższonych anomalii nasycenia gazem. Uzyskany w wyniku symulacji komputerowych obraz stref dojrzałości materii organicznej w utworach cechsztynu pokazuje, że strefa "okna ropnego" na Pomorzu Zachodnim ograniczona jest do stosunkowo wąskiego pasma o szerokości od 5 do 30 km. Wszystkie dotychczas odkryte w omawianym rejonie złoża ropy naftowej w utworach dolomitu głównego znajdują się w obszarze wymodelowanego "okna ropnego". Ta przesłanka zawęża obszar poszukiwań w cechsztynie do stosunkowo wąskiego terenu, ale jednocześnie pozwala skoncentrować prace geologicznogeofizyczne na lepiej doprecyzowanym poligonie badawczym.
EN
Thermal history in the area of Western Pomerania may be currently analysed by computer-aided simulation in which the spatial and temporal heat flow changes are predicted. In the mentioned area, during the Devonian and Carboniferous time span the values of heat flow was high (70-90 mWm[to -2]) but from the Permian it decreased, and in the Mesozoic period it achieved only 60-40 mWm[to -2] values. The knowledge of the above regularities is the base for modelling of hydrocarbon generation and expulsion in the Devonian and Carboniferous deposits, as well as in the Rotliegend and Zechstein rocks. In the area of Western Pomerania for the Devonian and Carboniferous rocks (beyond the Dobrzyca and Sarbinowo region) the "gas window" could be expected. Because of lack regional seal between the Rotliegend and Carboniferous only gas fields in the Rotliegend deposits may be preserved. The area between Daszewo and Resko seems to be the most perspective. Results obtained by computeraided modelling for the Zechstein deposits show that "oil window' zone is only restricted to narrow (5-30 km) strip of land. Here, all hitherto known oil fields in the Zechstein Main Dolomite are located in the modelled "oil window". These circumstances narrow the exploration in the Zechstein rocks down to relatively slim zone, but on the other hand it allows to concentrate exploration works in the more precise perspective area.
16
Content available Origin and evolution of the polish rotliegend basin
EN
The Polish Rotliegend Basin is a part of the great Southern Permian Basin in Western and Central Europe. Its basin history started in the latest Carboniferous but its origin was rooted as early as Cambrian time. Pre-Permian history of the area of Poland explains the origin of main later frames of the Polish Rotliegend Basin (PRB). It is clearly visible that boundaries of the PRB were determined by eastern margins of the Rheno-Hercynian Basin. Development of the PRB was controlled mainly by climatic and tectonic factors in an intensive rifting regime but it was manifested within individual sedimentary sequences as thicker conglomerate formations or members or increased thickness in most subsiding zones. Detailed sedimentological studies enabled distinguishing in the Rotliegend succession, independently of lithostratigraphic units also allostratigraphic (sequences) ones. The evolution of the Polish Rotliegend Basin-fill had continued within the Permo-Mesozoic Basin (Polish Basin) until the Late Cretaceous when, due to inversion of the central part of the basin, the Mid-Polish Anticlinorium was uplifted. The burial history of the Polish Basin reveals that the Late Permian and Early Triassic periods represent the main rifting phase and its later development resulted from thermal relaxation. A Late Jurassic rifting episode manifested itself only in the central part of the Polish Basin. In the Late Cretaceous basin any external tectonic factors initiating subsidence were unnecessary and the mechanism responsible for subsidence was a simple loading subsidence caused by a great sea transgression. Analysing thermal history of the Polish Basin-fill it was surely evidenced that at the beginning of the Rotliegend volcanic period the high geothermal anomalies occurred in the western part of the developing basin. Initially these anomalies were characterized by higher values (100-150 mWrrf ) during the Late Permian-Early Triassic interval. Such high values were related to syn-rift stages of sedimentary basin development. During Late Triassic and Jurassic time some cooling of rift heat field took place, but the turning point in thermal evolution of the Polish Basin was at the Jurassic/Cretaceous boundary when the southwestern part of the Polish Basin was uplifted and intensively eroded. Then a heat inflow into the southern part of the Polish Basin decreased and distinct features of the prevoius epoch were obliterated in the heat flow field image. Results of burial and thermal analysis of the Polish Basin as well as configuration of Moho surface in Poland seem to suggest the asymmetrical style of the basin model. The uppermost position of Moho is additionally accompanied by a very high helium concentration and corresponds to the area of the highest heat flow during the Late Permian, Triassic and Jurassic in the whole Polish Basin. It may be settled that the described palaeothermal-geochemical-tectonic anomaly, located about 60 km northeast of Wroclaw and continued to the northwest, represented the Late Permian-Early Mesozoic rifting process. It is unambiguously indicative of the asymmetric rift character of the Polish Basin, in which volcanism and deposition of Rotliegend series marked the first phase of its development.
PL
Polski basen czerwonego spągowca (PBCS) jest częścią wielkiego basenu sedymentacyjnego zwanego południowym basenem permskim, leżącym w zachodniej i centralnej Europie. Historia rozwoju polskiego basenu czerwonego spągowca rozpoczęła się na przełomie karbonu i permu. Jednak w jego rozwoju można odnaleźć pewne elementy zakorzenione w już przedpermskim paleozoiku. Rozwój sedymentacji w polskim basenie czerwonego spągowca był kontrolowany głównie przez tektonikę i klimat. Wyraźna zmiana klimatyczna, z warunków wilgotnych na suche, nastąpiła dopiero w górnym czerwonym spągowcu (i to nie w jego najniższej części). Ruchy tektoniczne zaznaczały się natomiast poprzez tworzenie miąższych kompleksów zlepieńców. Takie spojrzenie na opracowywaną sukcesję osadów czerwonego spągowca umożliwiło wyróżnienie kilku sekwencji. Ewolucja polskiego basenu czerwonego spągowca nie skończyła się wraz z transgresją cechsztyńską. Wypełnienie PBCS podlegało dalszej ewolucji związanej z rozwojem polskiego basenu permsko-mezozoicznego. Aby móc śledzić ewolucję wypełnienia PBCS wykonano dla tego obszaru analizę historii pogrążania i analizę historii termicznej. Historia subsydencji basenu polskiego na omawianym obszarze pokazuje, że okres późnego permu i triasu były główna fazę ryftowania, a późniejszy rozwój basenu wynika głównie z relaksacji termicznej. Analizując historię termiczną basenu polskiego widać, że w czerwonym spągowcu występowały tam wielkie anomalie geotermiczne. Anomalie te charakteryzowały się wysoką wartością strumienia cieplnego (100-150 mWm-2) w czasie późnego permu i triasu. Tak wysokie wartości odpowiadają przeważnie synryftowemu etapowi rozwoju basenu. W czasie późnego triasu i jury wystąpiło pewne schłodzenie pola cieplnego, ale punktem zwrotnym w historii termicznej basenu polskiego było pogranicze jury i kredy, kiedy południowo-zachodnia część omawianego basenu została znacznie wyniesiona i zerodowana. Wtedy to wartość powierzchniowego strumienia cieplnego w południowo-zachodniej Polsce istotnie zmalała, a wyraźne cechy termiczne poprzedniej epoki zostały zatarte. Występowanie złóż gazu w osadach czerwonego spągowca ograniczone jest do najwyższej części sekwencji osadowej. Skład gazu ziemnego wykazuje niekiedy znaczne zaazotowanie oraz istotne wzbogacenie w hel. Najwyższe koncentracje helu w gazie ziemnym, tak pod względem objętościowym jak i ilościowym, są zlokalizowane w tym samym miejscu, co permsko-jurajska wysoka anomalia geotermiczna i jednocześnie tutaj najpłycej występuje powierzchnia Moho w Polsce. Wyniki analizy historii pogrążenia i historii termicznej analizowanej części basenu polskiego, jak również konfiguracja powierzchni Moho i związane z nią anomalie paleogeotermiczne oraz wysokie koncentracje helu wskazują na asymetryczny model budowy basenu. Strefa wysokich anomalii paleogeotermicznych, rozciągająca się od obszaru między Wrocławiem i Poznaniem i dalej na zachód, była zapewne głównym obszarem ryftowania. Pierwszym etapem rozwoju polskiego basenu ryftowego był wulkanizm, a następnie sedymentacja w czasie czerwonego spągowca.
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