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EN
There are numerous conventional fields of natural gas in the Carpathian Foredeep, and there is also evidence to suggest that unconventional gas accumulations may occur in this region. The different seismic signatures of these geological forms, the small scale of amplitude variation, and the large amount of data make the process of geological interpretation extremely time consuming. Moreover, the dispersed nature of information in a large block of seismic data increasingly requires automatic, self-learning cognitive processes. Recent developments with Machine Learning have added new capabilities to seismic interpretation, especially to multi-attribute seismic analysis. Each case requires a proper selection of attributes. In this paper, the Grey Level Co-occurrence Matrix method is presented and its two texture attributes: Energy and Entropy. Haralick’s two texture parameters were applied to an advanced interpretation of the interval of Miocene deposits in order to discover the subtle geological features hidden between the seismic traces. As a result, a submarine-slope channel system was delineated leading to the discovery of unknown earlier relationships between gas boreholes and the geological environment. The Miocene deposits filling the Carpathian Foredeep, due to their lithological and facies diversity, provide excellent conditions for testing and implementing Machine Learning techniques. The presented texture attributes are the desired input components for self-learning systems for seismic facies classification.
EN
This article presents the results of digital terrain model analysis and field observations related to occurrence of characteristic forms in landslide surface that may indicate the geological setting. Based on these observations, three characteristic structures were selected occurring on many landslides in the Carpathian Mountains and the Carpathian Foredeep. The former are the wrinkle structures visible on the digital terrain model associated with movement along the bedded surface. The other are the streak structures linked to the occurrence of gravels and sands on the clays. The third mogul type structures are related to cylindrical sliding surfaces formed in clay.
PL
W pracy przedstawiono wyniki badań i analiz, jakie zrealizowano w N części zapadliska przedkarpackiego, których przedmiotem były przede wszystkim skały wapienne górnej jury. Badania miały charakter ściśle analityczny i dotyczyły reinterpretacji: opisów rdzeni wiertniczych z rejonu na północ od Tarnowa, dostępnych danych wiertniczych oraz obserwacji złożowych. W sumie przeprowadzono analizę kilkudziesięciu otworów i została ona wykonana pod kątem identyfikacji w badanych otworach paleokrasu, czyli pogrążonych dużych form krasu, takich jak: leje krasowe, studnie krasowe, jaskinie, korytarze itp. Identyfikacji form krasowych dokonano na podstawie kryteriów litologicznych, cech strukturalno-teksturalnych osadów, obserwacji wiertniczo-złożowych i kryteriów geofizycznych. Przeprowadzone analizy pozwoliły według autorów na identyfikację różnych form paleokrasu w 13 otworach. Rozpoznano szereg małych i średnich form o genezie tektoniczno-krasowej, jak np. szczeliny z różnorodnym wypełnieniem ilasto-piaskowcowym w kolorach: żółtym, rdzawym, czerwonym, zielonym, czarnym, ponadto małe kawerny i kanaliki wielkości od kilku do kilkunastu milimetrów oraz druzy i kawerny wielkości od kilku do kilkunastu centymetrów z wypełnieniem lub bez. Z dużych form krasowych zidentyfikowano struktury, które mogą reprezentować: leje krasowe, studnie krasowe, jaskinie, korytarze i jamy. Wobec lakonicznego opisu rdzeni, który całkowicie pomijał istnienie form krasowych, trudno było szczegółowo zaliczyć rozpoznane struktury do konkretnych form krasowych. W kilku przypadkach identyfikację wsparto pomiarami geofizycznymi i obserwacjami wiertniczymi, te ostatnie wykazały obecność pustek krasowych przewierconych przez odwiert. Wyniki przeprowadzonych badań analitycznych potwierdziły występowanie form paleokrasowych zarówno w obrębie udokumentowanych złóż gazu i ropy, jak i poza nimi. Wobec tego została potwierdzona hipoteza, że część objętości porowej złóż występuje w postaci pustek krasowych. Obecność pustek krasowych tłumaczy niedoszacowanie pojemności porowej na wielu złożach oraz niezrozumiałe dotychczas, występujące w obrębie jednego złoża silne zróżnicowanie ciśnień złożowych. Kras w strefie złożowej może tworzyć jeden połączony system krasowy lub dwa albo więcej takich systemów niezależnych od siebie. Wielkość poszczególnych systemów krasowych może być różna. W rejonie Wyżyny Krakowsko-Wieluńskiej występuje wiele jaskiń i systemów krasowych, a objętość poszczególnych jaskiń wynosi od kilkudziesięciu metrów sześciennych do nawet 12 tys. m3 , a pojedynczych komór do 4,5 tys. m3 . Identyfikacja paleokrasu na złożach jurajskich będzie miała duże znaczenie dla właściwej oceny zasobów złóż, zarówno istniejących, jak i nowych, gdyż bez uwzględnienia pojemności form krasowych obliczone zasoby będą niepełne. Obecność struktur paleokrasu na złożu będzie też miała istotne znaczenie w procesie poszukiwań, wiercenia i eksploatacji złóż ropy i gazu. Przedstawiony problem jest zatem bardzo ważny i wymaga dalszych prac, badań i analiz.
EN
This article presents the results of research carried on Cenomanian sandstones and mainly the Upper Jurassic limestone rocks located in the north part of the Carpathian Foreland. The research was strictly analytical and focused on the reinterpretation of the drilling core descriptions and drilling data observations collected from the Tarnów area. In general, the analysis was carried out on several dozen wells and it was performed in order to identify paleokarst phenomena or deep karst formations, such as: karst, karstic wells, caves, corridors, etc. The identification of karst formations was based on lithological criteria, structural-textural sediments features, drilling observations, and geophysical criteria. The author identified the paleokarst phenomena on 13 wells. A number of small and medium-sized forms with tectonickarst genesis were identified, such as natural channels with various clay-sandstone fillings in the following colors: yellow, rusty, red, green, and black. Channels with a few to several millimeters apart and cavities from a few to several centimeters with or without filling were observed. Large karst formations, such as karstic wells, caves, corridors and cavities were also identified. Due to the laconic description of the cores, which completely disregarded the existence of karst forms, it was difficult to recognize karst form structures in detail; however, in several cases, identification supported by geophysical measurements and drilling observations showed the presence of karst voids in the drilled well. The results of the analytical tests confirmed the presence of paleokarst forms within the documented gas and oil fields and outside of them. Based on the analysis, the hypothesis that part of the pore volume of the oil and gas reserves is located in the karst forms was confirmed. The presence of karst voids explains the underestimation of the pore volume of many oil and gas fields and the strong variations of the well pressure during production. The karst in the deposit zone may form one combined karst system or more karst systems independent of each other. The size of individual karst systems can vary. In the area of the Krakow–Wielun Upland there are many caves and karst systems, and the volume of caves ranges from several to even 12.000 m3 , with the volume of the individual chambers attaining 4.5 thousand m3 . The significance of the karst forms identification for proper assessment of reserves and production resources is very important and requires further research.
PL
W skałach miocenu zapadliska przedkarpackiego zauważono zjawisko zawyżania pomiarów promieniotwórczości naturalnej rejestrowanych w otworze wiertniczym dla mułowców. To zjawisko powoduje problemy w rozróżnianiu na podstawie profilowania naturalnej promieniotwórczości tych skał od iłowców, które charakteryzują się gorszymi parametrami petrofizycznymi. W niniejszej pracy badano kolejne możliwe źródło podwyższonej radioaktywności skał mułowcowych, to jest zawartość minerałów ciężkich, które wykazują tendencję do gromadzenia pierwiastków promieniotwórczych – uranu i toru. Minerały ciężkie, należące do grupy minerałów akcesorycznych, takie jak cyrkon, apatyt, monacyt, rutyl, granat i tytanit, charakteryzują się podwyższoną promieniotwórczością ze względu na podstawienia w sieci krystalicznej U i Th. Na testowych próbkach wykonano pomiar naturalnej promieniotwórczości metodą spektrometrii gamma, przy wykorzystaniu aparatu RT-50 firmy Georadis. Następnie z próbek skał wydzielono minerały ciężkie, przy użyciu cieczy ciężkiej, uprzednio rozdzielając próbki na frakcje ziarnowe, w celu ułatwienia separacji frakcji ciężkiej. Poszczególne frakcje ziarnowe pozbawione minerałów ciężkich złączono z powrotem i wykonano ponowny pomiar zawartości uranu, toru i potasu. Wykonano także obserwacje mikroskopowe w celu jakościowej analizy składu mineralogicznego wydzielonej frakcji ciężkiej. W badanych próbkach zidentyfikowano między innymi ziarna cyrkonu, turmalinu, granatu, rutylu, apatytu, chlorytu czy tytanitu. Przeprowadzone wyniki pomiarów naturalnej promieniotwórczości, przed i po wydzieleniu minerałów ciężkich, nie dają jednoznacznej odpowiedzi na postawiony problem zawyżonych wskazań sondy gamma. Konieczne jest zwiększenie ilości analizowanych próbek. Zaobserwowano trend spadku ilości U i Th w próbkach, z których wydzielono frakcję ciężką. Jednak zmiany promieniotwórczości są na tyle niewielkie, że nie pozwalają na wyciągnięcie ostatecznych wniosków. Dodatkowe analizy są potrzebne, aby ocenić wpływ pozostałych źródeł uranu i toru w badanych skałach, takie jak zawartość materii organicznej czy udział toru we frakcji ilastej.
EN
In the Miocene rocks of the Carpathian Foredeep, the occurrence of overestimating the measurements of natural radioactivity logs for mudstones was noticed. This phenomenon causes problems with recognition on the basis of natural radioactivity profiling of these rocks from claystones, characterized by inferior petrophysical parameters. In this study, another possible source of increased radioactivity of mudstone rocks, i.e. the content of heavy minerals that tend to accumulate radioactive elements - uranium and thorium - was investigated. Heavy minerals, belonging to the accessory minerals, such as zircon, apatite, monazite, rutile, garnet and titanite, are characterized by increased radioactivity due to substitutions of U and Th in the crystal lattice. Natural radioactivity of the test samples was measured using the gamma spectrometry method with the RT-50 device from the Georadis company. The heavy minerals were then removed from the rock samples using a heavy liquid, previously separating the samples into grain fractions to facilitate the separation of the heavy fraction. The individual grain fractions deprived of heavy minerals were put back together and the uranium, thorium (and potassium) content was remeasured. Microscopic observations were also made to qualitatively analyze the mineralogical structure of the separated heavy fraction. In the tested samples, among others: zircon, tourmaline, garnet, rutile, apatite, chlorite or titanite grains were identified. The results of the measurements of natural radioactivity, before and after the separation of heavy minerals, do not give a clear answer to the problem of excessive indications of the gamma logs. It is necessary to increase the number of analyzed samples. The trend of decreasing amounts of U and Th in the samples from which the heavy fraction was isolated was observed. However, changes in radioactivity are so small that they do not allow to draw final conclusions. Additional analyzes are needed to assess the impact of other sources of uranium and thorium in analyzed rocks, such as the content of organic matter or Th content in clays.
EN
This paper was made using geological and well logging data from the Cuban oilfield area and the Polish Carpathian Foredeep gas deposit to compare the interpretation process and underline similarities and differences between data analysis from two reservoir rocks of different lithology. Data from conventional hydrocarbon deposits, i.e. the Mesozoic Cuban carbonate formation and Miocene shaly-sandy sediments were processed and interpreted using Techlog (Schlumberger Co.) software. Selected approaches were used to determine the step by step volume of shale, total and effective porosity, water/hydrocarbon saturation (Quanti) and for the comprehensive interpretation of well logs (Quanti Elan). Brief characteristics of the carbonate and siliciclastic formations were presented to indicate that the interpretation methodology oriented to the determination of petrophysical properties depends strongly on the type of reservoir. Cross-plots were presented for primary mineral composition recognition, determination of m exponent and resistivity of formation water in the Archie equation. Effective intervals for the carbonate reservoir were calculated according to the Cumulative Hydrocarbon Column methodology. Finally, the results of the interpretation of well logs were presented as continuous curves of mineral composition, including shaliness, porosity and hydrocarbon saturation. The conclusions included recommendations for the effective comprehensive interpretation of well logs in the carbonate and siliciclastic reservoirs.
EN
Twin structural traps that lie within the Miocene strata of the Carpathian Foredeep that are localized above Cierpisz and Mrowla-Bratkowice highs exhibit identical bright-spot seismic anomalies, but only those associated with the Cierpisz high are profitable gas reservoirs. Bright spots can be a result of weak gas or water saturation, but also seismic interference known as tuning effect. For these reasons, it is crucial to differentiate between seismic anomalies. In this article, we present the possibilities of verification of seismic anomalies that occur within the siliciclastic Miocene sediments of the Carpathian Foredeep with the application of AVO analysis and spectral decomposition. AVO methodology enabled to limit the number of anomalies that are present in the post-stack seismic data. These anomalies, however, may also be a result of tuning which is common for the heterolithic sequences in the Miocene sediments of the Carpathian Foredeep. For classification of anomalies in the view of the above, spectral decomposition based on the Basis Pursuit algorithm was applied. Spectral decomposition enabled to divide AVO anomalies in those that are the result of gas saturation and the tuning effect. Gas-saturated zones are characterized by higher spectral amplitudes of the lower frequency range, whereas tuning effect yields higher spectral amplitudes for the higher frequency content. This relation is visible for the data set and enables qualitative differentiation for the set of seismic anomalies.
PL
Exploited conventional reservoirs located in the south-eastern part of Poland, characterized by favorable petrophysical parameters, are being used for underground gas storage under appropriate technological and economic conditions, as exemplified by UGS Husow, Strachocina, Swarzow or Brzeznica. The use of subsurface modeling software for visualizing spatial reservoir parameters’ distribution within old gas fields, is associated with a significant degree of uncertainty resulting from a wide variation in time of data acquisition and factors affecting its representativeness. The article presents the concept of using modeling adapted for old, conventional gas reservoirs, assuming the selection and processing of reinterpreted gamma ray logs to create pseudo-facies classification. Visualization of its elements, along with geological and reservoir interpretation, can be used for further analysis, including decision making in the aspect of picking out predisposed zones for new wells associated with increasing UGS total storage capacity. Modeling was conducted with the use of the Baker Hughes JewelSuite™ Subsurface Modeling software.Słowa kluczowe: modelowanie 3D, Karpaty, zapadlisko przedkarpackie, podziemne magazynowanie gazu.
EN
Exploited conventional reservoirs located in the south-eastern part of Poland, characterized by favorable petrophysical parameters, are used for underground gas storage under appropriate technological and economic conditions, which can be exemplified by UGS Husow, UGS Strachocina, UGS Swarzow or UGS Brzeznica. The use of subsurface modeling software for visualizing spatial reservoir parameters’ distribution within old gas fields is burdened with significant uncertainty related to wide range of time diversity of data acquisition and factors affecting its representativeness. The article presents the concept of using modeling adapted for old, conventional gas reservoirs, assuming the selection and processing of reinterpreted gamma ray logs to create pseudo-facies classification. Visualization of its elements, along with geological and reservoir interpretation, can be used for further analysis, including decision making in the aspect of typing perspective zones for new wells associated with increasing UGS total storage capacity. Modeling was conducted with an use of Baker Hughes JewelSuite™ Subsurface Modeling software.
EN
Salt deposits in the Wieliczka area (Wieliczka Salt Deposit – WSD) in southern Poland comprise salt-rich strata belonging to an evaporite succession that originated in the Carpathian Foredeep basin in the Middle Miocene Badenian (Serravallian) times, ca 13.81–13.45 Ma. Although they have been mined since the 13th century and decades of investigations provided abundant data on their origin and structure, some aspects of their geological evolution are still not fully understood. This study presents current concepts on the lithostratigraphy and tectonics of the WSD. The salt-bearing facies developed near to the southern basin margin, delineated by the Carpathian orogenic front. Such a location triggered the redeposition of sediments and gravity-driven deformation followed by tectonic deformation related to the forelandward advancement of the Carpathian thrusts. As a result, the WSD consists of folds and slices composed of two main salt members: (1) the stratified salt member, with intercalating salt, sulphates and siliciclastics, and (2) the boulder salt member, built of clays with large, isolated blocks of salt. The stratified member contains abundant meso-scale tectonic structures recording the soft-sediment deformation and deformation related to the northward tectonic push exerted by the advancing Carpathian thrust wedge. The boulder member originated due to the syntectonic erosion of evaporites along the basin margins and their redeposition during progressive northward migration of the Carpathian front. Recent interpretations of seismic data imply that the WSD constitutes the core of a triangle zone developed at the contact of the Carpathian orogenic wedge with the backthrust-displaced foredeep sedimentary fill. Meso-scale examples of sedimentary and tectonic structures in the salt-bearing succession exposed in the underground Wieliczka Salt Mine are described and their formation modes discussed.
EN
The early Badenian interval in the Central Paratethys realm is characterized by a major marine transgression into the Pannonian and Carpathian Foredeep basins. In the western part of the Polish Carpathian Foredeep, Badenian sedimentation started generally with conglomerates (Dębowiec Formation) passing into a thick succession of claystones and mudstones with rare sandstone interbeds (Skawina Formation). Profiles containing a full sequence of lower Badenian strata are relatively rare, and are mainly known from boreholes. In this paper, we present new results on samples taken from such a borehole (Kaczyce K2/07) located near the town of Cieszyn. We focus on reconstructing the chronology of the lower Badenian marine sediments at the beginning of the transgression in the Carpathian Foredeep (lower Skawina Fm.) using radio-isotopic dating (40Ar/39Ar) of a volcanoclastic layer (tuff and tuffite) and biostratigraphy of calcareous nannoplankton and foraminifera.The weighted mean 40Ar/39Ar age for sanidine separates from the tuff provided an age of 14.27 ± 0.03 Ma. This age is consistent with the NN5 and MNN5a nannofossil zones determined in this study. Our foraminiferal assemblages show that the basal beds of the Skawina Formation up to the tuffites correspond to the Orbulina suturalis–Praeorbulina glomerosa Zone (according to Cicha et al., 1975) and cover the interval of the Lower Lagenidae Zone–lowermost Upper Lagenidae Zone (Grill, 1941). The petrographic data from the tuffite allow correlation of the tuffite from the Kaczyce K2/07 borehole to the level of the Chełmek Tuffite Bed (Alexandrowicz, 1997) providing a regional correlation horizon for future studies.
EN
The article presents the results of the reinterpretation of the results of the two-cycle DST of the Mesozoic strata in the W-3 well to assess the changes in permeability of reservoir rocks in the test zone. Two-dimensional diagrams of the first and second pressure restoration curves in the semi-logarithm coordinate system were taken into account. The determined linear regression equations of these sections give simultaneously the extrapolated value of the reservoir pressure and the directional coefficient. The “logarithmic approximation” method used in hydrogeology was used to determine the radius of the perimeter zone with altered permeability of the water-bearing rocks of the Mesozoic.
PL
W południowej strefie zapadliska przedkarpackiego mającej bezpośredni kontakt z nasunięciem karpacko-stebnickim powstał szereg złóż gazu ziemnego o odmiennej genezie. Zasadniczy wpływ na utworzenie się tych pułapek miały różne procesy, najważniejsze z nich to: morfologia podłoża podmioceńskiego, środowisko i warunki sedymentacji oraz nasunięcie się płaszczowin karpackich na utwory miocenu autochtonicznego. Współoddziaływanie tych czynników doprowadziło w efekcie końcowym do powstania złóż gazu ziemnego w pułapkach o charakterze: litologicznym, tektonicznym, facjalnym i stratygraficznym. W warunkach kompresji tektonicznej wytworzyły się też w strefach szczytowych złoża gazu z wodą podścielającą, poniżej których stwierdzono ponownie strefy gazowe – co wydaje się być pozornie nielogiczne. W artykule zaprezentowano koncepcję przedstawiającą prawdopodobny proces i mechanizm tworzenia się takich pułapek oraz pułapek na izolowanych lub częściowo izolowanych grzbietach podłoża prekambryjskiego w warunkach sedymentacji na podmorskim stożku napływowym. Znajomość genezy tego typu pułapek jest bardzo istotna dla właściwej oceny zasobów oraz rozwiercania i eksploatacji złóż.
EN
A number of gas fields which are connected with various sedimentary conditions, have accumulated in the southern part of the Carpathian Foredeep contacting directly with the Carpathian-Stebnik overthrust. Various processes have an influence on the evolvement of reservoir traps but the most important ones are: the morphology of the under-Miocene substrate, sedimentary environment and the overlap of the Carpathian nappes on the autochthonous Miocene strata. The interaction of these factors have resulted in gas reservoirs formation in lithological, tectonic and stratigraphic traps. Under conditions of tectonic compression, gas reservoirs with underlying water have developed, where other gaseous areas in the same trap have been found. The article shows the conception describing probable mechanisms having an influence on the process of reservoir traps development in the area of isolated or partially isolated Precambrian ridges connected with submarine fan’s environment. Determining the origins of these types of traps is crucial for proper reservoir resources assessment and subsequent exploitation.
PL
W artykule przedstawiono studium dotyczące możliwości wykorzystania energii geotermalnej w obszarze znajdującym się na obszarze zapadliska przedkarpackiego w rejonie Tarnowa. Podano informację na temat budowy geologicznej analizowanej strefy oraz dokonano charakterystyki triasowego zbiornika wód termalnych, najbardziej interesującego w tym rejonie. Analiza została wykonana na podstawie parametrów hydrogeotermalnych (temperatura, mineralizacja, porowatość, przepuszczalność, wydajność), które uzyskano z otworów geologicznych i naftowych zlokalizowanych w strefie miasta oraz na terenach przyległych. W wyniku analizy oszacowano potencjalne zasoby energetyczne. Wykazano, że najlepsze perspektywy dla rozwoju geotermii w analizowanym obszarze stwarza wykorzystanie tego zbiornika głównie w aspekcie balneorekreacji.
EN
This work is a study on the possibility of using geothermal energy in the area of the Carpathian Foredeep in the Northern area of Tarnów. The information presents the geological structure of the analyzed area along with the characteristics of the Triassic thermal water reservoir, the most interesting in the region. The analysis was conducted on the basis of hydrogeothermal parameters (temperature, mineralization, porosity, permeability, efficiency), which were obtained from the geological and petroleum wells located in the zone of the city and adjacent areas. The analysis estimated potential energy resources. It was pointed out that the best prospects for the development of geothermal energy in the analyzed reservoir makes use in terms of balneo-recreation.
PL
Główne obszary wydobycia gazu ziemnego w Polsce występują w czterech regionach: na Niżu Polskim, w zapadlisku przedkarpackim, w Karpatach i w strefie bałtyckiej. Około 75% zasobów gazu znajduje się w utworach miocenu i czerwonego spągowca, a pozostałe w osadach kambru, dewonu, karbonu, cechsztynu, jury i kredy. Zapadlisko przedkarpackie, będące rowem przedgórskim powstałym u czoła nasuwających się ku północy Karpat, jest najmłodszą jednostką alpejską na obszarze Polski. Biorąc pod uwagę cechy strukturalne, sedymentologiczne i stratygraficzne, zapadlisko można podzielić na część wewnętrzną i zewnętrzną oraz zachodnią i wschodnią. Jest ono wypełnione osadami molasowymi miocenu. Tworzy je zespół nawzajem przeławicających się piaskowców, mułowców i iłowców. Osady mioceńskie mają na terenie Polski miąższość do 3500 m i cechują się dużym zróżnicowaniem litologicznym. Sekwencje profilu, gdzie dominują piaskowce i zapiaszczone mułowce, tworzą oddzielne horyzonty gazonośne. Ich liczba w poszczególnych profilach odkrytych złóż gazowych waha się od kilku do 24 na polu gazowym Przemyśl. W 2014 roku stan wydobywlanych zasobów gazu ziemnego w Polsce wynosił 129,75 mld m3 (zasoby bilansowe i pozabilansowe) i w porównaniu z rokiem poprzednim był mniejszy o 4,55 mld m3. Ubytek zasobów powstał głównie w wyniku wydobycia. Biorąc pod uwagę poszczególne regiony geologiczne Polski zasobne w gaz ziemny, przeprowadzono analizę wielkości zasobów wydobywalnych, przemysłowych i ich wydobycia na przestrzeni lat 2007–2014 w wybranych złożach przedgórza Karpat.
EN
The main areas of natural gas production at present in Poland, are in four regions, the Polish Lowlands, in the Carpathian Foredeep, the Carpathians and in the Baltic area. Natural gas deposits have also been documented in the foothills of the Carpathians; small gas resources can also be found in small deposits in the Carpathians and in the Polish economic zone of the Baltic Sea. Approximately 75% of the gas resources are located in the Miocene and Rotliegend, and the remaining are in the sediments of the Cambrian, Devonian, Carboniferous, Zechstein, Jurassic and Cretaceous. The Carpathian Foredeep, which is a foreland trench created at the head of an area which gives rise to the north Carapathians, is the youngest alpine unit on Polish territory. Taking into account the structural features, sedimentological and stratigraphic depression can be divided into inner and outer parts and western and eastern. It is filled with Malasse Miocene sediments. They consist of a team of mutually penetrating sandstones, siltstones and claystones. Miocene sediments in Poland have a thickness of up to 3500 m and is characterized by great lithological diversity. Sequences profile dominated by sandstones and gritty mudstones form separate gas-bearing horizons. Their number in the individual profiles of discovered gas deposits, varies from a few to 24 in the Przemysl gas field. In 2014, the state of recoverable natural gas reserves amounted to 129.75 billion m3 (balance sheet and off-balance sheet resources) and compared with the previous year’s resources decreased by 4.55 billion m3. Depletion arose mainly as a result of exploration. Taking into account the various Polish geological regions that are rich in natural gas, an analysis of the size of recoverable resources, industrial and their exploration in the period 2007 and 2014 from selected deposits of the Carpathian foothills was carried out.
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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The late Early–Middle Miocene Stebnyk Formation is a ~600–2000 m thick unit of the Boryslav-Pokuttya and Sambir nappes, which contains a molasse succession of the Carpathian Foredeep incorporated within the marginal part of the Outer Eastern Carpathian accretionary wedge. In the valley of thePrutRiver, between Deliatyn and Lanchyn, the Stebnyk Formation covers the alluvial fan deposits of the Sloboda Conglomerate and the deltaic deposits of the Dobrotiv Formation in the south, and the lagoonal salty clays of the Vorotyscha Formation in the north. The Stebnyk Formation is built of mainly rose, greenish and grey calcareous mudstones intercalated with several variable sandstone beds, including thick-bedded packages. The occurrence of tetrapod footprints and raindrop imprints, as well as the overall red-be character prove prevailing continental conditions during deposition of the formation, which is interpreted as sediments of a delta plain with distributary channels filled by the thick sandstone beds and associated by intercalations of thinner beds referred to channel levees and crevasse splays. The upper part of the Stebnyk Formation contains marine microfossils of the NN4 Zone, and locally to the NN5 Zone, corresponding to the early Badenian transgression in the region. In the regional scale, the Stebnyk Formation shows a polarity of facies, with a high contribution of conglomerates and thick-bedded sandstones in the lower part in the north west and fining to the south east, with transportation from the west and north west. The sediments accumulated in an elongated subsiding zone between the rising Carpathian orogen and the forebulge elevation of the foreland, in a warm and semi-dry climatic conditions corresponding roughly to the Mid-Miocene Climatic Optimum. The accumulation was balanced by a subsidence caused by sinking of the platform slab and by sedimentary loading.
EN
Brown coal and overlying sand strata from the Łukowa-4 borehole, located in the northeastern sector of the Carpathian Foredeep in Poland, were studied for palynology. These strata are underlain by Upper Eocene sands, and covered by Middle Miocene rocks. Coal beds yielded infrequent sporomorphs and freshwater algae Botryococcus. The presence of the latter indicates that these deposits accumulated in a freshwater environment whereas sporomorph assemblages point to the presence of mixed forests with a significant portion of thermophilous taxa. Age of the coal beds has been established based both on the presence of species that appear for the last time in the Early Oligocene, and on the similarity with sporomorph spectra from the Lower Oligocene of the Polish Lowlands. Overlying sands yielded marine dinoflagellate cysts, which point to a marine sedimentary setting, and frequent sporomorphs. The latter indicate the presence of mixed mesophytic forests, bush swamps, swamp forests, and riparian forests in the vicinity of lacustrine environments. Stratigraphic analysis of dinoflagellate cyst and sporomorph assemblages suggests that the sands accumulated in early stages of Miocene transgression in the Carpathian Foredeep in the latest Early–early Middle Miocene. Our climatic interpretation of the sporomorph spectra suggests that the climate during deposition of the strata was relatively warm, although less frequent thermophilous taxa recorded in the Miocene sands suggest a slightly cooler climate than that deducted from the spectra yielded by the underlying Lower Oligocene coal beds. Correlation of Lower Oligocene coal beds with neighbouring coeval marine sands suggests diverse morphological conditions in the Carpathian foreland at that time, partly covered by a sea, and partly emerged. A similar, morphologically diverse basement in the Carpathian foreland favoured accumulation of Lower Miocene phytogenic deposits. A similar stratigraphic position of both Lower Oligocene and Lower Miocene coal beds in the Carpathian Foredeep may result in a false correlation of these strata devoid of fossils, which are commonly regarded as Miocene.
EN
The Badenian section of Anadoly near Kamyanets Podilskyy (Ukrainian Carpathian Foredeep Basin) consists of the Tyras Fm. (gypsum and Ratyn Limestone) and the Ternopil Mb. of the Kosiv Fm. The latter are 5.3 m thick and are composed of dark grey mudstones with limestone intercalations. This study indicates the occurrence of over 54 species of benthic foraminifers and 10 species of planktonics. Benthic foraminifera are represented mainly by calcareous forms; agglutinated tests are very rare. Planktonic foraminifera appear in the upper part of the succession studied. Five benthic foraminiferal assemblages are recognized: A (Elphidium/Lobatula/Astrononion) B (Hauerinidae), C (Cibicidoides/Lobatula), D (Porosononion) and E (Uvigerina/Bulimina). The foraminiferal record indicates deposition in a shallow subtidal environment (20 m depth) of normal marine salinity and temperate waters followed by gradual deepening of the basin to >50 m. Analysis of foraminiferal assemblages indicates that bottom waters were highly oxygenated during deposition of the lower and middle parts of the Anadoly sequence. During deposition of the upper part of the sequence the oxygenation of bottom water gradually decreased, as expressed by a large decrease in the proportion of oxic species and an increase in dysoxic ones. The same set of samples yielded low amounts of palynological organic matter represented by dominant black opaque phytoclasts; bisaccate pollen grains and dinoflagellate cysts are rare. Taxonomically impoverished assemblages of the latter consist of dominant Polysphaeridium and Cleistosphaeridium placacanthum associated with Lingulodinium machaerophorum and a few other taxa. The taxonomically richest assemblage was found in the topmost sample. These changes were interpreted as indicative for increased salinity in the surface water layer, with its maximum in the middle part of the section; the assemblage from the topmost part is characteristic for normal marine salinity.
PL
Nagromadzenia soli potasowo-magnezowych w złożu Stebnik na Ukrainie występują w postaci odrębnych soczewek lub warstw o zaburzonym kształcie i często nieregularnym rozmieszczeniu. Miąższość eksploatowanych pokładów soli potasowo-magnezowej zmienia się od 4 m do 150 m. Kopalinę stanowi głównie minerały sylwinu, w złożach eksploatowano również karnalit, kainit i langbajnit. Występujące ponadto minerały to polihalit, epsomit, kizeryt. Do badań wykorzystano próbki pobrane na III poziomie kopalni Stebnik (Rudnik 1). Są to sole o barwie różowej zawierające polihalit, sylwin z dodatkiem anhydrytu i halitu. W czasie obserwacji mikroskopowych (w świetle przechodzącym i metodą spektroskopii Ramana), skupiono się przede wszystkim na kryształach halitu i powstałych w nich inkluzjach. Inkluzje w badanym materiale występują bardzo rzadko pojedynczo, zazwyczaj tworzą grupy, które posiadają specyficzne cechy, dzięki którym wyodrębniono ich trzy główne typy (ze względu na kształt): • Inkluzje wydłużone (podłużne) - tak zwane inkluzje młode, proces tworzenia się unkluzji został uchwycony dopiero co po zamknięciu się szczeliny. • Inkluzje eliptyczne - inkluzje uległy już wstępnym procesom przekształceń i zamykania, mają wyraźniej łagodny kształt i formę zbliżoną do elipsy. • Inkluzje kuliste - tak zwane inkluzje dojrzałe, które pod względem kształtu uzyskały formę idealną -została uzyskana najniższą energie swobodną. Badane inkluzje maja charakter inkluzji wtórych. Najczęściej są wypełnione kilkoma substancjami jednocześnie, przeważnie jest to materia organiczna, CO2 oraz hematyt. Dodatkowo w czasie szczegółowej analizy inkluzji zbadano wrostki chalkopirytu, hematytu oraz rzadszych minerałów minerałów takich jak lazuryt (Na,Ca)8[(S,Cl,SO4,OH)2 |(Al6Si6O24)], goethyt FeO(OH) czy anataz TiO2. Dane uzyskane w czasie badań porównano z archiwalnymi danymi (Kovalevich, 1979) i na tej podstawie ustalono spójny wniosek końcowy dotyczący mineralogii złóż.
EN
The subject of research was salt deposit located in Stebnyk (Ukraine). In the Stebnyk salt mine is a very rich accumulation of potassium-magnesium salts, created in the Miocene basin of Carpathian Foredeep. Potassium-magnesium salts occur in the salt deposit as separate deformed lenses and layers often irregularly distributed. The thickness of the potassium-magnesium salts layer varies from 4 m to 150 m. The potash minerals are represented mainly by sylvite and carnallite, kainite and langbeinite, accompanied by polyhalite, epsomite and kieserite. Detailed mineralogical studies of Stebnyk salts area were carried out in the 70s (V. M. Kovalevich 1979). Currently, these data are correlated with the results obtained and on the basis of these data it has been determined the most reliable results. The inclusions are very rare one, usually form groups, which have specific characteristics by which managed to extract the four main types (due to the shape): inclusions elongated (oblong) - the so-called inclusions young, the process was captured just after the closing of the gap. • elliptical inclusions - inclusions were already pre-processes of transformation and closing, have clearly mild shape and form similar to an ellipse. • spherical inclusions - the so-called inclusions mature, which in terms of the shape of the desired form obtained from the point of force (the lowest free energy). Tested inclusions are secondary. Most are filled with several substances at the same time, usually the organic substance, CO2 and hematite. In addition, during the thorough analysis of the inclusions were examined inclusions of chalcopyrite, hematite and rare minerals such as lazurite (Na, Ca)8[(S, Cl, SO4, OH)2 | (Al- 6Si6O24)] and goethite FeO(OH) anatase TiO2.
EN
It is commonly known that in the Upper Silesia the coal deposits exist. However, in that region also other mineral deposits such as therapeutic water are exploited. Such situation while two different deposits are exploited might lead to some problems. The Goczałkowice-Zdrój spa is the one amongst two spas in the Upper Silesia. There are three boreholes which exploits therapeutic water in Goczałkowice-Zdrój. The brine, which is exploited there, contains high concentration of iodine and ferrous ions. However the mineralization of water has decreased since the boreholes were drilled. The hydrogeological system of mineral water is very vulnerable for any changes. That is the reason why it should be well protected, especially while exploited water is used for therapeutic aims.
PL
Artykuł przedstawia wyniki wykorzystania wysokorozdzielczej mikrotomografii komputerowej w analizie strukturalnej oraz ilościowej przestrzeni porów i szczelin w piaskowcach mioceńskich. Dodatkowo wykonano badanie przepuszczalności analizowanych skał. Próbki zostały pobrane z odwiertu S-3, zlokalizowanego we wschodniej części zapadliska przedkarpackiego. W celu przeprowadzenia badania wykonano dwie serie naświetlania rentgenowskiego próbek. Pierwszy zestaw próbek został wytypowany dla uzyskania przestrzennego rozkładu ziaren, porów oraz szczelin. Długość boku woksela (tzn. najmniejszego elementu objętości) w tym etapie badań wynosiła około 26 μm. Drugi zestaw naświetlania został wykonany dla zobrazowania elementów strukturalnych o wielkościach od około 3 μm do 26 μm oraz cech petrofizycznych. Wynikiem przeprowadzonych badań jest charakterystyka analizowanych skał, która umożliwia podział próbek na dwie grupy. Pierwsza grupa próbek posiada cechy strukturalne oraz petrofizyczne typowe dla skał złóż konwencjonalnych, natomiast druga grupa – dla skał złóż typu niekonwencjonalnego. Właściwe rozpoznanie parametrów petrofizycznych każdego typu złoża stanowi kluczowy element optymalizacji procesu jego udostępniania.
EN
The article presents results of high-resolution computed microtomography use in the structural analysis and quantification of pores and fractures in Miocene sandstones. Furthermore, the permeability studies of rocks were performed. Miocene samples were taken from well S-3, located in the eastern part of the Carpathian Foredeep. For the aforementioned analysis two series of X-ray irradiation were performed. The first set of samples was selected to obtain the spatial distribution of grains, pores and fractures. At this stage of the study, the length of the voxel side amounted to approx. 26 μm. The second set of X-ray exposure was performed to reveal structural elements and petrophysical characteristics of sizes ranging from approx. 3 μm to 26 μm. The result of performed characteristics is the division of samples into two groups. The first group of samples has structural and petrophysical features of rocks typical for conventional reservoir deposits, while the second – for the unconventional type. Appropriate identification of petrophysical parameters of the formation is a key element for the optimization of the reservoir development.
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