Wyniki wyszukiwania - BazTech

1

Efektywność odkrywania zasobów gazu ziemnego metodami wiertniczymi w polskiej części Zapadliska Przedkarpackiego

Jucha S.F., Pajda R.

Wiertnictwo, Nafta, Gaz

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2001

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R. 18/2

351-392

PL

W pracy przedstawiono wyniki metodycznej analizy efektywności odkrywania zasobów gazu ziemnego za pomocą wierceń geologiczno-poszukiwawczych w wyróżnionych poziomach stratygraficznych w polskiej części Zapadliska Przedkarpackiego, w trzech stopniach uogólnienia: najbardziej szczegółowym, stanowiącym zbiór danych dla dalszych analiz (79 pozycji), zbiorczym, liczbowym i graficznym (7 zestawień), dla określonych poziomów stratygraficzno-złożowych, ogólnym, obejmującym elementy końcowej analizy i syntezy efektywności odkrywania zasobów węglowodorów za pomocą wierceń poszukiwawczych w wyróżnionych poziomach stratygraficznych w polskiej części Zapadliska Przedkarpackiego. Badania objęły następujące poziomy stratygraficzno-złożowe Zapadliska Przedkarpackiego: miocen autochtoniczny (N1) - 65 pozycji, cenoman (Cr2) - 3 pozycje, jura (J3 - malm) - 8 pozycji, trias (T) - 1 pozycja, karbon (C2) - 1 pozycja, i dewon (D3) - 1 pozycja. Typ złóż obejmował tylko złoża gazowe. Prace były realizowane w ramach badań statutowych częściowo finansowanych przez Komitet Badań Naukowych w Warszawie. Zasoby gazu ziemnego, udokumentowane w głównym basenie polskiej części Zapadliska Przedkarpackiego wskazują na wybitne związki przyczynowe i genetyczne, o czym wyraźnie informują podane wielkości. Analiza wykazała, że zasoby gazu ziemnego, niezależnie od ich składu, zmieniają się także w układzie stratygraficznym z głębokością na tych samych złożach, poczynając od kredy, jury, triasu, karbonu, aż do dewonu. W opracowaniu pominięto stwierdzone akumulacje złożowe ropy naftowej w utworach kredy (cenoman), jury (malm). Należałoby również podkreślić, że głębokość występowania złóż gazu ziemnego w postaci akumulacji gazowych lub kondensatowych może mieć miejsce głównie do 3500 metrów, biorąc pod uwagę średni stopień geotermiczny. Rysuje się więc wiele ciekawych zagadnień, dotyczących genezy złóż, kierunków ich migracji oraz potencjalnych, nie wykrytych jeszcze wielu zależności wynikających z poznanych dotąd warunków ich akumulacji. Główną zaletą przeprowadzonych badań i studiów zasobowych jest wymierność niektórych wyników analizy głównych poziomów stratygraficznych polskiej części Zapadliska Przedkarpackiego, zilustrowanych w postaci zestawień liczbowych i wykresów. Interpretację wykrytych zależności pozostawia się jako podstawę dalszych prac w aspekcie poszukiwawczym lub badań naukowych.

EN

The paper gives the results of methodical analyses of the efficiency of natural gas resources discovery using geological-exploration drilling in the selected stratigraphic horizons in the Polish part of the Carpathian Foredeep in three degrees of generality. The following stratigraphic-reservoir horizons of the Carpathian Foredeep were analysed: autochthonous Miocene (N1) - 65 items, Cenomanian (Cr2) - 3 items, Jurassic (J3- Malm) - 8 items, Triassic (T) - 1 item, Carboniferous (C2) - 1 item, and Devonian (D3) - 1 item. These were only gaseous deposits. The analysis has shown that regardless their composition, the natural gas deposits change stratigraphically with depth in the same reservoirs, starting from the Cretaceous, Jurassic, Triassic, Carboniferous up to the Devonian. The paper does not include the documented oil accumulations in the Cretaceous (Cenomanian), Jurassic (Malm). It should be also emphasised that in view of an average geothermal degree, the deposition of natural gas in the form of gaseous or condensate accumulations may generally take place to 3500 m of depth. Thus, we have a few very interesting questions related to the reservoir origin, directions of migration and potential (still undiscovered) dependences resulting from the known conditions of accumulation. The main advantage of the analyses and studies of the reserves is the concrete character of some results of the stratigraphic analysis of the main stratigraphic horizons of the Polish part of the Carpathian Foredeep, illustrated in the form of graphs and listings. The interpretation of the discovered relations is left out for future prospecting or scientific studies.

2

Rozpoznawanie obrazów w prospekcji stref naftowych w cenomanie i malmie synklinorium Nidy

Kotlarczyk J., Jucha S. F., Mastej W., Namysłowska-Wilczyńska B.

Gospodarka Surowcami Mineralnymi

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1999

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T. 15, z. spec.

45-68

PL

Autorzy zastosowali metodę funkcji potencjalnych (metoda rozpoznawania obrazów) w połączeniu z metodami geostatystycznymi do wskazania nowych potencjalnych obszarów akumulacji węglowodorów w mezozoicznym piętrze strukturalnym podłoża zapadliska przedkarpackiego, w jego części obejmującej S przedłużenie synklinorium nidzińskiego. Obiektami badań były otwory wiertnicze opisane zestawem 16 cech informatywnych. Cechy te charakteryzują głębokość i miąższość osadów cenomanu, ich porowatość i przepuszczalność, mineralizację i napory potencjometryczne wód wgłębnych, jak również gradienty tych cech. 16-wymiarowa informacja o każdym otworze wiertniczym została ostatecznie przetworzona w prawdopodobieństwo, że otwór odwiercony w dowolnym punkcie badanego obszaru nawierci złoże. W efekcie wskazano 9 rejonów o podwyższonym prawdopodobieństwie odkrycia złoża.

EN

Sub-Miocene basement of the Carpathian foredeep contains, most probably , unrecognized areas of potential hydrocarbon deposits, occurring in analogous conditions as those already discovered. Particularly rich data come from the area, being the prolongation of Nida synclinorium and refers to Cenomanian and Malmian deposit (fig. 1). This area was intensely explored what resulted in the discovery of several deposits (figs. 1, 2). Usually they occur in the zone where Cenomanian sandstones are wedging out (trap of 1st type), as well as in weathered, porous, karstified Malmian carbonate rocks (trap of 2nd type), also in areas where Cenomanian rocks do not occur (fig. 1). Rarely, hydrocarbon deposits appear in planar domes within the top of thick Cenomanian sandstone sequences (trap of the 3rd type e.g. Rylowa deposit). All these traps are sealed by hardly permeable Upper Cretaceous or Miocene deposits. There are credible premises indicating that in some boreholes, due to imperfect drilling technology, the presence of economic hydrocarbon accumulation could be overlooked and, thus, they were classified as barren. Moreover, vast areas between almost 700 boreholes may also contain undiscovered deposits. As follows from above data, further exploration works are needed, using different methods. As far as mathematical methods are concerned, the most useful can be the pattern recognition methods (PRM), applied jointly with geostatistical ones. The experiments on application of these methods in the area studied is the aim of investigation presented in this paper. In the analyzed case, the application of PRM consist in the calculation of probability of membership of each borehole studied to one of two target classes: to class of wells with economic hydrocarbon accumulation (R) or to those barren (W) i.e. to the computation of P[R] and P[W]. This procedure should be preceded by calculation of probability of membership of each borehole to one of two predictor classes: R* and W*, connected with appropriate target classes R and W. The predictor is the mathematical representation of a given borehole. Predictors are multivariate vectors of features, the values of which are measured in each borehole. The predictor class R* (or W*) is formed by vectors of features measured in boreholes selected from class R (and respectively W) and assented as their patterns. In the analyzed case, pattern boreholes from each deposit were selected for the predictor class R*, more or less proportionally to the number of wells in each deposit (tab. 2). Pattern boreholes for predictor class W* were selected systematically from the whole surface of the areas, situated outside deposits. 16 features were selected from the set of 27 measured (or computed) for the boreholes, the values of which were obtained in the most credible manner (tab. 1). These features were characterizing the depth and thickness of Cenomanian deposits (numbers: 1, 2, 3), their porosity and permeability (numbers: 4, 6), mineralization and potentiometric heads of groundwaters (numbers: 7-10, 17), as weIl as gradients of these teatures (numbers: 22, 23, 25-27). The examination of informativity of these features by means of Puri-Sen-Tamura test of comparison of multivariate means has shown them to form one signiticantly informative combination (fig. 3). The method of potential function in probabilistic version was applied as that of PRM. Consequently, each borehole (pattern and nonpattern, altogether 691) was characterized by one probability value of membership to predictor class R*. The application of block kriging was necessary for the production of maps of the above probability for the whole area. Preliminary geostatistical studies aIlowed to apply the compound variability model to kriging computations (figs. 4, 5). The interpolation of P[R*] probabilities and kriging standard deviations reIated with them are presented in maps (figs. 6, 7). The elaboration of resulting map needs the computation of conditional probabilities (P[RIR*], P[WIR*], P[RIW*], P[WIW*]) (cf. tab. 3). Moreover, the corrections ER and EW proposed by the present authors should be taken into consideration, according to the formula: P[R] = P[R*] (P[RIR*] + ER) + (1 - P[R*]) (P[RIW*] + Ew) where: ER = P[WIR*] P[R'IW] P[R*IR] / P[R*IW] and Ew = P(WIW*] P(R'IW] P(W*IR] / P(W*IW]. These corrections take into account the effect of faulty identification of boreholes (i.e. \delta error) during drilling on the value of the membership probability of a given well to class R. The result of such erroneous identitication is that within the class W there can be incorporated the boreholes forming subclass R' i.e. those, penetrating existing hydrocarbon deposits (fig. 12). The value of this error, expressed as P(R'IW] probability, can be estimated but a priori. The effect of the error in question on prognosis is, in fact, small (tab. 4) but by taking into account the proposed corrections we are increasing the adequacy of recognition. The probability of membership of each point of the area to target class R, is presented in isoline map (cf. fig. 8). All the known deposits considered in our experiment are Iocated in this map within the areas showing the probability higher then 0.5. Moreover, new potential areas of occurrence of deposits were indicated as isolated maxima showing probability more then 0.5. They are representing first of all the traps of 1st type (arrow numbers 1, 3, 5), as well as of 2nd one (arrow numbers 2, 4, 7). Only in one case they represent also 3rd type (arrow number 6). Consequently, there were indicated first of all the regions, characterized by small thickness of Cenomanian deposits, similarly as the vast majority of known deposits that have delivered the patterns. Therefore, other potential deposits, occurring in traps of 3rd type i.e. not related with zones where Cenomanian deposits are thin or lacking, could not be discovered. In order to explain this situation, the second experiment was carried out, in which thickness and the features correlated with it: porosity, permeability and thickness gradient of Cenomanian deposits were eliminated. The result of computation, like in previous experiment, are presented in appropriate maps (figs. 9, 10, 11). Final results of recognition have revealed almost aIl the above indicated new potential zones of hydrocarbon accumulations (excluding maximum no 6) and, moreover two successive, just representing the 3rd type of traps (fig. 11, numbers 8, 9). One of the Iast zones (no 8) showing high probability of occurrence of deposit, amounting to 0.65 has appeared SW of Rylowa deposit. Irrespective of the studies presented here, the borehole Rajsko-1 has, in fact, penetrated a deposit in that zone. This is an important confirmation of reality of results obtained by means of the pattern recognition method.

3

Analiza warunków akumulacji złóż węglowodorów i ich znaczenie dla prospekcji naftowej w basenach Niżu Polski oraz zapadliska przedkarpackiego

Jucha S. F.

Gospodarka Surowcami Mineralnymi

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1999

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T. 15, z. spec.

5-42

PL

W pracy przedstawiono najważniejsze wyniki wieloletnich badań i studiów basenów naftowych Polski w nawiązaniu do analizy i syntezy wybranych zagadnień i zastosowań autorskiej, oryginalnej polskiej metody cyfrowej kartografii naftowej. Uzyskane końcowe rezultaty objaśniono w części tekstowej i graficznej w ujęciu historycznym, organizacyjnym i częściowo metodycznym. Starano się również powiązać i objaśnić zakres i kierunki współpracy z okolicznościową barwną ekspozycją wystawową poświęconą 80-leciu naszej Uczelni.

EN

This paper is a presentation of the results of extensive studies in the framework of methodical researches of rock properties and spatial deposition of layers in the main petroleum basins of the Polish Lowland between the Oder and Bug Rivers. The Polish digital cartography method, often foregoing and original, has been elaborated by the Author (S.F.J.) for the recent 30 years. The concept of digital petroleum cartography is not based on any other patterns partly known from literature or conditionings related to the quality or quantity of information. For this reason in numerous publications it has been labelled as the Polish digital cartography method. The geological concept and the selection of accurate data has been assumed in line with the classical surface cartography and then its principles have been introduced to data processing, software and final caIculations. The eventual pictures have been analysed in co-operation with the top class Polish computer scientists. Among such specialists is the main representative of the specialisation Mr. Ryszard Weinar, PhD who constantly performs the most important activities related to calculations with the use of the electronic graphical apparatuses - first ones made in Poland then also foreign products. The study of the spatial system of layers in petroleum basins required uniformisation of all co-ordinates of the analysed driIling data, not only weIl profiles, but also seismicity profiles, to one Polish system. Initially this was a local system, then the generaIly accepted Borowa Góra system and recently the system 42 (fig. 1, 2, 15a, b, 16a, b). The number of the analysed seismicity and drilling data was presented on the background of stratigraphic horizons in the form of figures Iisted in Tables for the Cretaceous (Cr1), Jurassic (J1), Triassic (T1), Zechstein (P2), Rotliegend (P1) and Carboniferous (C1) and older basement, mainly Devonian (D). The quantitative analysis of the drilling and seismicity data in the Carpathian Foredeep were limited to one stratigraphic border, surface of discordance of the Miocene with the older basement. Thus all the enumerated data were mainly referred to the bottoms of the mentioned geological formations. It has been assumed in the model that they correspond to the surfaces of angular discordances, and considerable facial and Iithological changes for the Zechstein and Rotliegend, which has been proved by the drilling and seismicity surveys. The number of the analysed seismicity and drilling data for each of the enumerated horizons can be thousands. It was important to determine the class of size and num ber of apparent angles of dipping (tab. 1). In the course of the detailed analysis of these unquestionable data, prepared in co-operation with specialists from numerous units of the Polish Petroleum Mining Company, there were prepared digital structural maps (Fig 3-10) for the Upper Cretaceous (Cr2) bottom, the Lower Cretaceous (Cr1) bottom, the Upper Jurassic-Malm (J3) bottom, the Jurassic (J) bottom Iying discordantly on the older basement or other elements also Iying transgressively, e.g. Doggerian (J2), Lower Triassic (mainly T1) or older formations Iying transgressively: Zechstein bottom (P2), Permian bottom (P1) and also bottom of the transgressive Carboniferous (C1 or C2) deposited discordantly on the older basement of the Polish Lowland. In the Carpathian Foredeep special attention was paid to one discordance, being the main angular discordance between the Miocene (M1) and its Mesozoic platform basement: mainly Cretaceous or Jurassic, Palaeozoic: mainly Carboniferous, Devonian or Cambrian, and in the vast area - Proterozoic - in the form of phyllite series building up the Lower San River anticlinorium (fig. 17a, b). After making these maps, initial contour cuts were made every 250 metres to provide the readabiIity of the maps in the scale 1 : 2500 000 and 1 : 4 000 000 for the Polish Lowland. Apart from this, a set of exhibition maps were made in a more detailed scale, mainly 1 : 200 000. The objective of these studies was the analysis of the spatial system of layers over the surfaces of angular discordance, and so determination of the structural Ievels. In the Carpathian Foredeep the spatial system of angular discordance in the Miocene bottom consisted of two parts: between Cracow and Tarnów and Rzeszów and Przemyśl in the east in the scale 1: 500,000 and as exhibition maps in the scale. 1 : 250,000. Based on these digital structural maps, digital depth maps could be made in the scale 1: 2,500,000, usually for four horizons: -1,500 bsl, -2,000 bsI, -3,000 bsl. (fig. 11-14). Thanks to the great number of seismicityand drilling data, the pictures obtained in horizontal planes made it possible to interpret them both in view of potential upliftings or lowerings. Four selected depths stay witllin the range of the most common discovered hydrocarbon deposits. Five depth horizons were selected in the Carpathian Foredeep: -1,000 bsl, -1,500 bsl, -2,000 bsl, -2,500 bsl, -3,000 bsl, but in a more detailed scale l : 500,000 (fig. 18a, b-22a, b). The interpretation of the obtained digital depth maps enabled: 1. Analysis of structural series, 2. Successive uncovering of shallower geological formations, 3. Localisation of perspective areas, 4. Quantitative analysis of anticlinal elevations, synclinal upliftings and monoclinal zones, 5. Differentiation of primary and secondary properties of the spatial system due to, e.g. conditions of sedimantation, style and causes of folding and other deformations of layers caused by, e.g. liquidity of Zechstein salts at greater depths. This elaboration led to the first publication of a fully original methodic approach (not based on literature) in the light of numerous data and activities related to their processing and reliable quantitative interpretation. The most crucial conclusions are as follows: 1. Data preparation, 2. Calculation method, 3. Horizontal depth cuts as a criticism of interpretation maps, 4. Analysis of surfaces of angular discordance, 5. Lack or limitation of discordant, fault tectonics known from many publications. The main advantage of the elaboration lies in the comparison of distribution of the analysed data with the obtained digital structural maps as a significant study of application and check of the Polish digital petroleum cartography.

4

Metodyczna analiza efektywności odkrywania zasobów węglowodorów za pomocą wierceń poszukiwawczych w poziomach stratygraficznych basenów naftowych Niżu Polskiego

Jucha S.F., Pajda R.

Wiertnictwo, Nafta, Gaz

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1998

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R. 15

41-76

PL

W pracy przedstawiono wyniki metodycznej analizy efektywności odkrywania zasobów węglowodorów za pomocą wierceń geologiczno-poszukiwawczych w wybranych poziomach stratygraficznych basenów naftowych Niżu Polskiego w trzech stopniach uogólnienia: a) najbardziej szczegółowym, obejmującym zbiór danych dla dalszych analiz (135 obiektów), b) zbiorczym (5 tabel i 13 zestawień zbiorczych) dla wybranych regionów geologicznych, poziomów stratygraficzno-złożowych oraz rodzajów zasobów węglowodorów w złożach, c) najbardziej ogólnym obejmującym elementy ostatecznych analiz i syntezy wskaźników efektywności poszukiwań i struktury uzyskiwanych węglowodorów w wybranych poziomach stratygraficznych w basenach Niżu Polskiego. Badania objęły następujące poziomy stratygraficzno-złożowe Niżu Polskiego: dolomit górny (Ca2), wapień podstawowy (Ca1) oraz sakson (P1S), karbon (C1+2) i dewon (D2+3) na monoklinie przedsudeckiej, antyklinorium pomorskim, synklinorium mogileńsko-łódzkim i synklinorium lubelskim. Wyróżniono dwa typy złóż: złoża gazowe i złoża ropno-gazowe. Uwzględniono następujące rodzaje zasobów: gaz ziemny, ropa naftowa i gaz ziemny towarzyszący ropie naftowej.

EN

The paper gives the results of methodical analyses of the efficiency of hydrocarbon resources discovery using geological-exploitation drilling in the select stratigraphic horizons of oil basins in the Polish Lowland in three degrees of generality: a) most detailed, constituting a set of data for further analyses (135 items), b) collective, in figures (5 Tables) and graphical (13 listings) for determined geological regions, stratigraphic-reservoir horizons, reservoir types and the types of the according hydrocarbons, c) general, embracing elements of the final analysis and synthesis of efficiency of hydrocarbon resources discovery, in the selected stratigraphic horizons of oil basins in the Polish Lowland. The following stratigraphic-reservoir horizons of the Polish Lowland were analysed: Main Dolomite (Ca2), Bassic Limestone (Ca1) and Saxonian (P1s), Carboniferous (C1+2) and Devonian (D2+3) in the Fore-Sudetes Monocline, Pomeranian Anticlinorium, Mogilno-Łódź Synclinorium and Lublin Synclinorium. Those were gaseous and oil-gaseous deposits. The following resource types were distinguished: natural gas, oil, natural gas appearing together with oil.