Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "silurian" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-12 z 12
    Tytuł:
    Litofacje formacji perspektywicznych dla gazu i ropy w łupkach w utworach ordowiku i syluru na obszarze bałtyckim i podlasko-lubelskim
    Lithofacies of the Ordovician and Silurian formations prospective for shale gas/oilin the Baltic and Podlasie-Lublin areas
    Autorzy:
    Feldman-Olszewska, A.
    Roszkowska-Remin, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/2075505.pdf
    Data publikacji:
    2016
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    litofacje
    ordowik
    silurian
    łupki
    lithofacies
    Ordovician
    Silurian
    shales
    Opis:
    The paper presents a sedimentological analysis of Ordovician (Sandbian–Hirnantian = Caradoc–Ashgill) and Silurian (Landovery–Wenlock, lower Ludlow) claystones and mudstones from the north-eastern (Baltic Basin) and south-eastern (Podlasie-Lublin Basin) parts of the East European Craton. In both basins, formations prospective for shale gas/oil were analyzed: the Sasino Fm., Pasłęk Fm. (including the Jantar Mb.), Pelplin Fm., Udal Fm., Wrotnów Fm. and Terespol Fm. Based on lithological and sedimentological criteria, 34 lithofacies and 11 lithofacies associations have been distinguished. The most promising lithofacies arerepresentedbytheL-1,L-3andL-4associationswhicharecharacterizedbydarkgreycolour, a very low degree or lack of bioturbation, rare sedimentary structures, and common content of small pyrite concretions. They dominate in the Sasino Fm., Pas³êk Fm. (in the Jantar Mb. only) and Pelplin Fm., but are much less common in the Udal Fm., Terespol Fm. and Pas³êk Fm. (excluding the Jantar Mb.).
    Źródło:
    Przegląd Geologiczny; 2016, 64, 12; 968--975
    0033-2151
    Pojawia się w:
    Przegląd Geologiczny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Pozycja stratygraficzna formacji łupków z Widełek w synklinie bardziańskiej (Góry Świętokrzyskie)
    Stratigraphical position of the Widełki Formation in the Bardo Syncline (Holy Cross Mts.)
    Autorzy:
    Malec, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/2075106.pdf
    Data publikacji:
    2014
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    Silurian
    litostratygrafia
    biostratygrafia
    Góry Świętokrzyskie
    lithostratigraphy
    biostratigraphy
    Holy Cross Mountains
    Opis:
    Results of the geological studies carried out in the western part of the Bardo Syncline have revealed the wrong stratigraphic position of the Silurian Widełki Formation, established by Stupnicka et al. (1991) in the Widełki area. This lithostratigraphic unit does not represent the youngest Silurian deposits overlying the greywackes of the Niewachlów Beds in the Kielce region of the Holy Cross Mts. In fact, the claystones with graptolites of theWidełki Formation underlie the greywackes of the Niewachlów Beds and belong to the upper part of the Prągowiec Beds.
    Źródło:
    Przegląd Geologiczny; 2014, 62, 11; 748--754
    0033-2151
    Pojawia się w:
    Przegląd Geologiczny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Litostratygrafia syluru polskiej części obniżenia perybałtyckiego - część lądowa i morska (N Polska)
    The silurian lithostratigraphy of the Polish part of the Peri-Baltic Depression (N Poland)
    Autorzy:
    Modliński, Z.
    Szymański, B.
    Teller, L.
    Powiązania:
    https://bibliotekanauki.pl/articles/2074496.pdf
    Data publikacji:
    2006
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    sylur
    litologia
    litostratygrafia
    palaeografia
    Silurian
    lithostratigraphic units
    lithology
    petrography
    palaeogeography
    Opis:
    The Silurian rocks of the Peri-Baltic Depression area (N Poland) were penetrated by 208 boreholes (Fig. 1). Seven new formal lithostratigraphical units were recognized and defined: The Barciany Nodular Limestones Formation (Lower Llandoverian–Rhuddnian, Aeronian), the Pasłęk Bituminous Claystones Formation with the Jantar Bituminous Black Claystone Member (Llandoverian), the Pelplin Green Claystones Formation (Wenlockian–Ludlovian), the Kociewie Claystones and Siltstones Formation with the Reda Marly Siltstones Member (Wenlockian–Ludlovian) and the Puck Marly Claystones and Siltstones Formation (Ludlovian (Ludfordian)–Pridolian). Some of the units have a character of the allostratigraphical ones sensu „North American...”, (1983) because are bordered by the sedimentary or sedimentary-erosional unconformities. The lithology, stratigraphical position, thickness, paleontological data and spatial relation of the particular units are presented (Fig. 2). Their boundaries have been established and stratotypic sections are proposed. Rock sequences of different Formations have been correlated with lithostratigraphical and genetical equivalents of the adjacent regions of Lithuania and Russia (Kaliningrad District) and also with Denmark (Bornholm) and Germany (western part of the Peri-Baltic Depression).
    Źródło:
    Przegląd Geologiczny; 2006, 54, 9; 787-796
    0033-2151
    Pojawia się w:
    Przegląd Geologiczny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Rola geofizyki wiertniczej w określeniu zasobów gazu ziemnego w łupkach
    Application of wire log analysis for petrophysical evaluation and determination of shale gas reserves
    Autorzy:
    Drop, K.
    Kozłowski, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/2074763.pdf
    Data publikacji:
    2010
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    gaz łupkowy
    interpretacja geofizyki wiertniczej
    łupki
    shale gas
    petrophysical interpretation
    Silurian Shale
    Opis:
    The paper presents differences between conventional and shale gas plays (Tab. 1). Shale gas concept comprises a wide range of reservoirs, from the coalbed to tight gas plays. In Europe, where the shale gas rush has just started, shaly rocks were treated so far as unproductive and high quality data sets necessary for evaluating properties of those rocks are usually missing. Therefore, US shale gas plays like Barnett and Haynesville are widely used as valuable reference tools (Jacobi, 2008; Parker, 2009). Coal, where gas is essentially stored entirely by sorption, represents one end of the unconventional gas spectrum and tight gas sands, where gas is essentially stored by compression only - the other end of that spectrum. In turn, shale reservoirs with gas entrapped by sorption and compression, fill the space between the two endpoints. Differentiation of those two components is one of the primary goals of an analysis program. Shale gas reservoirs are formed by a wide variety of rock types which makes it necessary to use most appropriate technologies to characterize both coalbed and tight gas reservoirs. The current paper concentrates on tools for evaluating petrophysical parameters, most suitable for shale gas plays. In the case of old wells with old fashion Soviet logs, the uncompensated neutron gamma tool was commonly used tool. This was the only porosity reading curve in log suite, "neutron porosity curve" which could be overlaid with natural gamma ray (GR) (Fig. 1). Natural gamma ray curve is a good indicator of organic matter, which adsorbed uranium. Other hydrocarbon signatures can be traced on the basis of SP vs GR, GR vs resistivity. Some of hydrocarbon signatures can be related to TOC from core lab measurements. For contemporary good quality wire line log curves the Passey et al. (1990) method has been applied. This method is based on computation of separation between acoustic transit time and resistivity (R) (Fig. 2). The resulting difference is used to calculate TOC taking into consideration maturity of organic matter which is parameter for a bunch of relationships (TOC vs R). Local calibration R to TOC from cores are required. In order to determine reliable relationships between R, gas contents to TOC, the high technology coring service and sensitive laboratory measurements are necessary. The results of petrophysical analyses are important for estimations of gas resources in shales. The formulas for computation of conventional and unconventional gas reserves are generally similar. However, in the case of the unconventional gas reserves, instead of porosity reservoir storage the rock density is applied, and for determinations of hydrocarbon volume-the gas content is applied in place of hydrocarbon saturation. If European unconventional reservoirs turn to be profitable then continent landscape will also change. The big gas fields would require dense networks of rigs that will have some negative environmental impact. This would require a change in industry structure, as well as in public opinion and legal regulations.
    Źródło:
    Przegląd Geologiczny; 2010, 58, 3; 263-265
    0033-2151
    Pojawia się w:
    Przegląd Geologiczny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Silurian shales of the East European Platform in Poland : some exploration problems
    Autorzy:
    Porębski, S.J.
    Prugar, W.
    Zacharski, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/2075023.pdf
    Data publikacji:
    2013
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    Silurian
    black shale
    shale gas
    unconventional play
    czarne łupki
    gaz łupkowy
    niekonwencjonalna gra
    Opis:
    The pericratonic Silurian shale succession in Poland, despite its reasonably well-constrained geological framework, entails a number of contentious issues that need to be resolved before this emerging shale gas play will enter a stage of successful development. The succession is thought to have originated in a Caledonian foredeep encroaching distally onto a pericratonic shelf ramp. However, the geochemical signature of the mudrocks is consistent with a cratonic rather than orogenic sourcing, the proximal part of the foredeep basin-fill is apparently missing, and the shale succession juxtaposes in part across the Teisseyre-Tornquist Zone against suspected terranes with no evidence of Silurian tectonism. Organic-rich Llandovery– Wenlock shales form a NW-SE striking central belt that is increasingly calcareous toward the craton (NE) and more silty toward the inferred orogen (SW), with the TOC content decreasing in both directions perpendicular to the strike. The TOC trend seems consistent with the deep-downlap model of black shale deposition suggested for many Paleozoic foredeep basins, but does not quite agree with the outer neritic to upper bathyal depths assumed for the shale deposition. Preliminary results from three wells drilled by Orlen Upstream in the Lublin Basin indicate that the Llandovery–Wenlock shales were deposited on a distal shelf ramp sheltered from the craton by shelf carbonate shoals and periodically affected by weak storm-generated currents. The impact of storms on water column resulted in intermittent rises of oxygen content in the otherwise anoxic to dysoxic near-bottom conditions. The prospective interval is dominated by calcite-cemented clayey mudstones showing moderate to good reservoir qualities. It is cut locally by ENE- or NE-dipping, steep fractures favourable for fluid transmissibility, and a NE or SWdirection is most advantageous for artificial fracturing. This interval is capped with a Ludlow calcite-cemented, laminated siltstone that forms a regional correlation marker and shows soft-sediment deformations attributable to gravitational collapse on a NE-dipping paleoslope. If correct, this interpretation might imply the encroachment of orogen-fed clinothem system onto the SW-inclined craton-margin shelf ramp.
    Źródło:
    Przegląd Geologiczny; 2013, 61, 11-1; 630-638
    0033-2151
    Pojawia się w:
    Przegląd Geologiczny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Problem tsunamitów. Dlaczego tak mało jest kopalnych osadów tsunami?
    The tsunamites problem. Why are fossil tsunamites so rare?
    Autorzy:
    Łuczyński, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/2074917.pdf
    Data publikacji:
    2012
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    tsunami
    tsunamites
    palaeotsunamites
    stromatoporoid beds
    Upper Silurian
    Podolia
    tsunamity
    warstwy stromatoporoidowe
    górny sylur
    Podole
    Opis:
    Tsunami is a common phenomenon and one of the most dangerous natural hazards of the modern world. Taking into account the relative high frequency of tsunamis in historical times, we can expect accordingly rich geological records of similar events from fossil formations. However, palaeotsunami deposits are surprisingly rare, mainly because of the difficulty of discerning them from sediments formed by other processes, e.g. storms. Part of the problem lies in the definition of tsunamite, which refers only to the triggering process, and in a different approach while discerning modern and fossil tsunamites. Modern tsunamites are identified by connecting the deposits to a particular historical tsunami event, even if they contain no diagnostic sedimentological features - an approach, which cannot be applied to fossil formations. This can lead to an impression that modern tsunami deposits are much more common than their fossil counterparts, which in turn suggest great intensification of tsunami events in historical times. Lately, a great number ofpapers have been published on sedimentary effects of modern tsunamis. The studies concentrated on land and near-shore areas. Many authors point out that the sedimentary record left by tsunami is commonly surprisingly mean and with a very low preservation potential. When interpreting fossil successions, the most important features that might indicate their tsunamite genesis are: mixing of material derivedfrom various facial zones, evidence of deep erosion and long transport, and association with other symptoms of seismic activity. The stromatoporoid biostromal accumulations in the Upper Silurian ofPodolia are presented here as possible palaeotsunamite deposits. Thick layers of redeposited stromatoporoids within fine-grained peritidal deposits are interpreted as an effect of onshore transport of this relatively light material during high-energy sedimentary events, such as tsunami. In many ways, the stromatoporoid beds resemble modern accumulations oftsunami-derived boulders.
    Źródło:
    Przegląd Geologiczny; 2012, 60, 11; 598--604
    0033-2151
    Pojawia się w:
    Przegląd Geologiczny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Waloryzacja geostanowisk na obszarze projektowanego Geoparku Łysogórskiego w Górach Świętokrzyskich
    Valorization of geosites in the projected Łysogóry Geopark in the Holy Cross Mountains
    Autorzy:
    Fijałkowska-Mader, A.
    Malec, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/2075050.pdf
    Data publikacji:
    2013
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    Cambrian
    Silurian
    Devonian
    Cenozoic
    geosite
    geodiversity
    geotourism
    kambr
    sylur
    devon
    kenozoik
    geostanowisko
    georóżnorodność
    geoturystyka
    Opis:
    The paper presents results of valorization of geosites in the Łysogóry Region of the Holy Cross Mountains, which warrant creation of the Łysogóry Geopark. Numerous geosites of different Paleozoic rocks offer a great educational potential, combining many fields of knowledge, such as geology, geomorphology, paleontology, paleoecology, ancient metallurgy industry and historical monuments. Geodiveristy makes this area very attractive for geotourism.
    Źródło:
    Przegląd Geologiczny; 2013, 61, 3; 165--171
    0033-2151
    Pojawia się w:
    Przegląd Geologiczny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Łupki sylurskie platformy wschodnioeuropejskiej w Polsce : wybrane problemy poszukiwawcze
    Silurian shales of the East European Platform in Poland : some exploration problems
    Autorzy:
    Porębski, S.J.
    Prugar, W.
    Zacharski, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/2075081.pdf
    Data publikacji:
    2013
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    Silurian
    black shale
    shale gas
    unconventional play
    sylur
    ciemne łupki
    gaz łupkowy
    niekonwencjonalna gra
    Opis:
    The pericratonic Silurian shale succession in Poland, despite its reasonably well-constrained geological framework, entails a number of contentious issues that need to be resolved before this emerging shale gas play will enter a stage of successful development. The succession is thought to have originated in a Caledonian foredeep encroaching distally onto a pericratonic shelf ramp. However, the geochemical signature of the mudrocks is consistent with a cratonic rather than orogenic sourcing, the proximal part of the foredeep basin-fill is apparently missing, and the shale succession juxtaposes in part across the Teisseyre-Tornquist Zone against suspected ter- ranes with no evidence of Silurian tectonism. Organic-rich Llandovery-Wenlock shales form a NW-SE striking central belt that is increasingly calcareous toward the craton (NE) and more silty toward the inferred orogen (SW), with the TOC content decreasing in both directions perpendicular to the strike. The TOC trend seems consistent with the deep-downlap model of black shale deposition suggested for many Paleozoic foredeep basins, but does not quite agree with the outer neritic to upper bathyal depths assumed for the shale deposition. Preliminary results from three wells drilled by Orlen Upstream in the Lublin Basin indicate that the Llandovery-Wenlock shales were deposited on a distal shelf ramp sheltered from the craton by shelf carbonate shoals and periodically affected by weak storm-generated currents. The impact of storms on water column resulted in intermittent rises of oxygen content in the otherwise anoxic to dysoxic near-bottom conditions. The prospective interval is dominated by calcite-cemented clayey mudstones showing moderate to good reservoir qualities. It is cut locally by ENE- or NE-dipping, steep fractures favourable for fluid transmissibility, and a NE or SW direction is most advantageous for artificial fracturing. This interval is capped with a Ludlow calcite-cemented, laminated siltstone that forms a regional correlation marker and shows soft-sediment deformations attributable to gravitational collapse on a NE-dippingpaleoslope. If correct, this interpretation might imply the encroachment of orogen-fed clinothem system onto the SW-inclined craton-margin shelf ramp.
    Źródło:
    Przegląd Geologiczny; 2013, 61, 8; 468--477
    0033-2151
    Pojawia się w:
    Przegląd Geologiczny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Graptolites – stratigraphic tool in the exploration of zones prospective for the occurrence of unconventional hydrocarbon deposits
    Autorzy:
    Podhalańska, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/2075025.pdf
    Data publikacji:
    2013
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    graptolites
    black shale
    stratigraphy
    Ordovician
    Silurian
    East European Craton
    graptolity
    czarne łupki
    stratygrafia
    ordowik
    Kraton wschodnioeuropejski
    Opis:
    In connection with the exploration of zones prospective for the occurrence of unconventional hydrocarbon deposits, numerous studies of source rocks have been conducted in Poland. Stratigraphic examinations are among the basic elements. The main group of fossils occurring in shale successions, being a potential source of hydrocarbons, is graptolites. This paper describes the assemblages of graptolites from Ordovician and Silurian deposits and shows their importance for the stratigraphy of shale complexes. Due to their abundance and rapid evolution, graptolites are an excellent tool for biostratigraphic dating, regional correlations and biozonation of rock successions in terms of the high-resolution sequence stratigraphy. The paper presents the significance of taphonomic research of graptolites to identify zones of increased accumulation of hydrocarbons in rocks. It has been found that graptolites are an equally important instrument, in addition to elevated TOC values or increased gamma ray radiation on well logs, that allows identification of potential source rocks for hydrocarbons, including shale gas.
    Źródło:
    Przegląd Geologiczny; 2013, 61, 11-1; 621--629
    0033-2151
    Pojawia się w:
    Przegląd Geologiczny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Graptolity : narzędzie stratygraficzne w rozpoznaniu stref perspektywicznych dla występowania niekonwencjonalnych złóż węglowodorów
    Graptolites : stratigraphic tool in the exploration of zones prospective for the occurrence of unconventional hydrocarbon deposits
    Autorzy:
    Podhalańska, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/2075084.pdf
    Data publikacji:
    2013
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    graptolites
    black shale
    stratigraphy
    Ordovician
    Silurian
    East European Craton
    graptolity
    ciemne łupki
    stratygrafia
    ordowik
    sylur
    platforma wschodnioeuropejska
    Opis:
    In connection with the exploration of zones prospective for the occurrence of unconventional hydrocarbon deposits, numerous studies of source rocks have been conducted in Poland. Stratigraphic examinations are among the basic elements. The main group of fossils occurring in shale successions, being a potential source of hydrocarbons, is graptolites. This paper describes the assemblages of graptolites from Ordovician and Silurian deposits and shows their importance for the stratigraphy of shale complexes. Due to their abundance and rapid evolution, graptolites are an excellent tool for biostratigraphic dating, regional correlations and biozonation of rock successions in terms of the high-resolution sequence stratigraphy. The paper presents the significance of taphonomic research of graptolites to identify zones of increased accumulation of hydrocarbons in rocks. It has been found that graptolites are an equally important instrument, in addition to elevated TOC values or increased gamma ray radiation on well logs, that allows identification of potential source rocks for hydrocarbons, including shale gas.
    Źródło:
    Przegląd Geologiczny; 2013, 61, 8; 460--467
    0033-2151
    Pojawia się w:
    Przegląd Geologiczny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Potencjał występowania złóż gazu ziemnego w łupkach dolnego paleozoiku w basenie bałtyckim i lubelsko-podlaskim
    Shale gas potential of the Lower Palaeozoic complex in the Baltic and Lublin-Podlasie basins (Poland)
    Autorzy:
    Poprawa, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/2074759.pdf
    Data publikacji:
    2010
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    gaz łupkowy
    górny ordowik
    dolny sylur
    zachodni skłon kratonu wschodnioeuropejskiego
    EEC
    shale gas
    Upper Ordovician
    Lower Silurian
    East European Craton
    Opis:
    The Lower Palaeozoic basin at the western slope of the East European Craton (EEC) (Fig. 1) is currently recognized as one of the most interesting areas for shale gas exploration in Europe. The Upper Ordovician and/or Lower Silurian graptolitic shale is here the major potential reservoir formation (Figs. 2, 3) (Poprawa & Kiersnowski, 2008; Poprawa, 2009). Moreover, the Upper Cambrian to Tremadocian Alum shale is an additional target locally in the northern part of the Baltic Basin. These sediments are often rich in organic matter (Klimuszko, 2002; Poprawa & Kiersnowski, 2008; Więcław et al., 2010; Skręt & Fabiańska, 2009), as well as silica. Limited data from two wells in the western part of the Baltic Basin show silica contents up to 60-70% (Fig. 4) (Krzemiński & Poprawa, 2006). The advantage of the Lower Palaeozoic shale from the western slope of EEC is its broad lateral extend (Fig. 1) and relatively quiet tectonic setting. The later is particularly true in the case of the Baltic Basin and Podlasie Depression. Structural development becomes to some extent more complex in the case of the Lublin region, where the Lower Palaeozoic shale appears affected by late Famennian to early Visean block tectonics. Development of the organic rich Lower Palaeozoic shale at the western slope of EEC was controlled by several factors. Very important was here the rate of non-organic detritus deposition (Fig. 5). The other factors included organic productivity of the basin, its subsidence, relative sea level changes, basin bathymetry, geochemical conditions at the sea bottom (especially oxygenation), degree of bioturbation, presence of topographic barriers at the sea bottom, leading to development of isolated anoxic zones, sea currents configuration, and climate changes. Organic matter of the Lower Palaeozoic is characterized by presence of II type of kerogen. Appearance of the organic-rich shale within the Lower Palaeozoic section at the western slope of the EEC is diachronic (Fig. 6). From NW towards east and SE, the intervals richest in organic appear related to systematically younger strata, starting from the Upper Cambrian to Tremadocian, as well as the Upper Llanvirn and Caradoc in the Łeba Elevation (northern onshore Baltic Basin; Fig. 7). In central parts of the Baltic Basin and Podlasie Depression as well as NW part of the Lublin region, the intervals richest in organic matter are found in the Llandovery section, while in the eastern part of the Baltic Basin and SE part of the Lublin region the highest TOC contents are found in the Wenlock. Therefore, depending on location at the western slope of EEC, different formations are recognized as the targets for shale gas exploration. The Upper Cambrian to Tremadocian shale, present only in the northern part of the Baltic Basin, is characterized by very high contents of organic matter, with average value for individual sections usually ranging from 3 to 12% TOC. This shale formation is, however, of very limited thickness, not higher than several meters in the onshore part of the basin (Szymański, 2008; Więcław et al., 2010). In onshore part of the studied area, thickness of the Caradoc shale changes from a few meters up to more than 50 m (Modliński & Szymański, 1997, 2008). Contents of organic matter in these sediments are the highest in the Łeba Elevation zone and the basement of the Płock-Warszawa trough, where average TOC contents in individual well sections range from 1% to nearly 4%. Ashgill rocks are characterized by high TOC contents only in the Łeba Elevation zone, where average TOC values for individual well sections rise up to 4,5% at the most. Llandovery shale has high TOC contents, particularly in its lower part, throughout vast parts of the western slope of EEC. The maximum measured TOC contents in those rocks in Podlasie Depression are nearly 20%. Average TOC values for individual sections of the Llandovery are usually equal 1% do 2,5%, except for the Podlasie Depression, where they may reach as much as 6%. Thickness of the Llandovery shale generally increases from east to west to approximately 70 m at the most. However, in the major part of that area it ranges from 20 to 40 m (Modliński et al., 2006). Thickness of theWenlock sediments is also highly variable laterally, from less than 100 m in SE part of the Lublin region to over 1000 m in western part of the Baltic Basin. Average content of organic matter in individualWenlock sections in central and western parts of the Baltic Basin and the Podlasie Depression usually ranges from 0,5% to 1,3% TOC. In the eastern part of the Baltic Basin and in the Lublin region it is higher, rising to about 1-1,7% TOC. The above mentioned TOC values show the present day content of organic matter, which is lower than the primary one. The difference between the present and primary TOC contents increases along with increasing thermal maturity. It is also highly dependant on genetic type of kerogen. Taking into account the II type of kerogen from the analyzed sediments, it may be stated that in the zones located in the gas window the primary TOC was at least one-half greater than indicated by laboratory measurements. From the shale gas point of view, the basins at the western slope of EEC are characterized by a negative relation between depth at present day burial and thermal maturity (Poprawa & Kiersnowski, 2008). In the zones with burial depth small enough to keep exploration costs at very low level (Fig. 8), thermal maturity of shales is too low for gas generation (Figs. 9, 12a). Maturity increases westwards (Fig. 8) along with depth of burial (Fig. 9). Thus, the potential shale gas accumulations in the western part of the studied area occur at depths too high for commercial gas exploration and exploitation (Fig. 12b). Between of the zone of maturity too low for shale gas development and that where depth of burial is too large for its exploration, there occurs a broad zone of the Lower Palaeozoic shale with increased shale gas exploration potential (Fig. 13) (Poprawa & Kiersnowski, 2008; Poprawa, 2009). In that area, there are shale intervals of relatively high thickness and average TOC exceeding 1-2% TOC (Fig. 7, 10, 12c). Thermal maturity of these rocks appears sufficient for generation of gas (Fig. 9, 10), and results of well tests for deeper-seated conventional reservoirs suggest good quality of dry gas with no nitrogen (Fig. 12c). It should be noted that some gas shows have been recorded in the Lower Palaeozoic shale. Moreover, depth of burial is not too large for commercial shale gas exploration (Fig. 8, 10). Hydrocarbon shows and their composition in the Lower Palaeozoic are strictly related to thermal maturity of the source rock. In the zones of low maturity, these are almost exclusively oil shows documented. Further westwards, in the zone transitional to the gas window area, gas is wet and contains significant contribution of hydrocarbon gases higher than methane.Within the gas window zone, the records are almost exclusively limited to methane shows. Moreover, within the zones of low maturity high nitrogen contents were recorded (Poprawa, 2009). In the zones characterized by thermal maturity in the range from 0,8 to 1,1% Ro and very high TOC contents (over 15% at the most), there is a potential for oil shale exploration. The zones with the highest oil shale potential include eastern Baltic Basin in SW Lithuania and NE part of the Podlasie Depression. Some data necessary for entirely firm estimations of potential shale gas resources of the Lower Palaeozoic complex in Poland are still missing. However, preliminary estimates indicate that these shale gas resources may possibly be classified as gigantic (1,400-3,000 bln m3 of recoverable gas; Fig. 15). For comparison, resources of conventional gas in Poland are equal to 140,5 bln m exp.3, and annual domestic gas consumption is at the level of 14 bln m exp. 3. However, it should be noted that some characteristics of the Lower Palaeozoic complexes indicate increased exploration risk. The average TOC contents are here lower than in classic examples of gas shales, like e.g. Barnett shale. Moreover, in the zone of optimal burial depth (less than 3000–3500 m) thermal maturity is lower than in the case of the Barnett shale core area. An important risk factor is also both a limited amount and limited resources of conventional gas fields in the Lower Palaeozoic complex (Fig. 13). Amount and intensity of gas shows in the Lower Palaeozoic shale are also relatively low, and there is no evidences for presence of overpressure in this complex. In the eastern part of western slope of the EEC, there appears an additional risk factor-arelatively high content of nitrogen in gas.
    Źródło:
    Przegląd Geologiczny; 2010, 58, 3; 226-249
    0033-2151
    Pojawia się w:
    Przegląd Geologiczny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Petrologiczne rozpoznanie materii organicznej rozproszonej w sylurskich łupkach Gór Bardzkich (Sudety)
    Petrological identification of dispersed organic matter in Silurian shales of the Bardo Mts. (Sudetes)
    Autorzy:
    Nowak, Grzegorz J.
    Powiązania:
    https://bibliotekanauki.pl/articles/2075962.pdf
    Data publikacji:
    2019
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    Góry Bardzkie
    Sylur
    łupki
    rozproszona materia organiczna
    bituminy stałe
    refleksyjność bituminów
    Bardo Mts.
    Silurian
    shales
    dispersed organic matter
    solid bitumen
    bitumen reflectance
    Opis:
    The present paper is focused on the petrological characteristics of dispersed organic matter of the Silurian part of the Graptolite Shales from the Bardo Mts. (Sudetes). The most abundant organic component is secondarily altered organic matter represented by solid bitumen. Based on the results obtained by optical microscopy, it was possible to distinguish several types of solid bitumen. They were determined as granular, porous, coke-like, mosaic andfluidal types. All bitumen types are optically isotropic. Bitumen reflectance varies between 1.37 and 1.62%. Based on the % reflectance values, the solid bitumen identified in the studied samples are classified as pyrobitumen.
    Źródło:
    Przegląd Geologiczny; 2019, 67; 183--185
    0033-2151
    Pojawia się w:
    Przegląd Geologiczny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-12 z 12

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies