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PL
Przeprowadzono badania litofacjalne, paleontologiczne i geochemiczne osadów ordowiku górnego i niższego landoweru, pochodzących ze wszystkich stref facjalnych polskiej części paleobasenu bałtyckiego. Strefy te, od skańskiej na zachodzie poprzez centralnobałtoskańską, do litewskiej na wschodzie, reprezentują przekrój środowisk sedymentacji od górnego skłonu i szelfu zewnętrznego do środowisk płytkonerytycznych szelfu wewnętrznego. Stwierdzono znaczące zmiany w środowisku abiotycznym i biotycznym związane z globalnymi zmianami paleośrodowiskowymi, wywołanymi ochłodzeniem klimatycznym i zlodowaceniem Gondwany w późnym ordowiku. Po globalnej destabilizacji ekosystemów nastąpiło ocieplenie klimatyczne, szybka transgresja i postępująca anoksja. Badania litofacjalne potwierdziły regresywny charakter osadowej sukcesji od katu do niższego hirnantu. Maksimum regresji określono na wyższą część starszego hirnantu. Początek transgresji miał miejsce w późnym hirnancie. Stwierdzono spójność zmian litofacjalnych oraz krzywych względnego poziomu morza badanego obszaru z innymi obszarami Bałtoskandii. Spójność ta implikuje, podobnie jak to jest w innych obszarach tego rejonu, że zmiany poziomu morza w późnym ordowiku mają w dużej mierze charakter zmian eustatycznych. Analiza paleontologiczna potwierdziła wpływ globalnych zmian klimatycznych i eustatycznych na przebudowę zespołów biotycznych w późnym ordowiku i wczesnym landowerze. Obecność fauny Hirnantia dokumentuje, podobnie jak w wielu innych rejonach świata, okres ochłodzenia klimatycznego i regresji; jednocześnie datując go na wczesny hirnant. Na podstawie zapisu kopalnego stwierdzono kryzys faunistyczny w późnym ordowiku oraz wyróżniono fazy ewolucyjne graptolitów, związane z późnoordowicko-wczesnosylurską przebudową zespołów. Udokumentowano współwystępowanie graptolitów i skamieniałości śladowych w strefie pogranicza ordowiku i syluru, wskazujące na stopniowo postępującą anoksję środowisk sedymentacji w okresie ocieplenia klimatycznego i transgresji w późnym hirnancie i najwcześniejszym rhuddanie. Badania geochemiczne pozwoliły na określenie zmienności składu mineralnego i chemicznego (w zakresie składników głównych i śladowych) utworów wszystkich stref facjalnych na tle abiotycznych i biotycznych zmian środowiskowych. Do analizy paleośrodowiskowej wykorzystano geochemiczne wskaźniki produktywności, ilości i pochodzenia materiału detrytycznego oraz warunków redoks. Badania te pozwoliły na rekonstrukcje warunków środowiskowych i ich zmian w czasie i przestrzeni. Przeanalizowano skład izotopowy węgla i tlenu w węglanach. Wyniki tych badań oraz porównania z obszarami sąsiednimi wykazały zgodne odchylenia wartości δ13C oraz przeważnie δ18O w kierunku wyższych wartości. Tym samym, potwierdzone zostały zmiany oceanograficzne i ekologiczne w hirnancie wiązane z okresem chłodnym i zlodowaceniem Gondwany. Wykazano, że analogiczny trend zmian izotopowych występuje na całym obszarze basenu bałtyckiego, w zgodności z danymi biostratygraficznymi, co potwierdza chronostratygraficzny potencjał uzyskanych profili izotopowych. Skorelowano wahania poziomu morza, krzywe składu izotopowego węgla i tlenu w węglanach oraz wydarzenia biotyczne w basenie bałtyckim z globalnymi zmianami środowiskowymi późnego ordowiku i wczesnego syluru. Przebudowa zespołów biotycznych i zjawiska abiotyczne zarejestrowane w osadach obniżenia bałtyckiego umożliwiają korelację z innymi obszarami Bałtyki i innych paleokontynentów. Zmiany litofacjalne, paleontologiczne i geochemiczne (w tym izotopowe), obserwowane w osadach z rozległego i zróżnicowanego facjalnie basenu bałtyckiego, stanowią ważne uzupełnienie zapisu zdarzeń późnego ordowiku i wczesnego landoweru. Przeprowadzone badania potwierdzają dużą skalę zmian środowiskowych na Bałtyce, które dobrze wiążą się z globalnymi wydarzeniami klimatycznymi, eustatycznymi i ekologicznymi.
EN
The paper deals with lithofacies, palaeontological and geochemical investigations of Upper Ordovician and lowermost Silurian deposits of all facies zones from the Polish sector of the Baltic Palaeobasin. The zones, from Scanian in the west through Central Baltoscandian to Lithuanian in the cast, represent an array of sedimentary environments from the continental slope and outer shelf to shallow-neritic environments of the inner shelf. The integrated lithofacics, palaeontological and geochemical studies supported the occurrence of changes in abiotic and biotic environments of the Upper Ordovician and lower Llandovery with regard to palacoenvironmcntal changes related to a global climatic cooling and the Gondwanan glaciation, which was followed by a warming and fast marine transgression accompanied by progressing anoxia conditions. Lithofacies studies confirmed the regressive character of the Katian and lower Hirnantian dcpositional succession. The peak regression occurred in the late early Hirnantian. The marine transgression commenced in the late Hirnantian, followed by deposition of deeper marine sediments. The uppermost Hirnantian and Rhuddanian deposits represent a new transgressive-regressive cycle. There is a coherency in the lithofacies changes between the study area and other regions of Baltoscandia. Local relative sea-level curves, constructed for Upper Ordovician and lowermost Silurian sections of the Polish part of the Baltic Depression, well correspond to the sea-level curve proposed for Baltoscandia, thus confirming the trend of relative sea-level changes throughout the Baltic Basin. Therefore, the Late Ordovician-early Llandovery relative sea-level changes in the Polish part of the Baltic Depression can be considered, like in the other regions of Baltoscandia, to have been induced largely by glacioeustatic changes. Sedimentary continuity and gradual facies and ecological changes at the Ordovician/Silurian boundary were proved in some sections in the western part of the Baltic Depression. Palaeontological analysis confirmed the influence of global climatic and custatic changes on the restructuring of biotic assemblages in Late Ordovician to early Silurian times. A faunal crisis is recorded to have occurred in Late Ordovician times. The occurrence of the Hirnantia fauna in borehole sections of both the western and eastern parts of the Baltic Depression reflects, like elsewhere in the world, a glaciocustatic sea-level drop in the early Hirnantian. The research results confirm the presence of evolutionary phases related to the Late Ordovician-early Llandovery restructuring of graptolite assemblages. Chemical composition (TOC, main and trace components) of the deposits and values of geochemical proxies show that geochemistry of the deposits from the western part of the Baltic Basin is more variable as compared to the eastern part of the study area. The docunented variations in redox conditions of the Baltic Basin well correlate with the end-Ordovician global events: better oceanic circulation and bottom water oxygenation in the early Hirnantian, and progressing transgression/anoxia accompanied by a climatic warming in the late Hirnantian and early Rhuddanian. The results of carbon and oxygen isotopic composition analysis in carbonates show a shift in δl3C and most of δ18O values towards higher values. It was proved that a similar trend of C and O isotopic composition changes occurs in| the whole Baltic Depression and, moreover, it is in conformity with biostratigraphic data. This conformity confirms that the isotopic profiles have chronostratigraphic significance. It well corresponds to the oceanographic and ecological changes observed in the Hirnantian, linked with a cool period and the Gondwanan glaciation. The results of research on carbon and oxygen isotopic composition of deposits from the Scanian facies zone arc the first results obtained from deposits of the distal shelf of Baltica. The research results were the basis for correlations of the relative sea-level changes, carbon and oxygen isotopic composition curves in carbonates, and biotic events in the Baltic Basin with global environmental changes of Late Ordovician and early Llandovery times. Thus, the results proved the influence of Late Ordovician climatic fluctuation (climatic cooling and Gondwanan glaciation followed by a climate warming), and related eustatic and ecological changes on the facies, palaeontological and geochemical record of environmental changes in the deposits of the Polish part of the Baltic Depression.
EN
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.
EN
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.
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Content available remote Skamieniałości śladowe w ordowiku strefy Koszalin-Chojnice-nowe dane
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EN
Amoderately rich trace fossil assemblage in the Ordovician rocks of the Koszalin-Chojnice area (NW Poland) has been recovered for the first time. Previously the only evidence of trace fossils was represented by the clusters of small cylindrical pellets assigned to the Tomaculum problematicum [Groom]. The newly discovered trace fossils occur in greyish-brown and greyish-green claystone and silty claystone of Llanvirnian to Lower Caradocian [teretiusculus - multidens zones]. The most diverse and well-preserved trace fossils have been found in the Skibno 1 profile. They are known also from the other deep boreholes: Jamno IG 2, Miastko 1, Polskie Łąki IG 1 and Chojnice 5. The ichnofossil association is represented mainly by fodinichnia of the deposit feeders: Planolites isp. and Chondrites isp. In the multidens zone of the Skibno 1 profile, domichnia of suspension feeders: ? Cylindrichnus isp., ? Bergaueria isp. and Palaeophycus isp. appear. Ordovician ichnofossils from deep boreholes of the Koszalin-Chojnice area differfrom the Nereites ichnofacies which has been identified on the Rügen Island [Germany]. The intervals with trace fossils define the levels of better oxygenation and the presence of domichnia of suspension feeders in the upper part of the Lower Caradocian-a new feeding resources in a more agitated and probably shallower environment.
PL
Przedmiotem pracy jest przedstawienie najnowszych poglądów dotyczących ustalenia granic jednostek biostratygraficznych (poziomów graptolitowych) w interwale granicznym ordowik/sylur jak również problemów związanych z określeniem na ich podstawie granic jednostek chronostratygraficznych. Rewizja schematu stratygraficznego w standardowym profilu Dob's Linn (Szkocja) oraz nowe dane stratygraficzne uzyskiwane ostatnio na podstawie analizy profilów O/S w Chinach stały się podstawą rewizji granicy ordowik/sylur, w myśl której poziom acuminatus proponuje się podzielić na ascensus i acuminatus, gdzie spąg poziomu ascensus wyznacza pierwsze pojawienie się A. ascensus i P. praematurus . Dolna granica poziomu ascensus wyznaczałaby więc spąg rhuddanu i spąg syluru. Dane te są porównywane z najnowszymi wynikami badań autorki dotyczącymi granicy ordowiku i syluru w północnej Polsce (wyniesienie Łeby) i synklinie bardziańskiej.
EN
Despite continuous study and considerably discussion a number of essential problems concerning the Ordovician/Siln rian boundary and its stratotype have been lately raised and the new ideas relevant to the Ordovician/Silurian transition continue to hv expressed. The new data from well preserved and rich in fauna Chinas 'profiles as well as restudy of the Dob 's Linn (Scotland) standard profile caused that a revision to the biostratigraphic definition of the O/S boundary is proposed. According to the newest suggestion the basal of the Silurian is the Akidograptus ascensus Zone which is overlain by the acuminatus Zone. These data are compared with the essential results of the recently investigated profiles from the Łeba Elevation (northern Poland) and Holy Cross Mis.
PL
Przedstawiono zarys lito- i biostratygrafii osadów ordowiku i syluru występujących w sąsiadujących ze sobą, po obu stronach linii tektonicznej Teisseyre’a–Tornquista, strefie Koszalin–Chojnice oraz zachodniej części obniżenia bałtyckiego. Charakterystykę tę dokonano na podstawie usystematyzowania i aktualizacji wcześniej wykonanych badań stratygraficznych, uzupełnionych o nowe dane i uszczegółowienia. Ponieważ rozpoznanie utworów dolnego paleozoiku w strefie TESZ jest dużo słabsze niż na kratonie wschodnioeuropejskim, badania stratygraficzne uzupełniono elementami analizy sedymentologicznej, paleontologicznej oraz mikro- i biofacjalnej ordowiku i syluru strefy Koszalin–Chojnice. W rozwoju lito- i biofacjalnym strefy Koszalin–Chojnice wykazano podobieństwa i różnice w stosunku do obszarów obecnie sąsiadujących: zachodniej krawędzi kratonu wschodnioeuropejskiego i obszaru Rugii, chociaż możliwości porównawcze z tym ostatnim obszarem, ze względu na częściowe mijanie się „sekwencji” stratygraficznej, są ograniczone. W świetle zgromadzonych faktów nie można wykluczyć związków paleogeograficznych i facjalnych między obszarem Koszalin–Chojnice i zachodnią częścią basenu bałtyckiego, szczególnie w sylurze. W ordowiku natomiast stwierdzono pewną odmienność reżimu depozycyjnego w części basenu, którego wypełnienie stanowią osady strefy Koszalin–Chojnice, w stosunku do obszarów sąsiednich: obszaru Rugii i brzeżnej części kratonu wschodnioeuropejskiego. Uzyskane dane wydają się jednak przemawiać za stosunkowo bliskim, choć niekoniecznie bezpośrednim, sąsiedztwem omawianych obszarów w dolnym paleozoiku.
EN
The paper summarizes the general outline of litho- and biostratigraphy of Ordovician and Silurian deposits from the areas of the Koszalin-Chojnice zone and the western part of the Baltic Depression, situated near each other and located on both sides of the Teisseyre-Tornquist Zone. The characterisation is based on a systematisation and updating of earlier stratigraphical studies complemented with new data and details. As the degree of recognition of Lower Palaeozoic deposits along the TESZ is much poorer than in the East European Craton, stratigraphical investigations have been supported by sedimentological, palaeontological, microfacies and biofacies analyses of Ordovician and Silurian deposits from the Koszalin-Chojnice zone. The investigations have shown that both similarities and differences can be observed in the areas which are now situated close to each other: the western margin of the East European Craton and Rügen Island. It may suggest palaeogeographical connections of these areas with both Baltica and Avalonia. In the light of available facts, it cannot be precluded that there were palaeogeographical and facies relationships between the Koszalin-Chojnice zone and the western part of the Baltic Basin, in particular during Silurian times. In this part of the basin which is filled by the Koszalin-Chojnice zone deposits, the Ordovician depositional regime shows its distinctness from the neighbouring areas of Rügen Island and the East European Craton margin. However, the data obtained seem to suggest that the discussed areas were located relatively close to each other during. Early Palaeozoic times, although not necessarily in direct nearness.
EN
A gradual transition from sandy through silty to clayey strata occurs near the Ordovician–Silurian (O/S) boundary in the southern part of Holy Cross Mountains, in the Bardo Syncline. Three graptolite biozones are distinguished for the O/S boundary interval deposits: ?persculptus, ascensus-acuminatus and vesiculosus. The first, rare graptolites appear below “graptolitic shales” in the ?persculptus Biozone. The diversity of the assemblage increases in the next two biozones. An analysis of acritarch frequency shows a decrease of acritarch frequency at the O/S boundary and then a gradual increase in the lower part of the ascensus-acuminatus biozone with a maximum in the vesiculosus Biozone. The taxonomic diversity of the acritarch assemblage shows a similar trend although the maximum of acritarch frequency observed in the vesiculosus Biozone do not coincide the maximum of acritarch taxonomic diversity.
EN
Studies that have recently been carried out by the Polish Geological Survey aim at, among others, deepening and supplementing the knowledge of unconventional hydrocarbon systems in Poland, including petroleum systems of the lower Palaeozoic in the Polish part of the East European Craton and of the Carboniferous in the South-Western Poland. The article presents the main principles and objectives of the research and the results of the project titled “Identification of prospective zones for unconventional hydrocarbon accumulations in Poland, stageI”,which is the only project that uses a wide range of recently conducted regional geology research and laboratory analyses, integrated with geological information derived from newly drilled boreholes. Geological constraints for the occurrence of unconventional hydrocarbon deposits in the Cambrian, Ordovician Silurian and Carboniferous rocks are presented. What is emphasized is the need to continue the work and to extend it to new research directions aimed at petroleum system modelling (e.g.burial history and analysis of hydrocarbon generation), and the need to refine and clarify some of the results obtained, supplementing them with an analysis of the latest data from newly drilled boreholes.
EN
On the 28th of June 2017, the Polish Ministry of the Environment announced the boundaries of the tender areas selected for the third licensing round for concessions for prospection, exploration and exploitation of hydrocarbons. This round is going to be proceeded in the 4th Quarter of 2018 and 1st Quarter of 2019. The geologists of the Polish Geological Survey selected 15 tender areas (promising for discoveries of conventional and unconventional oil and gas fields) based on the geological data resources stored in the National Geological Archive, other published data, as well as the knowledge and experience of employees of the Polish Geological Institute - National Research Institute and the Polish Ministry of the Environment. All selected areas are located onshore. In this article we describe 10 tender areas located in the Gdańsk, Pomerania and Wielkopolska petroleum provinces. Other tender areas situated in the Carpathians (Błażowa, Proszowice W, Rudnik-Lipiny, Wetlina) and in the Lublin Petroleum Province (Ryki) will be discussed in the next publication. Three areas: Wejherowo, Bytów and Braniewo-Miłakowo are located in the northern Poland (Gdańsk Petroleum Province). The exploration targets of these areas are generally related to structural-lithological traps in the Middle Cambrian beds of the Baltic Basin, as well as to unconventional shale oil and gas in the Lower Paleozoic. Seven tender areas are situated in the northwestern Poland (Pomerania and Wielkopolska Petroleum Provinces). Three of them - Chodzież, Piła and Leszno are dedicated to conventional gas deposits in the Rotliegend sandstones and, in some cases, also oil deposits in the Zechstein/Main Dolomite. Excluding the Leszno tender area, chances for tight gas discoveries exist within the Rotliegend sandstones. The exploration target of the Konin tender area is related to possible conventional fields in the Jurassic and Lower Cretaceous beds. In the Pomerania region the exploration target is generally related to conventional hydrocarbon deposits in the Devonian, Carboniferous and Permian (Rotliegend and Zechstein/Main Dolomite). Three tender areas are situated within the region of: Sierpowo, Orle and Chełmno. As a rule, a concession is granted for a period of 10 to 30 years and is divided into 2 phases: 1) prospecting and exploration phase (which lasts from 4 to 5 years and can be extended to another 2-year period), 2) production phase. Every entity interested in obtaining a concession needs to undergo the qualification procedure. We believe that this publication will contribute to better understanding of the offered tender areas and encourage activity in the Polish oil and gas sector.
EN
The paper presents the characteristics of prospective zones identified for the first time within the lower Palaeozoic shale formations occurring in the Baltic-Podlasie-Lublin Basin and within the Carboniferous shale, sandstone, and mixed shale-sandstone complexes (the so-called hybrid complexes) in the basin of south-western Poland. The lateral and vertical ranges of these zones are determined based on specific criteria using the results of various research methods and analyses, i.e.: stratigraphic, sedimentological, mineralogical, petrological and geochemical of organic matter, petrographic and petrophysical, including interpretation of well logs. Archived geological materials and those coming from the boreholes drilled recently in the concession areas were also used. Four prospective zones have been distinguished in the lower Palaeozoic of the so-called shale belt: SP1, SP2, SP3 and SP4. The most prospective area for the occurrence of unconventional hydrocarbon deposits in shale formations is the Baltic region – the Łeba Elevation, where there are all four perspective zones, only partially covering the range of potentially prospective formations. In each of these zones, both liquid and gas hydrocarbons can be expected in this area. Due to the low percentage of organic matter, the lowest hydrocarbon generation potential is attributed to the Lublin region. However, the low values of this parameter are compensated by other parameters, i.e. the considerable thickness and lateral extent of zone SP4 corresponding partly to the Pelplin Formation. In the Carboniferous rocks of south-western Poland, seven prospective zones have been distinguished in four borehole sections. Four of them are “tight” zones in compact sandstones, while the other three zones represent a hybrid type in complexes with mixed lithology. No prospective zones have been defined in complexes with homogeneous shale lithologies. Determination of lateral extents of the identified zones has not been possible due to the scarcity of data on the geological structure and stratigraphy of the Carboniferous succession in the study area
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