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EN
The article analyses the water quality of the Lower Cretaceous aquifer in the Beni-Ounif syncline. To this end, 42 samples were taken for physico-chemical analysis and 28 for microbiological analysis in March, May and October 2017 from 14 sampling points. The results of physico-chemical analysis were processed by multi-variety statistical analysis methods: principal component analysis (PCA) and hierarchical cluster analysis (HCA) coupled to hydro chemical methods: Piper diagram. The PCA allowed us to explore the connections between physico-chemical parameters and similarities between samples and to identify the most appropriate physico-chemical elements to describe water quality. The HCA allowed us to classify the sampling points according to the similarity between them and thus reduce them for the next follow-up analysis. Waters of the syncline are characterized by medium to low mineralization (320 < EC < 7600 μS∙cm–1 and 200 < RS < 4020 mg∙dm–3) and hardness of between 22 and 123°f. Only 19% of the samples show NO3 concentrations exceeding the Algerian standards. Microbiologically, the study reports the presence of bacteria: coliforms (<8 CFU∙0.1 dm–3), Streptococcus D (<1100 CFU∙0.1 dm–3), Clostridium sulphito-reducer of vegetative form (<90 CFU∙0.02 dm–3) and sporulate (<4 CFU∙0.02 dm–3), total aerobic mesophilic flora at 22°C (<462 CFU∙0.001 dm–3) and at 37°C (<403 CFU∙0.001 dm–3). It must be noted that no presence of thermo-tolerant coliforms is observed.
PL
W artykule przedstawiono wyniki analizy jakości wody z poziomu wodonośnego dolnej kredy w synklinie Beni-Ounif. W tym celu pobrano 42 próbki wody do analiz fizycznych i chemicznych oraz 28 próbek do analiz mikrobiologicznych z 14 stanowisk w marcu, maju i październiku 2017 r. Wyniki analiz fizycznych i chemicznych przetworzono za pomocą wieloczynnikowych metod statystycznych: analizy czynników głównych (PCA) i hierarchicznej analizy skupień (HCA) połączonej z metodami hydrochemicznymi, z diagramem Pipera. Analiza PCA umożliwiła zbadanie powiązań między parametrami fizycznymi i chemicznymi oraz podobieństwa między próbkami, a także identyfikację parametrów najbardziej odpowiednich do opisu jakości wody. Wykorzystując HCA, sklasyfikowano stanowiska według ich wzajemnego podobieństwa oraz zredukowano ich liczbę do przyszłych analiz. Wody synkliny charakteryzowały się małą do średniej mineralizacją (320 < EC < 7600 μS∙cm–1 i 200 < RS < 4020 mg∙dm–3) i twardością między 22 i 123°f. Tylko 19% próbek wykazywało stężenie azotanów przekraczające algierskie normy. W badanych wodach stwierdzono obecność bakterii z grupy Coli (<8 jtk∙(0,1 dm3)–1), Streptococcus D (<1100 jtk∙(0,1 dm3)–1), wegetatywnych form (<90 jtk∙(0,02 dm3)–1) i przetrwalników (<4 jtk∙(0,02 dm3)–1) Clostridium oraz całkowitej mezofilnej flory aerobowej w temperaturze 22°C (<462 jtk∙(0,001 dm3)–1) i 37°C (<403 jtk∙(0,001 dm3)–1). Należy dodać, że nie stwierdzono obecności termoodpornych bakterii z grupy Coli.
EN
The Getic Nappe belongs to the Central Dacides or Dacia Mega Unit. Gravity flow deposits were generated by the Lower Cretaceous overthrust and uplift of this unit over the External Dacides. In the Piatra Craiului Syncline (part of the Getic Nappe), such detrital deposits are represented by the Aptian conglomerates and the uppermost Albian-Cenomanian conglomerates. Part of the infill of the syncline consists of a thick pile of NW-SE oriented conglomerates. Sedimentological study documents the presence of an association which consists of three distinct facies types, represented by: massive conglomerates; alternating conglomerates, sandstones and microconglomerates; and fining- and coarsening-upwards conglomerates. These deposits were accumulated through a series of debris flows, and hyperconcentrated or concentrated flows. The entire assemblage represents a complex routing system within submarine channels, an interpretation made by interpreting facies associations, palaeoflow directions and clast fabrics. A large part of this succession was removed by post-Albian erosion. Thus, the interpretation of the depositional system could be as a series of feeder channels or the submarine sector of a fan-delta system representing a foreland basin fill.
PL
Rejon niecki mogileńsko-łódzkiej jest, obok Podhala, jednym z najbardziej perspektywicznych rejonów w Polsce dla efektywnego zagospodarowania zasobów geotermalnych. Wykorzystanie energii geotermalnej w tym regionie powinno w pierwszej kolejności być związane ze zbiornikami dolnojurajskim i dolnokredowym. Obecnie w Poddębicach i Uniejowie eksploatowane są wody zbiornika dolnokredowego. Na różnym etapie zaawansowania występują projekty wykorzystania potencjału energetycznego w rejonie niecki mogileńsko-łódzkiej, w tym w: Kole, Sochaczewie, Sieradzu, Aleksandrowie Łódzkim, Konstantynowie Łódzkim, Łodzi. Istnieją również plany szerszego zagospodarowania wód geotermalnych w Poddębicach i Uniejowie. W celu określenia możliwości budowy nowych instalacji geotermalnych w rejonie niecki mogileńsko-łódzkiej wykonano analizę danych geologicznych oraz reinterpretację podstawowych parametrów hydrogeologicznych dolnokredowego i dolnojurajskiego zbiornika geotermalnego, w tym temperatur i mineralizacji wód oraz wydajności ujęć w obrębie analizowanych zbiorników geotermalnych. Skonstruowanie trójwymiarowego modelu geologiczno-parametrycznego obszaru badań wykonanego w programie Petrel umożliwiało określenie przestrzennego rozkład analizowanych parametrów zbiornikowych. W efekcie tych działań dokonano obliczeń przewidywanej mocy cieplnej instalacji geotermalnych i wskazania miejsc perspektywicznych dla dalszego zagospodarowania zasobów geotermalnych w rejonie niecki. Większy potencjał energetyczny, wynikający głównie z wyższych temperatur wód geotermalnych, związany jest z wodami zbiornika dolnojurajskiego, jednak w przypadku ich wykorzystania należy mieć na uwadze wysoką mineralizacje wód. Lokalizacje perspektywiczne dla wykorzystania wód geotermalnych poziomu dolnokredowego występują na znacznie mniejszym obszarze niż w przypadku zbiornika dolnojurajskiego. Wody tego zbiornika charakteryzują się niższą mineralizacją, ale także niższą temperaturą.
EN
The area of Mogilno-Łódź Trough is, next to Podhale, one of the most prospective areas in Poland for effective management of geothermal resources. The use of geothermal energy in this region should be, first of all, related to Lower Jurassic and Lower Cretaceous reservoirs. At present, the reservoir waters are exploited successfully – in Poddębice and Uniejów – Lower Cretaceous. Projects of using the energy potential of waters from the Lower Jurassic reservoir (Koło, Sochaczew, Sieradz, Aleksandrów Łódzki, Konstantynów Łódzki, Łódź) are at different stages of development. In order to identify the possibilities of setting up new geothermal installations in the area of the Mogilno-Łódź Trough, the analysis of geological and hydrogeothermal parameters for a Lower Cretaceous and Lower Jurassic geothermal reservoir was conducted on the basis of the analysis of archival materials, research works, geological designs and an inventory of operational parameters of already existing geothermal installations. Hydrogeological and geothermal parameters were evaluated, including an estimation of water temperatures and mineralisation, as well as probable discharge of geothermal wells. The construction of a 3D geological-parametric model of the study area, made using Petrel software, enabled the spatial distribution of parameters being analysed, and next, the evaluation of geothermal resources in the Lower Cretaceous and Lower Jurassic reservoirs. As a result of those activities, the thermal power of the geothermal installations was calculated and prospective locations for further utilization (usage) of the geothermal resources were indicated. Considerable energy potential relates to geothermal waters of the Lower Jurassic reservoir, however, if they are used, high TDS should be taken into consideration. Thus a two wells (doublet) system will be advisable. Locations prospective for the use of geothermal waters from the Lower Cretaceous aquifer occur at limited area unlike the Lower Jurassic reservoir. Waters of that reservoir are characterised by a lower mineralisation, but also a lower temperature.
EN
The elemental composition of terrigenous sediments is extremely important for interpreting the depositional conditions of sedimentary basins especially when traditional data are not available or insufficient. For the first time in the published literature, the elemental composition of the Lower Cretaceous Weald Basin (south-east England) is presented via X-ray fluorescence (XRF) and Spectral Gamma-ray (SGR) methods. The concentrations of Zr, Cr, Ni, Rb, and Sr in varying quantities suggest that the sediments may have been sourced from a stable craton while the enriched redox-sensitive elements such as Mo and Co confirm the presence of anoxic and reducing conditions at the sites of deposition. The spectral gamma-ray data show that the sandstone facies are more radioactive than the adjacent mudstone and shale and this trend is consistent with a freshwater origin. The higher quantity of thorium in relation to uranium indicates humid and hot palaeoclimatic conditions at the source areas that favoured intense weathering. The results of these analyses reinforce the importance of the geochemistry of sedimentary rocks as useful tools for understanding the depositional conditions of sedimentary basins.
EN
Benthic foraminifera, tintinnids and calcareous dinocysts provide new important biostratigraphic data on the age of the Raptawicka Turnia Limestone Formation and Wysoka Turnia Limestone Formation of the NiedŸwiedŸ crag geological section in the Polish Western Tatra Mts. Foraminiferal assemblages of shallow- water limestones from the NiedŸwiedŸ section contain some stratigraphically significant species, including Haghimashella arcuata (Haeusler), Protomarssonella kummi (Zedler), Uvigerinammina uvigeriniformis (Seibold & Seibold) and Textulariopsis jurassica (Guembel). Sporadic planktonic microfossils, such as the tintinnid Tintinnopsella carpathica (Murgeanu & Filipescu), calcareous dinocysts (Cadosina minuta Borza, Colomisphaera lucida Borza, C. tenuis (Nagy), C. varia Øechanek and Parastomiosphaera malmica (Borza), have also been identified. On the basis of these microfossil assemblages the lower and middle parts of the NiedŸwiedŸ section was dated as the Lower Tithonian–Barremian. Limestones of the Raptawicka Turnia Limestone Formation section represent peloidal, peloidal-oolitic and peloidal-oolitic-bioclastic facies. Limestones from the Wysoka Turnia Limestone Formation of the NiedŸwiedŸ section was dated as the Upper Barremian–Lower Aptian, based on a specific composition of foraminifera assemblages, that suggest an eroded carbonate platform as a source of Urgonian-type carbonate material. The boundary between the formations occurs within a poorly dated interval (Valanginian–Barremian).
EN
The newly discovered White Mesa tracksite in the Burro Canyon Formation represents a snapshot of a diverse, Lower Cretaceous dinosaur fauna from south-eastern Utah. The tracks were found at a construction site where the sandstone had been bulldozed and broken up. All tracks were found as deep, well-preserved natural casts on the underside of the sandstone slabs. Individual theropod tracks are 19–57 cm in length; one peculiar track shows evidence of a possible pathological swelling in the middle of digit III and an apparently didactyl track is tentatively assigned to a dromaeosaurid. Individual sauropod tracks are found with pes lengths of 36–72 cm, and interestingly, three distinct shapes of manus tracks, ranging from wide banana shaped to rounded and hoof-like. Ornithopods are represented with individual tracks 18–37 cm in length; a sin gle track can possibly be attributed to the thyreophoran ichnogenus Deltapodus. Zircon U-Pb dating places the track-bearing layer in the Barremian, contemporary to the lower Yellow Cat Member of the Cedar Mountain Formation, which has a similar faunal composition based on both tracks and body fossils. This new track-fauna demonstrates the existence of a diverse dinosaurian assemblage in the lower part of the Burro Canyon Formation, which hitherto is not known to yield skeletalre mains.
EN
The objective of the present paper is to show clues which are provided for understanding the development and paleogeographic significance of the Lower Cretaceous carbonate platform sequences in different localities. The results are based mainly on the study of previous works and also on the preliminary results from lithological sections investigated by authors. The Urgonian-type limestone represents a characteristic Barremian and Aptian shallow-water carbonate facies deposited along the northern Tethyan margin. The term Urgonien was established by A. d'Orbigny in 1847 for the reef limestones near Orgon (southern France). The facies encloses massive, light-coloured organodetrital limestones with foraminifers (Orbitolina) and transitional sediments - detrital or siliceous limestones. Among bioclasts, fragments of bivalves (rudists), corals, hydrozoans, bryozoans, small and large foraminifera (Palorbitolina lenticularis, Sabaudia minuta) and algae are the most characteristic constituens. In the Early Cretaceous, the opening of Alpine Tethys was completed and induced the development of carbonate platforms on its northern margin. Urgonian carbonate platforms in the Tethys have been widely studied (e.g. Arnaud & Arnaud-Vanneau 1991, Michalik 1994). Several deposition areas can be distinguished in the Western Carpathians, mainly: the Tatric "Urgonian" Platform (biohermal and lagoonal facies), source of the detritus transported to the Murań Limestone; and the Manin Urgonian Platform prograding into the Bela Unit during the Aptian. Debris from both platforms was transported into adjacent basins and deposited as allodapic accumulations (Misik 1990). The oldest hypothesis on the position of the neritic "Urgonian" Lower Cretaceous limestones of the Manin Unit consisting of Podhorie and Manin formations was summarized by Andrusov (1938). He considered the Manin Unit as an independent nappe unit. Later, based on lithostratigraphic and tectonic features, he characterized it as a succession of Central Carpathian affinity. However, its position and the tectonic style are close to Pieniny Klippen Belt structures (Andrusov 1938, Birkenmajer 1977). From the Urgonian-like facies, which occur in the Klippen Belt and the Peri-Klippen Belt we focused mainly on the Manin Unit in the area of the Strazovske vrchy Mts., the Nizna Unit (Nizna Limestone Formation) (Jozsa & Aubrecht 2008), Benatina Klippe (Schlogl et al. 2004) and also in the Haligovce Unit (Haligovce Limestone Formation), which is usually considered as an equivalent of the Manin Unit. In the Outer Carpathians, the Urgonian-type limestones occur exclusively as exotic pebbles in younger deposits. Urgonian facies in the Western Carpathians shows some different features in comparison with other areas in the Tethys realm; e.g. lack of oolitic and oncolitic limestones, small representation of typical lagoonal facies with miliolids and dasycladaceans. The "reef-tufa" cementation, fenestrae, evaporate minerals are also missing, bauxitization is unknown. They use to be affected by silicification (presence of cherts). Dolomitization is almost missing (Misik 1990).
PL
Na podstawie badań litologicznych, profilowań sedymentologicznych oraz analiz palinologicznych rozpoznano środowiska sedymentacji i palinofacje kredy dolnej w otworach wiertniczych Ciechocinek IG 3, Mszczonów IG 1 i Korabiewice PIG 1. Wykonano dokładną analizę spektrum palinologicznego – stosunku zawartości planktonu do całości palinomorf, ilości fitoklastów w całkowitym kerogenie oraz zawartości materii organicznej. W celu scharakteryzowania palinofacji w analizowanych otworach przeprowadzono korelacje danych palinologicznych z wynikami profilowań sedymentologicznych oraz z obserwacjami litofacjalnymi i paleogeograficznymi. Wyniki badań pozwoliły na ogólne rozpoznanie środowisk sedymentacji i palinofacji w strefie depozycji węglanowo-silikoklastycznej oraz w strefie aktywnej poduszki solnej. Na podstawie zebranego materiału, w nawiązaniu do określonego w badaniach palinofacjalnych spektrum palinologicznego, w profilu kredy dolnej wydzielono następujące środowiska morskie: odbrzeża, przybrzeża dolnego–środkowego, płytkiej zatoki morskiej, laguny i płytkiego szelfu węglanowo-silikoklastycznego. W przypadku braku jednoznacznych cech diagnostycznych środowisko sedymentacji określono jako ogólnie morskie.
EN
Based on lithological and sedimentological logging and palynological analysis, sedimentary environments and palynofacies were identified in the Lower Cretaceous of the Ciechocinek IG 3, Mszczonów IG 1 and Korabiewice PIG 1 boreholes. A thorough analysis of the palynological spectrum was performed, determining the ratio between the amount of palynomorphs and the total of plankton, the amount of phytoclasts in the total kerogen, and the content of organic matter. Palynological data were correlated with sedimentological, lithofacies and paleogeographical data. The research resulted in a general recognition of sedimentary environments and palynofacies in the carbonate-clastic deposition zone and in a zone of an active salt pillow. The following sedimentary environments were identified in the Lower Cretaceous sediments, based on the analysed material and with regard to the palynological spectrum: offshore, lower–middle shoreface, embayment, lagoon and shallow carbonate-siliciclastic shelf. In case of the absence of diagnostic features for exact determination of sedimentary environments, the environments were defined as generally marine.
PL
W publikacji przedstawiono wybrane wyniki analizy statystycznej właściwości zbiornikowych i parametrów złożowych utworów jury górnej-kredy dolnej określone na podstawie wyników testów rurowymi próbnikami złoża (RPZ) oraz badaniami geofizycznymi, przydatne przy opracowywaniu charakterystyki geologicznej złóż węglowodorów w utworach górnej jury-dolnej kredy. Właściwości zbiornikowe (porowatość ogólna, miąższość efektywna) oraz parametry złożowe (przepuszczalność, gradient ciśnienia złożowego i wskaźnik wydobycia wody złożowej) jury górnej-kredy dolnej, usystematyzowano w postaci histogramów, w celu scharakteryzowania ich rozkładu i wyznaczenia wartości średnich. Wyznaczone średnie wartości mogą być wykorzystane przy projektowaniu procesów dowiercania, opróbowania i eksploatacji złóż węglowodorów w utworach górnej jury-dolnej kredy. Wartość ciśnienia złożowego określona na podstawie wyników testów złożowych RPZ stanowi podstawę symulacji złożowych, a także projektowania konstrukcji otworów wiertniczych, technologii dowiercania oraz eksploatacji złoża. Metodami analizy statystycznej wyznaczono równanie regresji liniowej zmian ciśnienia złożowego w funkcji głębokości zalegania skał węglanowych jury górnej-kredy dolnej. Równanie to może być wykorzystywane do prognozowania wartości ciśnienia w danym rejonie wierceń. Cechy produkcyjne badanych poziomów perspektywicznych jury górnej-kredy dolnej oceniono na podstawie zmian wskaźnika wydobycia wody złożowej (wydatek przypadający na jednostkę depresji ciśnienia) w funkcji miąższości efektywnej. Uzyskana korelacja pozwala na prognozowanie wskaźnika wydobycia wody złożowej na podstawie miąższości efektywnej w badanych utworach. Cechą skał zbiornikowych, od której w znacznym stopniu zależy wielkość wskaźnika wydobycia tak wody złożowej, jak też i węglowodorów, jest ich przepuszczalność. Zróżnicowane zależności pomiędzy porowatością i przepuszczalnością występujące w skałach węglanowych są często przyczyną trudności i niejednoznaczności w interpretacji wyników testów złożowych. Metodami analizy statystycznej stwierdzono – dla wybranego obszaru poszukiwań naftowych – zadawalającą korelację między przepuszczalnością efektywną dla wody określoną testami RPZ, a porowatością oszacowaną na podstawie pomiarów geofizyki wiertniczej, nadającą się do prognozowania wartości przepuszczalności skał jury górnej-kredy dolnej.
EN
This article presents selected results of statistical analysis of reservoir properties and reservoir parameters of the Upper Jurassic-Lower Cretaceous formation in the Carpathian Foredeep. Reservoir properties and parameters were based on the results of drillstem tests (DST) and geophysical surveys. These results allowed for geological characterization of hydrocarbon deposits in the Upper Jurassic-Lower Cretaceous formations. Reservoir properties (total porosity, effective thickness) and reservoir parameters (permeability, reservoir pressure gradient, and water production coefficients) of the Upper Jurassic-Lower Cretaceous formation have been arranged in the form of histograms in order to define the distribution of average values. Average values can be used in drill up operations, well tests, and exploitation of hydrocarbon deposits in the Upper Jurassic-Lower Cretaceous formation. Methods of statistical analysis determined the linear regression equation of reservoir pressure changes as a function of Upper Jurassic-Lower Cretaceous carbonate formation depth. This equation can be used to estimate the reservoir pressure in the drilling area. Production parameters of the geological formation have been examined based on changes in the water production coefficient (flow rate per unit pressure depression), which can be predicted as a function of the effective thickness of the tested formation. Water production coefficient as well as hydrocarbons production coefficient depends largely on reservoir rocks permeability. The relationship between porosity and permeability in carbonate rocks often causes difficulties and ambiguities in the interpretation of reservoir test results. This analysis, however, found a satisfactory correlation between the effective water permeability from DST tests and porosity estimated from well logs in the selected area of petroleum exploration. This correlation will be suitable for predicting the permeability of the Upper Jurassic-Lower Cretaceous formation.
EN
Sedimentary environments and palynofacies were identified in the Lower Cretaceous of central Poland. The study was based on lithological observations, sedimentological logging and palynological investigations in the following boreholes: Poddębice PIG2, Koło IG3 and IG4, Wągrowiec IG1, Sarnów IG1, Ciechocinek IG3, Mszczonów IG1, Korabiewice PIG1, Człuchów IG2, Klosnowo IG1 and Tuchola IG1. Palynological observations were correlated with sedimentological, lithofacies and paleogeographical data. Sedimentary environments and palynofacies were analysed in the vertical section, and spatially in different areas: in the central basin area, in the carbonate-clastic deposition zone, in the transitional zone (deltaic sedimentation) and in a zone of an active salt pillow. The following sedimentary environments were identified in the Lower Cretaceous: upper shoreface and lower-middle shoreface with transitions to an offshore-open marine shelf, delta (?delta front) passing up into distributary channel fills on a delta plain, presumed barrier and shallow-marine embayment, lagoon and shallow carbonate-siliciclastic shelf. In case of the absence of diagnostic features for exact determination of sedimentary environments, the environments were defined as generally marine or transitional (probably deltaic). A maximum flooding surface has been identified in the Poddębice PIG2 section, represented by a thin dark-grey marl bed which seems to be dated at the Berriasian/Lower Valanginian transition. The relationships between sedimentary environments and the characteristics of the palynofacies spectrum were determined, and a palynofacies pattern for the Lower Cretaceous of central Poland was proposed in a tabular form.
EN
The turbiditic to hemipelagic, fine-grained deposits of the Hradiště Formation (Hauterivian, 132 Ma) to the Lhoty Formation (Albian–Cenomanian, 99 Ma) in the western part of the Silesian Nappe (Polish Outer Car- pathians) were studied mineralogically and geochemically to determine if the main factors controlling the chemistry of the sedimentary material can be attributed to provenance, or to post-depositional processes. A high degree of weathering of the source rocks is indicated by the chemical index of alteration (CIA) that varies from 75.98 to 89.86, and Th/U ratios (~4 with outliers at 1.85 and >6). The cooccurrence of rounded and unabraded grains of zircon and rutile, the enrichment in Zr and Hf, as well as the high Zr/Sc ratios suggest that the Hradiště and Veřovice Formations contain recycled material. Plots of La/Th versus Hf and Th against Sc show that samples occur in the field of felsic and mixed felsic/basic sources. On a ternary La–Th–Sc diagram, all of the sediments studied are referable to the continental island-arc field. The European Plate, as an alimentary area, has a mosaic structure consisting of Cadomian and Variscan elements. The Proto-Silesian Ridge was detached from the continent, because of rifting. Therefore, it could have corresponded to a continental island arc. The concentrations of Fe and trace metals (e.g., Mo, Au, Cu) in the Veřovice Formation and silica and potassium additions to the Veřovice and Lhoty Formations, as well as the fractionation of REE, and Nb, Ta, Zr, Hf, and Y can be explained by the action of basinal brines. The fluids were of hydrothermal origin and/or were released, owing to the dewatering of clay minerals. Diagenetic processes could have exerted a greater influence on sedimentary rock chemistry than the provenance and sedimentary processes. A distinction between primary, terrigenous elements and those changed diagenetically is necessary for the reliable determination of provenance.
EN
New stratigraphic and palaeoenvironmental data are presented for the northeastern part of the Trento Plateau (Puez area, Southern Alps, Italy). The studied section corresponds to the upper Hauterivian Balearites balearis and "Pseudothurmannia ohmi" ammonite zones and normal palaeomagnetic chron upper M5. A c. 30-cm-thick bed is identified as the equivalent of the Faraoni Level, based on its position within the Pseudothurmannia mortilleti Subzone, the composition of its ammonite fauna and the peak of a minor positive trend in the [delta]13 Cbulk record. Microfacies and geochemical proxies compare well with those of the southeastern part of the Trento Plateau and indicate palaeoceanographic continuity along the eastern margin of the plateau. The abundances of radiolarians and nannoconids suggest a turnover in the trophic structure from eutrophic conditions around the Faraoni Level equivalent to oligotrophic conditions. Low organic matter and sulphur content and frequent bioturbation indicate a well-oxygenated environment. Ammonite diversity and life-habitat groups document the influence of sea level on the plateau: while epi- and mesopelagic ammonites occur commonly during sea-level highstands, all life-habitat groups become reduced during a sea-level lowstand in the Spathicrioceras seitzi and P. ohmi subzones. The Faraoni event is heralded by a faunal turnover expressed as the diversification of epipelagic ammonites. Palaeoenvironmental conditions along the eastern margin of the Trento Plateau during the Faraoni event contrast with those of the organic-rich black shales in the west. A re-evaluation of the depositional model based on the new results suggests a general water depth of 300-500 m for the plateau. The severe reduction of mesopelagic ammonites during the sea-level lowstand indicates a shallowing towards the epi-/mesopelagic boundary. During the Faraoni event, the eastern areas of the Trento Plateau were located at the upper limit of the oxygen-minimum layer and were thus only occasionally affected by oxygen depletion, whereas the western areas were located well within the upper part of the oxygen-depleted layer.
EN
The results of semi-quantitative and qualitative studies of nannofossil assemblages in dark to light grey, rhythmically bedded, calcareous mudstones of the Upper Cieszyn Beds, Silesian Nappe of the Outer Carpathians are presented. The vertical variation in the carbonate content of these mudstones and changes in the composition of nannofossil assemblages, as well as the Shannon diversity index (SI), result from humid-arid climate changes, driving the trophic conditions of surface waters and nannoplankton biocalcification. These changes were control- led by the variable influences of both the Tethyan and Boreal provinces. The light grey mudstones were deposited during the dominance of warm waters from the Tethyan realm and some nannoconids, typical of the warm, stratified water of lower palaeolatitudes, occur here. The dark grey mudstones represent influences of the Boreal province, indicated by the appearance of Crucibiscutum sp. and a generally higher biodiversity demonstrated by SI. Climatic changes affected the stratification of surface water, expressed also by different linear fits for pairs of SI, Watznaueria barnesiae and Rhagodiscus asper. On the basis of the presence of Eiffellithus striatus, E. windii and signals of both Tethyan and Boreal influences. the section studied represents the uppermost Valanginian– lowermost Hauterivian boundary interval, i.e., the upper part of the BC5/BC6 nannofossil zones, related to the furcillata-radiatus ammonite zones.
PL
W pracy przedstawiono charakterystykę geologiczną i geoelektryczną ośrodka geologicznego w rejonie Grabownica Starzeńska - Humniska - Brzozów w Karpatach Wschodnich na podstawie danych elektrometrii otworowej i danych geologicznych z otworów. Dla wybranych czterech otworów wiertniczych wykorzystano dane elektrometrii otworowej i obliczono krzywe syntetyczne sondowań TDEM (Time Domain ElectroMagnetic Method). Obliczone krzywe sondowań przeanalizowano pod względem możliwości kartowania struktur wysokooporowych, interesujących ze względu na złoża węglowodorów. Wykonano interpretację 1D krzywych sondowań TDEM zlokalizowanych wzdłuż profili przebiegających przez otwór złożowy Humniska Brzozów-7 z wykorzystaniem algorytmu Occama. Wykonano interpretację kompleksową na tych profilach pod kątem możliwości kartowania złóż ropy naftowej i gazu ziemnego metodą TDEM.
EN
The paper presents the geologic and geoelectric characteristics of the Grabownica Starzeńska - Humniska - Brzozów area (Polish Eastern Carpathians) based on electric logs and downhole geologic data. Synthetic TDEM sounding curves were calculated based on electric log data from four boreholes from the study area. The synthetic sounding curves were analysed from the point of view of possible interpretation of high-resistivity layers that could be prospective for oil and gas exploration. The 1D Occam interpretation of chosen TDEM soundings from profiles that ran across the Humniska Brzozów-7 borehole, was performed. The integrated data interpretation was made to estimate the capability of TDEM method to map hydrocarbon deposits at the study area.
EN
The Upper Jurassic–Lower Cretaceous carbonate sediments developed in a narrow, Ukrainian part of the basement of the Carpathian Foredeep show high facies diversity. Based upon thin section studies, the authors identified eleven principal microfacies varieties. Three main stages of development of carbonate platform were distinguished: (i) Oxfordian–Early Kimmeridgian, (ii) Kimmeridgian–Tithonian, and (iii) Berriasian–Valanginian. The Oxfordian sediments are rather thin and represent both the outer and inner, distally steepened ramp facies. In the Late Kimmeridgian and, mainly, in the Tithonian, the intensive growth of rimmed platform took place with distinct zones of peritidal, margin barrier and platform slope, bearing calciturbidite facies. Development of the rimmed platform was controlled by synsedimentary tectonic movements along faults rejuvenated southwest of the Holy Cross Mts. Fault Zone. In the Berriasian–Valanginian, the dominant process was sedimentation onto not-rimmed platform controlled by small sea-level changes. Both the facies development and literature data indicate that the Late Jurassic sedimentation in the Ukrainian part of the Carpathian Foredeep basement shows considerable differences in comparison to that of the Polish part. In the studied successions, large Oxfordian microbial-siliceous sponge reef complexes, known from the Polish part of the Carpathian Foredeep basement and other areas in Europe, were rare. In the study area carbonate buildups were encountered mainly in the intervals representing the Upper Kimmeridgian–Tithonian where small, microbial-sponge and microbial-coral biostromes or patch-reefs were formed. Their growth was presumably restricted to a narrow zone of the upper slope, close to ooidal-bioclastic margin platform facies. In the Polish part of the Carpathian Foredeep basement, the Late Jurassic sedimentation took place on a vast, homoclinal ramp while in the Ukrainian part it proceeded on a narrow, distally steepened ramp and rimmed platform with distinct marginal platform barrier. Similar platform facies distribution in both regions appeared mainly in the Early Cretaceous, although with some stratigraphical differences. The facies distribution of the Upper Jurassic sediments was closely controlled by the block structure of the basement and by orientation of the main, transcontinental Holy Cross Mts. Fault Zone, which supports the opinion on its activity in the Mesozoic era. The Ukrainian part of the Carpathian Foredeep basement located over the Palaeozoic Kokhanivka Block, between the Krakovets and Holy Cross fault zones, includes predominantly the slope, marginal and inner platform facies. Facies observed over the Palaeozoic Rava Ruska Block (south-western part of the East-European Platform), between the Holy Cross and Rava Ruska fault zones, represents mainly the inner platform and the peri-shore deposits.
EN
A comparative sedimentological analysis of the Upper Jurassic–Lower Cretaceous deposits carried out on drill-cores from the southern part of the Carpathian Foredeep allowed us to distinguish thirteen main microfacies types. The results of microfacies analyses and stratigraphical data made it possible to propose a lithological subdivision of the southern part of the Upper Jurassic and Lower Cretaceous sediments of the Carpathian Foredeep basement between Kraków and Rzeszów. In the analysed wells, three main sedimentary complexes were distinguished, embracing the following intervals: (i) Callovian–Oxfordian, (ii) Kimmeridgian and (iii) Tithonian– Berriasian–Valanginian. The Oxfordian, Kimmeridgian and Tithonian deposits represent the outer – mid homoclinal ramp facies, whereas the Berriasian and Valanginian deposits belong to the inner homoclinal ramp facies. Complexes of microbial-sponge reefs, with a distinct relief, could be recognised in the Upper Oxfordian sediments only. The development of these buildups took place in a basin typified by diversified morphology, determined by the block-type structure of the Palaeozoic basement and synsedimentary tectonics, which brought about substantial variability in thickness of the Oxfordian sediments. At the end of the Oxfordian, large complexes of the reef facies were replaced mainly by microbial-sponge and microbial-coral biostromes developed during the Kimmeridgian and Tithonian. In the principal part of the studied area (except the western part of the described fragment of the Carpathian Foredeep; Kraków area) during the Kimmeridgian, Tithonian, Berriasian and Valanginian, sedimentation occurred in a basin typified by homogeneous morphology, which resulted in a wide extent and comparable thicknesses of the distinguished facies types. In the studied sections, indications of partial or complete dolomitization were observed in a large part of the sediments. Four generations of dolomite document a complex diagenetic history with multiple episodes of dolomite formation: from early diagenetic environment to late burial conditions.
EN
The Upper Hauterivian to Lower Barremian Agua de la Mula Member of the Agrio Formation (Neuquen Basin, Argentina) was studied applying an integrated stratigraphic approach and facies analysis. The ammonite biostratigraphy of the member has been improved based on bed-by-bed collecting. The already defined biozones (Spitidiscus riccardii, Crioceratites schlagintweiti, Crioceratites diamantensis and Paraspiticeras groeberi) were recognized, precisely related to the succession, and further refinement was proposed. Sequences of different order are built by stacked starvation/dilution (s/d) sequences, regarded here as sixth-order sequences with only two components that can be unequivocally distinguished: the lower starvation hemisequence and the upper dilution hemisequence. Pro- and retrogradational stacking pattern of s/d sequences define supra-ordinate sequences. The sequence-stratigraphic analysis resulted in the subdivision of the member into four main depositional sequences (dsAM-1 to -4) and several subordinate sequences. Previously published sequence stratigraphic charts of the Neuquen Basin did not relate sedimentary sequences to biozones, and are hence not comparable to the scheme presented here and other charts. Our study shows a good agreement with the sequence-chronostratigraphic scheme of european basins, thus arguing in favour of a predominantly eustatic control on sequence development during the Late Hauterivian to early Barremian. A latest early Barremian age is proposed for the almost ammonite-barren upper part of the Agrio Formation, based on correlations of sequence boundaries.
EN
During the Early Cretaceous a central part of the Carpathian Foreland was situated in the Peri-Tethys area. That zone was located on the SW margin of the East European Craton and it was adjacent to the Tethys basins in the south. Impact of those both zoogeographic provinces (the Boreal Sea and the Tethys Ocean) is easily noticeable in assemblages of microfauna. Character of sedimentation in the Early Cretaceous basin of the Carpathian Foreland is connected mainly with changes of the sea-level as well as tectonic activity of this region. The stratigraphy and facies data are based on near two hundreds wells profiles. Detailed sedimentological profiles and photographic documentation of the Upper Jurassic and the Lower Cretaceous deposits from about 50 boreholes were done as well as micropalaeontological and microfacial studies of core samples. The presented work is an attempt of unification and formalization of lithostratigraphic units’ nomenclature. Two boreholes: Zagorzyce-7 andWiewiórka-4 were suggested as stratotype sections of distinguished formations. Jurassic–Cretaceous boundary is probably situated within limits of Ropczyce formation in this area. Three formations have been distinguished in the profile of Lower Cretaceous above Ropczyce formation: Zagorzyce limestone-marl formation (Berriasian age), Dębica marl and organodetritic limestone formation (Valanginian) andWiewiórka limestone formation (Late Valanginian-Hauterivian). The most marked erosion surface is recorded between Zagorzyce and Dębica formations. We suppose that hiatus including a large part of Lower Valanginian profile is connected with that erosion surface. It could be refered to a rapid fall of the sea-level in the Tethys Ocean, noticed inter alia in theWestern Carpathians and the Northern Calcareous Alps. The known existing thickness of the Lower Cretaceous sediments in the middle part of Carpathian Foreland (total of three formations: Zagorzyce fm., Dębica fm. andWiewiórka fm.) rises to 188 m in Zagorzyce-1 well.
EN
Microfacies studies show that the Upper Jurassic-LowerCretaceousshaliow-water, carbonate sedimentsof the SE Poland are rich in microfossils that supply additional data for stratigraphical and paleoenvironmentai interpretation of formerly described subdivisions. Local equivalent of the European sponge megafacies (the Kraśnik Fm.) contains characteristic microfossils Globuligerina oxfordiana and Colomisphaera fibrata. Foraminiferal species Afoeoseptajaccardi, Labirynthina mirabilis andMesoendothyra izjumiana identified in the Upper Jurassic subdivisions (the Betżyce and Glowaczow formations) are known from Oxfordian-Kimmeridgian carbonate platforms of the Meditetranean Tethys. The transitional (Tithoman/Berriasian) characler of the peri-reefal Babczyn Fm. is documented by occurrence of foraminifera (Protopeneroplis ullragranulata, Monsalevia salevensis) and caicareous dinocysts (Carpistomiosphaera tithonica, Stomiosphaerina proxima). The ageof the siiiciclastic Cieszanów Fm. is based on theEarly Cretaceous foraminifera (Meandrospira bancilai, Pfenderina neocomiensis, Stomatostoecha condensa) and caicareous dinocysts (Carpistomiosphaera valanginiana, Colomisphaera conferta, Stomiosphaera wanneri).
PL
Badania mikrofacjalne utworów górnej jury i dolnej kredy południowo-wschodniej Polski wykazały, że utwory te zawierają liczne mikroskamieniałości, w sposób znaczący uzupełniające interpretacje wiekowe i paleośrodowiskowe wydzieleń litofacjalnych. Lokalny odpowiednik europejskiej megafacji gąbkowej – formacja kraśnicka - zawiera charakterystyczne gatunki: Globuligerina oxfordiana i Colomisphaera fibrata. Stwierdzone w utworach górnej jury (formacje bełżycka i głowaczowska) gatunki Alveosepta jaccardi, Labirynthina mirabilis i Mesoendothyra izjumiana znane są z węglanowych utworów oksfordu i kimerydu śródziemnomorskiej Tetydy. Przejściowy (tyton/berias) charakter peri-rafowej formacji z Babczyna określa występowanie otwornic (Protopeneroplis ultragranulata, Monsalevia salevensis) i wapiennych dinocyst (Carpistomiosphaera tithnonica, Stomiosphaerina proxima). Wiek silikoklastycznej formacji z Cieszanowa wyznacza obecność wczesnokredowych otwornic (Meandrospira bancilai, Pfenderina neocomiensis, Stomatostoecha condensa) i wapiennych dinocyst (Carpistomiosphaera valanginiana, Colomisphaera conferta, Stomiosphaera wanneri).
PL
Zbadano piaskowce pochodzące z 15 otworów wiertniczych. Reprezentują one głównie arenity oraz waki kwarcowe i sublityczne. Osady te składają się przede wszystkim z ziaren kwarcu mono-i polikrystalicznego, litoklastów, skaleni i łyszczyków. Lokalnie obserwuje się wzrost udziału glaukonitu i Fe-ooidów. Piaskowce uległy procesom diagenetycznym, głównie kompakcji, cementacji i rozpuszczaniu. Rozpoznano efekty kompakcji mechanicznej. W wyniku cementacji powstały głównie minerały węglanowe, ilaste, żelaziste i fosforanowe. Cementy węglanowe występują obficiej od innych. Kalcyty zawierają zmienne domieszki Fe. Minerały syderytu mają skład syderoplesytu. Ponadto rozpoznano związki żelaza: getyt, hematyt oraz piryt. Wśród autigenicznych minerałów ilastych stwierdzono glaukonit, berthieryn i kaolinit. Nodule fosforytowe obecne w osadach górnego albu są zbudowane z frankolitu. Większość minerałów powstała podczas eodiagenezy. Mniej liczne skutki cementacji nastąpiły w etapie mezodiagenezy, gdy osady zostały głębiej pogrzebane. Piaskowce uległy procesom telodiagenezy podczas tektonicznej inwersji obszaru badań. Procesy kompakcji i cementacji spowodowały ograniczenie przestrzeni międziarnowej. Podczas rozpuszczania ziaren kwarcu i skaleni utworzone zostały wtórne pory.
EN
The investigations were carried out on sandstones from 15 boreholes. The rocks are represented chiefly by quartz and sublithic arenites and wackes, and composed mostly of mono-and polycrystalline quartz grains, lithoclasts, feldspars and micas. Fe-ooids and glauconite are locally observed. The sandstones have undergone diagenetic processes, mainly of compaction, cementation and dissolution. Effects of mechanical compaction were identified. As a result of cementation processes, carbonate, clay, iron and phosphatic minerals were formed. Among these carbonate cements occur abundantly. Calcites contain admixture of Fe. Siderites show a composition of sideroplesite. Authigenic clay minerals are represented by glauconite, berthierine and kaolinite. There are also iron compounds: goethite, hematite and pyrite. The Upper Albian deposits contain phosphatic nodules composed of francolite. Most of the minerals formed during eodiagenesis. Less frequent effects of cementation occurred during mesodiagenesis when the deposits were buried to larger depths. The sandstones were subjected to processes of telodiagenesis during tectonic inversion of the study area. Compaction and cementation processes resulted in reduction of intergranular space. During dissolution of quartz and feldspar grains, secondary pores were formed.
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