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EN
This paper focuses on the variations of lignite ash along selected sections and mining walls from three lignite opencast mines in central Poland. They are owned by the Konin Lignite Mine, where the first Mid-Polish lignite seam is being mined to produce electricity. Ash content in lignite is important because ash lowers the calorific value of the lignite. The results obtained are based on 266 samples of lignite collected from the Drzewce, Tomisławice, and Jóźwin IIB opencasts. All samples were tested according to ISO 1171 standard procedures, that is, they were first burned at a temperature of 850°C, then the ash content was determined on a dry basis (Ad ), before the basic statistical parameters were calculated. The studied lignite seam is characterised by a variable distribution pattern of ash both along selected vertical sections and lignite walls, as well as between the three opencasts. The ash content of individual samples ranged from 6.5 to 69.8 wt%, while the average content in opencast mines varied from 9.7 to 17.6 wt%. The coefficient of variation is large (80.23–96.33%) in the case of the Drzewce and Tomisławice, and low to average (14.53–37.75%) in the case of Jóźwin IIB. Significant ash enrichment of some beds is interpreted in this article as a consequence of floods occurring in a Mid-Miocene mire (backswamp), but also of chemical precipitation. When lignite is burned to generate electricity, a relatively large amount of ash is produced. Therefore, recognition of ash content in lignite, in addition to the chemical composition and phase of ash, is recommended to better protect the environment. At the first stage of protection, it can be best achieved by analysing field samples for ash content.
EN
Seven Middle Miocene (Upper Badenian to Lower Sarmatian) sedimentary sections of the Central Paratethys, two from the Polish Carpathian Foredeep Basin (PCFB) and five from the Eastern Carpathian Foreland Basin (ECFB) of Romania and the Republic of Moldova have been analysed micropalaeontologically to better constrain the Badenian-Sarmatian Extinction Event, characterized by significant taxonomic impoverishment of both foraminifers and ostracods. Ourstudies show significant palaeoenvironmental changes in the basin including depth, salinity, oxygenation, and organic matter flux. The occurrence of moderately diverse planktonic foraminifera (Globigerina, Globigerinita, Globorotalia, Trilobatus, Orbulina, Velapertina) in the Upper Badenian deposits of the PCFB as well as in the ECFB and their rarity in the lowermost Sarmatian indicate an almost fully marine environment during the latest Badenian, followed by a significant regression and possible appearance of much more restricted marine conditions across the boundary. The taxonomic composition of the Sarmatian foraminifera, ostracoda and calcareous nannofossils indicate that during this interval the salinity fluctuated strongly, with the water regime varying from brackish to normal marine. In addition, the identified micropalaeontological assemblages identified show palaeoenvironmental similarity across different basins of the Central Paratethys. This supports a hypothesis of possible connections during the latest Badenian between different areas of the Central Paratethys, as well as of the existence of a gateway between the Central Paratethys and the Mediterranean realm.
EN
The subject of the research was the Middle Miocene red algal limestone from the Włochy deposit, which is currently the only place of exploitation of the Pińczów Limestone representing a local type of the Leitha Limestone. The collected samples of this rock belong to the organodetric facies of diverse grain size and sorting of clastic material. Considering the proportions of characteristic skeleton remains, the composition of the coarse-grained organodetric facies is red algal-foraminiferalbryozoic, while of the fine-grained facies is foraminiferal-red algal. The cement of these rocks is predominantly sparite compared to micrite-clay matrix. A complement to petrographic studies was the chemical analysis and identification of mineral phases with X-ray diffraction. Moreover, physical and mechanical properties of samples were analyzed. Porosity of the rock was assessed in the polarizing and scanning microscope (SEM-EDS) observations, as well as with a porosimetric tests. The coarse-detrital limestone with a dominant binder in the form of intergranular cement is characterized by the apparent density sometimes exceeded 1.90 Mg/m3, while fine-grained limestone has the highest water absorbability (above 20%) and total porosity (about 40%). The above properties influenced high water absorption by capillarity, limiting the possibility of using limestone in places exposed to moisture. The observed relationship between the ultrasonic waves velocity and the uniaxial compressive strength gives the possibility of predicting the value of the latter parameter in the future. The limestones from Włochy deposit do not differ in quality from the previously used Pińczów Limestones, and their technical parameters predestine them for use as cladding material with insulating properties.
PL
Przedmiotem badań były środkowomioceńskie wapienie krasnorostowe ze złoża Włochy, jedynego obecnie miejsca eksploatacji wapieni pińczowskich, reprezentujących lokalny typ wapieni litawskich. Pobrane próbki tych skał reprezentują fację organodetrytyczną o zróżnicowanym uziarnieniu i wysortowaniu materiału okruchowego. Biorąc pod uwagę proporcje charakterystycznych szczątków szkieletowych, skład facji gruboziarnistej jest krasnorostowo-otwornicowo-mszywiołowy, zaś drobnoziarnistej – otwornicowo-krasnorostowy. Spoiwo tych skał stanowi cement sparytowy, przeważający nad matriks mikrytowo-ilastą. Uzupełnieniem obserwacji petrograficznych była analiza składu chemicznego i identyfikacja faz mineralnych przy pomocy dyfraktometrii rentgenowskiej (XRD). Ponadto wykonano badania właściwości fizycznych i mechanicznych. Porowatość skały oceniono na podstawie obserwacji w mikroskopie polaryzacyjnym i skaningowym (SEM-EDS) oraz w testach porozymetrycznych. Wapienie grubodetrytyczne z dominującym spoiwem w postaci cementu intergranularnego odznaczają się gęstością pozorną przekraczającą czasem 1,90 Mg/m3, podczas gdy drobnoziarniste mają najwyższą nasiąkliwość wagową (pow. 20%) i porowatość całkowitą (ok. 40%). Wpływa to na wysoką nasiąkliwość kapilarną, ograniczającą możliwości zastosowania wapienia w miejscach narażonych na zawilgocenia. Stwierdzona zależność pomiędzy prędkością fal ultradźwiękowych a wytrzymałością na ściskanie jednoosiowe daje możliwość prognozowania wartości tego ostatniego parametru w przyszłości. Wapienie ze złoża Włochy mają jakość podobną do innych wapieni pińczowskich eksploatowanych w przeszłości, a ich parametry techniczne predestynują je do zastosowania jako materiału okładzinowego o właściwościach izolacyjnych.
EN
The Miocene sedimentation history of the Brus denudation relict (the western part of the Carpathian Foredeep, Czech Republic) has been inferred from 20 m of silt/siltstones, sand/sandstones and limestones penetrated by the Brus-1 borehole. Detailed multiproxy lithofacies and biofacies analyses have allowed facies and palaeoenvironment interpretations. The presence of molluscs, brachiopods and fish fauna, as well as large benthic and epiphytic foraminifera indicates a generally shallow, subtropical, marine environment. Despite the scarcity of biostratigraphical markers, the section can be correlated with the lowermost Badenian (~15-16 Ma). In the siltstones in the lower part of the borehole, there are abundant low-salinity foraminifera, which may indicate increased rainfall. Linked to this is the nutrient enrichment of the sea bottom water inferred from the presence of the high-nutrient taxa accompanied by abundant calcareous nannoplankton eutrophic taxa such as Coccolithus pelagicus and eutrophic planktonic foraminifera of the Globigerina bulloides/praebulloides group. The main Planostegina bloom was recorded in a sandstone in the interval 12.5-7 m, and was not influenced by a shift from high-organic content Valvulineria assemblage of small foraminifera to an epiphytic one. The boundary between siliciclastic and carbonate sedimentation (-7.5 m) shows a drop in K and Th concentrations, and in the Th/U ratio, but a rise in the Th/K ratio. This change in radioactive element content may generally indicate a significant decrease in terrestrial sediment input which is further supported by the onset of limestone deposition. Reversal of the deposition regime and a decrease of clastic input into the basin may be related to the changing of the precipitation regime, probably triggered by orbitally-forced cyclicity.
EN
The paper deals with sub-evaporite Badenian deposits (Middle Miocene, Paratethys) that display a sudden appearance of globorotaliid taxa showing preferences in the taxonomic set and coiling direction. An interval of sinistrally coiled Jenkinsella mayeri with proportionally coiled Globoconella bykovae is at the bottom of the studied sequence. It is followed by an interval of proportionally coiled Jenkinsella transsylvanica. Proportionally coiled Globoconella bykovae with a small number of proportionally coiled Jenkinsella transsylvanica are at the top of the Moravian (CPN 7) substage (Orbulina suturalis alias Lagenidae Zone). The sub-evaporite part of the Wielician (CPN 8) substage (Uvigerina costai alias Spiroplectammina Zone) began with a globorotaliid-barren interval (IIC biozone). It is followed by biozone IID displaying three globorotallid peaks amongst globorotallid-barren deposits. Only globoconellas are present in all these three events. Proportionally coiled Globoconella bykovae appeared first. It is followed by proportionally coiled Globoconella minoritesta and sinistrally coiled Globoconella bykovae at the end of the biozone IID. Coiling preferences of globorotaliids have been compared to changes in the hydrographic regime unfolding during the CPN 7 and CPN 8 in the studied area of the Paratethys. The study discovers that the coiling of globorotaliids responded selectively to the hydrographic changes. Globoconella bykovae is highly opportunistic and can tolerate considerable temperature changes. Specimens of this taxon persist to coil proportionally during the sub-evaporite Badenian, except for the shift to sinistral coiling just prior to the Wielician evaporites. Sinistrally coiled Jenkinsella mayeri is the most sensitive to hydrographic changes. This taxon retreated at the onset of the temperature drop during the mid-Moravian cryptic cooling. This cooling is marked by the new jenkinsellid occurrence – proportionally coiled Jenkinsella transsylvanica. Proportionally coiled Globoconella minoritesta is present in the middle of the IID globorotaliid peaks. The globorotaliid coiling data, presented in this paper, has been calibrated to the global stratigraphy. The integrated data (foraminifera, nannofossils, oxygen and carbon stable isotopes, radiometric measurements) supports the view that the CPN 7/CPN 8 boundary is coeval to the Langhian/Serravalian one. In the Polish part of the Carpathian Foredeep, the boundary runs within the Skawina Formation.
EN
Zooxanthellate corals in the Badenian (Langhian to lower Serravallian) of western Ukraine occur in different lithofacies, but are most abundant in the upper Badenian coralgal reefs of the Ternopil Beds. The coral assemblage consists of five genera, with two predominant (Tarbellastraea and Porites) and three strongly subordinate (Favia, Heliastraea, Siderastrea). The present study is the first record of Heliastraea defrancei in the Fore-Carpathian Basin. The taxonomic composition of the corals indicates that their development occurred in conditions of some ecological stress, most probably connected with climate (location at the northern limit of coral distribution) and sedimentary environment (possible influx of terrigenous material). The coral assemblage shows similarities to numerous fossil reefs of Miocene age from the Paratethyan and Mediterranean realms.
EN
Dramatic tectonic and sea level changes of the Central Paratethys realm during the Middle Miocene resulted in changes of the coastal and seabed morphology affecting the composition of the marine association and the distribution of the facies along the coast. Three different episodes (marine-terrestrial-marine) in the environmental evolution are interpreted. A lower marine unit (Badenian; Lower Serravallian) reflects organodetrital sedimentation on and around an algal bioherm. Low terrigenous input maërl facies of typical rhodalgal carbonate factory type characterise the top of the algal mound. On the slopes, a rim of rhodechfor facies separated the bioherm from the rest of the bottom which had a seagrass cover. This high-energy rhodechfor carbonate factory is described from the Central Paratethys realm for the first time. It is composed mostly of coralline algae (Mesophyllum, Lithothamnion, Spongites and Lithophyllum), benthic foraminifers (Elphidium crispum, Neoconorbina terquemi, Miniacina sp., Borelis melo), echinoids (cidaroid, spatangoid and diadematoid groups) and bryozoans. Uplift of the Malé Karpaty Mts. resulted in tectonic activity in the vicinity, documented by the presence of clastic dikes and normal faults in the profile studied. Subsequent fluvial and terrestrial sedimentation is represented by regolith, palaeosoil and channel body deposits set discordantly on the top of lagoonal deposits. Finally, the third episode is represented by the Sarmatian transgressive marine sequence, which is characterized by coarse pebbly deposit eroded from an uplifted pre-Neogene basement. The strata studied originated in a warm temperate climate around the Badenian–Sarmatian transition.
EN
The genus Diodora Gray, 1821 is widely represented in the Middle Miocene of the Central Paratethys with specimens usually attributed to D. graeca (Linnaeus, 1758) or D. italic (Defrance, 1820), well-known recent species of the Atlantic / Mediterranean Basin. In samples from the Upper Badenian of Western Ukraine we found two clusters of Diodora specimens, showing a similarity with these species, but a review of shell diagnostic characters using a statistical approach has revealed their clear conchological separateness. The first species from Varovtsi and Horodok is attributed herein to D. nodosa (Eichwald, 1830), whereas the second species from Maksymivka is described as a new species, D. stalennuyi sp. nov. We consider that these molluscs inhabited the Polish-Ukrainian marginal part of the Late Badenian Basin. Detailed descriptions of the protoconch and teleoconch morphology of the taxa involved, including SEM images, are presented.
EN
Middle Miocene marine sediments in the Vienna and Danube Basins provide opportunities for analysis of spatial and temporal variations in the composition of molluscan communities and variations in species abundance and size. Varicorbula gibba (Olivi 1792) is an opportunistic bivalve with high tolerance to hypoxic conditions and variations in salinity (Holmes & Miller 2006) that appears in the Oligocene and persists to present, occurring in the tropical and northern temperate Eastern Atlantic and in the Mediterranean. Varicorbula belongs to one of the most frequent species in the benthic communities in the Paratethys during the Middle Miocene. However, spatial and temporal variations in taphonomic preservation and in abundance, size, and shape of this genus is poorly known – insights into such variations would improve paleoenvironmental interpretations. Molluscan assemblages with Varicorbula gibba (Olivi 1792) were collected from boreholes located in the western (Vienna basin) and eastern (Danube basin) margins of the Malé Karpaty Mountains (Slovakia). Boreholes intersect sediments of the Studienka Formation (Vienna Basin) respective Madunice Formation (Danube Basin) that belong mainly to the Upper Badenian stage (Janočko et al. 2003, Kováč et al. 2004). We have selected assemblages with more than 20 Varicorbula specimens from sediment samples sieved with 1 mm mesh size. A well preserved shelly material contains presently more than 130 specimens of Varicorbula , with ongoing screening of additional samples. We measured dimensions of four morphological variables (in mm). Shell length, shell height, posterior shell length and upper shell height were measured on all specimens. The valves were photographed and the dimensions were measured using ImageJ image analysis software. We used principal component analysis (PCA) and bivariate and multivariate allometric analyses to investigate ontogenetic and spatial variations in size and shape. We find that this taxon shows significant regional-scale differences in size distribution between the coeval Upper Badenian sediments in the Vienna and Danube basins, with significantly smaller size in the Danube Basin. In subtidal muds in the northern parts of the Vienna Basin, Varicorbula gibba achieves very high proportional community-level abundance and its median shell width ranges between 6–10 mm. Specimens from low-energy muddy sediments of the Vienna basin show low levels of taphonomic damage but are frequently bored by naticids snails that produce the trace fossil Oichnus paraboloides (Bromley 1981, Pek et al. 1997). In contrast, muddy sands from the northeastern margin of the Danube Basin; community composition is more even and median width ranges just between 3–4 mm. The higher sandy content and lower sedimentation rates (as evidenced by higher taphonomic damage, with higher proportion of bored specimens (by muricid snails – Oichnus simplex, in the Danube Basin; Bromley 1981) imply that the regional size differences can partly positively correlate with nutrient supply. Morphometric analyses indicate that height and width of individuals of this taxon undergo significant ontogenetic allometry and that smaller-sized individuals in the Danube Basin have a smaller width/ height ratio. Therefore, some shape differences in the height-width ratio between the two basins are unrelated to ontogenetic allometric effects (because height-width ratio changes even during the ontogeny).
EN
Studies of Miocene sediments in the Fore-Carpathian Basin, conducted by geologists from the University of Warsaw have provided new insights on the distribution of the facies infilling the basin, particularly in the forebulge and back-bulge zones. The origin of the large-scale sand bodies, evaporitic deposits and large-scale organic buildups is discussed, described and verified. These deposits originated in variable, shallow marine settings, differing in their water chemistry and the dynamics of sedimentary processes, and are unique with regard to the fossil assemblages they yield. Many years of taxonomic, biostratigraphic, palaeoecologic and ecotaphonomic investigations have resulted in the identification of the fossil assemblages of these sediments, their age, sedimentary settings and post-mortem conditions. Detailed studies were focused on corals, polychaetes, most classes of molluscs, crustaceans, echinoderms, and fishes.
EN
The Upper Badenian and Sarmatian sandstones recognized from boreholes in southeastern Poland and western Ukraine are very fine to medium-grained subarkosic and sublithic arenites and wackes. The deposits underwent diagenesis well below 100°C, and their evolutionary pathways of diagenetic and related reservoir properties represent eo- and mesodiagenesis. Eodiagenesis here comprised mechanical compaction, development of chlorite, microcrystalline calcite, pyrite, siderite, kaolinite and quartz, and dissolution of feldspar and mica grains. Mesodiagenesis included quartz and K-feldspar overgrowths, albitisation, crystallisation of dolomite and ankerite and coarsely crystalline calcite, dissolution of feldspar grains and carbonate cement, and illite growth. The isotopic data of δ18OVPDB of carbonate cements suggest their crystallisation from porewater which is a mixture of marine and meteoric waters. The δ13CVPDB values suggest derivation of carbon from microbial methanogenesis of organic matter. The 87Sr/86Sr values in coarsely crystalline calcite are higher than those of Badenian seawater. The radiogenic strontium may have been supplied during diagenesis by meteoric waters draining the continental area. The Middle Miocene sandstones show better filtration abilities (good and very good) in the western part of the study area (Poland) than in the east. Primary intergranular porosity is more frequent than secondary intragranular and intercrystalline porosities.The primary porosity was diminished due to compaction and cementation from west to east. Some increase in porosity was caused by dissolution of detrital grains and by decay of soft parts of organisms.
PL
Na podstawie wyników szczegółowej analizy zespołów nanoplanktonu wapiennego występującego w profilach badawczych otworów wiertniczych wykonanych w rejonie Buska, w północnej części zapadliska przedkarpackiego, określono pozycję stratygraficzną przewierconych sekwencji osadowych. W profilu otworu wiertniczego Busko (Młyny) PIG-1 iły margliste górnej części formacji skawińskiej zaliczono do poziomu nanoplanktonowego NN5 Sphenolithus heteromorphus odpowiadającego środkowemu badenowi Paratetydy i górnemu langowi/ dolnemu serrawalowi w prowincji medyterańskiej. Serie z ewaporatami (przeławicenia gipsów i iłów), wyróżnione jako formacja krzyżanowicka, oraz osady ilaste formacji z Machowa reprezentują poziom nanoplanktonowy NN6 Discoaster exilis. Przez analogię do innych basenów Paratetydy Środkowej granicę pięter badeńskiego i sarmackiego w profilu tego otworu wskazano bezpośrednio poniżej 20-metrowej miąższości sekwencji zawierającej skały bogate w okrzemki. W zespołach nanoplanktonu wapiennego dolny sarmat wyznacza pojawienie się gatunków Rhabdosphaera poculi Bóna et Kernerne i Rhabdosphaera procera Martini. W profilu otworu wiertniczego Kazimierza Wielka (Donosy) PIG-1, w osadach formacji z Machowa, wyróżniono poziom nanoplanktonowy NN6 Discoaster exilis. Masowy rozwój okrzemek udokumentowany w profilu otworu wiertniczego Busko (Młyny) PIG-1 świadczy o położeniu tego obszaru w pobliżu ujścia większej rzeki dostarczającej związki azotu, fosforu oraz krzemionkę. Zachowanie delikatnych frustul okrzemek było możliwe dzięki szybkiej sedymentacji osadów klastycznych w nadkładzie skał bogatych w okrzemki.
EN
The results of detailed analysis of calcareous nannoplankton in Miocene deposits from the northern part of the Carpathian Foredeep enabled stratigraphic conclusions. Marly clays of the uppermost part of the Skawina Formation in the Busko (Młyny) PIG-1 borehole section are correlated with the NN5 Sphenolithus heteromorphus Zone that corresponds with the Middle Badenian in the Paratethys and the upper Langhian/ Lower Serravalian in the Mediterranean region. The Krzyżanowice Formation, which includes evaporites (gypsum and clay intercalations), and the Machów Formation represent the NN6 Discoaster exilis Zone. By a comparison with other Paratethyan basins, the Badenian/ Sarmatian boundary is proposed just below a 20-metres thick set of diatomaceous siltstone layers. Among the calcareous nannofossil species, the appearance of Rhabdosphaera poculi Bóna et Kernerne and Rhabdosphaera procera Martini may point to the Lower Sarmatian transgression. Clayey sequences of the Machów Formation in the Kazimierza Wielka (Donosy) PIG-1 borehole correspond with the NN6 Discoaster exilis Zone. Abundance of diatom floras observed in the Busko (Młyny) PIG-1 borehole suggests a proximity of a river mouth that supplied water with nitrates, phosphates and silica. Preservation of delicate siliceous diatom frustules was possible due to rapid deposition of clastic sediments above diatomaceous siltstone.
EN
The most abundant benthic foraminifers recorded in the Wielician salt-enclosed xenoliths are: Bulimina spp., Uvigerina spp., Valvulineria complanata, and Cibicides pseudoungerianus. The predominant taxon in the planktonic assemblage is Globigerina bulloides with a median 98.9% in biozone IIC and 89.1% in the later IID. The IIC assemblage differs from the IID one in both taxon composi tion and abundance. The most pronounced differences are those revealed by Valvulineria complanata counts, number of benfhic taxa and the plankfonic/benthic (P/B) rafio. Pseudotriplasia minuta (one of the Wielician index taxa) occurs only in the IID biozone, present in 16 among 28 samples. There is a noticeable difference in sur- face sculpture morphology pattern in the predominant Bulimina and Uvigerina taxa in the IIC versus the IID biozones. There are smooth (Bulimina elongata) and weakly striate (Uvigerina semiornata plexus) forms in the IIC biozone, foll owed by heavily costate (Bulimina striata) and spinose-pustu l ate (Uvigerina orbignyana plexus) forms in the IID. Globigerina druryi and G. decoraperta- the CPN 8 planktonic index taxa - had not been found in the material studied. Globigerinita uvula is un- usually common in the samples studied. The samples analysed display an abundance of Globigerina bulloides typical of the sub-evaporite Wielician. Hence the studied Wielician stratotype area supports the thesis of the Globigerina bulloides Acme as the valid name designation for the substage.
PL
Celem opracowania jest rozpoziomowanie utworów miocenu środkowego w profilu Trojanowice 2 na podstawie zespołów nanoplanktonu wapiennego. W zespołach nanoplanktonu dominują gatunki długowieczne należące do Coccolithaceae i Prinsiaceae. Mniej licznie występują: Helicosphaeraceae, Sphenolithaceae i Discoasteraceae. Na podstawie oznaczonych w próbkach gatunków: Sphenolithus heteromorphus, S. abies, Helicosphaera walbersdorfensis, Discoaster exilis, Calcidiscus macintyrei, Cyclicargolithus floridanus, Reticulofenestra pseudoumbilica, Umbilicosphaera rotula oraz niewielkich rozmiarów form należących do rodzajów Reticulofenestra i Helicosphaera badane utwory odniesiono do poziomów kokolitowych NN5 i NN6 w standardowej zonacji Martiniego.
EN
The aim of the study was to establish the zonation of Middle Miocene sediments in the Trojanowice 2 borehole, based on calcareous nannoplankton investigations. Long-ranging families are dominant, representing Coccolithaceae (Coccolithus pelagicus) and Prinsiaceae (small reticulofenestrids, R. pseudoumbilica). Helicosphaeraceae (small helicosphaerids, H. kamptneri), Sphenolithaceae and Discoasteraceae, which are important for stratigraphic conclusions, occur less frequently. Based on the co-occurrence of Sphenolithus heteromorphus, S. abies, Helicosphaera walbersdorfensis, Discoaster exilis, Calcidiscus macintyrei, Cyclicargolithus floridanus, Reticulofenestra pseudoumbilica, Umbilicosphaera rotula and small forms belonging to the Reticulofenestra and Helicosphaera species, the sediments are included into NN5 and NN6 calcareous nannoplankton zones sensu Martini.
EN
The First Middle-Polish lignite seam of Middle Miocene age is exploited in all opencast mines in the Konin-Turek area, central Poland. This lignite seam contains a large number of xylites, for which the compaction coefficient was calculated as equal to 1.2. On the other hand, it is known that the compaction coefficient for the whole 1st Middle-Polish lignite seam is approximately 2.0. It follows that the compaction coefficient of xylites is 60% of the compaction coefficient for the whole lignite seam. Therefore, the compaction coefficient for the 1st Middle-Polish lignite seam can be easily determined on the basis of the compaction coefficient of xylites. In contrast to other methods, compaction studies of xylites are characterised by easy measurements and simple calculations, and allow neglecting, e.g., post-sedimentary deformation of the lignite seam.
EN
Globorotaliids of the Skawina Formation (Badenian) come from deposits representing CPN 7 (Orbulina suturalis Zone) and CPN 8 sub-evaporite Wielician (Globigerina druryi–G. decoraperta Zone alias Uvigerina costai Zone) age. There are two taxonomic groups of globorotaliids in the studied material: globoconellids (Globoconella bykovae and G. minoritesta) and jenkinsellids (Jenkinsella mayeri and J. transsylvanica). There are five stratigraphically-rank intervals of these foraminifers prior to the Middle Badenian salinity crisis in Central Paratethys. The investigated Badenian begins with G. bykovae–J. mayeri association followed by the first occurence (FO) of J. transsylvanica. The closing member of the CPN 7 biozone is the G. bykovae–J. transsylvanica assemblage. The jenkinsellids disappear during CPN 7: J. mayeri first and J. transsylvanica after. Since the base of CPN 8 in situ jenkinsellids have not been noted in the Badenian deposits. The CPN 8 begins with a stratigraphic interval barren of globorotaliids (biozone IIC in the Polish Paratethys). It is followed by episodic appearances of globoconellids (G. bykovae and G. minoritesta) in the sub-evaporite Wielician (IID biozone in Poland). G. minoritesta has been found in only one case so far. The globorotaliid stratigraphic units are distinct and well-correlated with changes in climate and the circulation of water masses in Paratethys. This study provides additional data on Mi3 in Paratethys. It documents a cryptic cooling event in the late Orbulina suturalis Zone (mid CPN 7) located at the late IIA–B assemblage (alias upper lagenide zone) in regional biostratigraphic scale. The event is recorded by J. transsylvanica Acme, matching with circa 1‰VPDB δ18O positive excursion. The event must have resulted in a considerable sea level drop – a trigger of the Moravian ecosystem demolition in the Paratethys environment.
EN
Foraminifers occurring in marls underlying the Middle Miocene Badenian gypsum in the northern Polish Carpathian Foredeep in one borehole section [Młyny (Busko) PIG 1] and in two dewatering pits in operating quarries (Leszcze and Borków) contain well-preserved foraminifers. Sixty-seven species of benthic and twenty-one species of planktonic foraminifers are recorded in the 12-m-thick section of the Młyny borehole. Benthic assemblages are characterized by the dominance of Bulimina and Uvigerina while planktonic assemblages are composed mainly by warm-water orbulinids and Globigerinoides spp. in the lower part of the Młyny section and by temperate-cold water Globigerina spp. in the upper part of the Młyny section as well as the Leszcze and Borków sections. The taxonomic composition of foraminiferal assemblages makes it possible to distinguish two foraminiferal zones in the Młyny borehole: the Orbulina suturalis and Uvigerina costai zones, and only the latter zone is accessible at Leszcze and Borków. The benthic foraminiferal successions in the studied interval suggest oxygenation and productivity changes in the Carpathian Foredeep Basin prior to the Badenian salinity crisis. Four intervals of lowered oxygenation and/or elevated organic flux to the sea-floor are recognized; the intervals in which foraminiferal assemblages suggest marine environments with lowered oxygenation in bottom waters alternate between the intervals where stress markers form less than 50% of the benthic foraminiferal assemblages. Benthic assemblages are moderately to highly diversified, and species have more equal frequencies. The upsection decrease in the proportion of planktonic foraminifers reflects the shallowing of the basin accompanied by a decrease in the temperature gradient between the upper (warmer) and deeper (colder) water beds. The average palaeotemperature of water based on d18O of Uvigerina and Globigerina decreased by ca. 2 and ca. 6°C, respectively (from 9.9 and 17.4°C in the Orbulina suturalis Zone to 7.9 and 11.5°C in the Uvigerina costai Zone, respectively). Below the gypsum, the d18O values of both benthic and planktonic foraminifers show quite large variations possibly due to the salinity increase. Coeval domination of benthic foraminiferal assemblages by Bulimina suggests increased surface water productivity and an increased organic flux to the sea-floor prior to the onset of evaporite deposition and/or salinity increase.
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While the marine molluscs from Sarmatian deposits of the Carpathian Foredeep Basin are known in general, there is a paucity of data on the terrestrial gastropods. Recently, a rich assemblage of terrestrial snails, accompanied by freshwater species, was found in Zwierzyniec, in the north-western, marginal part of the Carpathian Foredeep. Among the 38 taxa recognised, there are 22 species found in Poland for the first time; a new clausiliid species Triloba magurkai Stworzewicz sp. nov. is described. Freshwater gastropods (nine Lymnaeidae species and two Planorbidae species) were presented elsewhere. The malacofauna comprises aquatic and typical hygrophilous elements from coastal wetland habitats, some xerophilous species from dry, open environments, and gastropods from an adjacent subtropical woodland.
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Moundlike, globular to hemispherical bryozoan colonies of Celleporina medoborensis sp. nov. are documented from the calcareous organodetrital, slightly marly facies of the Lower Sarmatian (Volhynian) serpulid-microbialite reefs, in the Polupanivka and Ditkivtsi quarries (Medobory Hills), located at the northeastern margin of the Carpathian Foreland Basin (Central Paratethys) in western Ukraine. The colonies of C. medoborensis are multilamellar, often with a subcircular hole and occur together with numerous cyclostome bryozoans (crisiids, tubuliporinids, branching colonies of entalophoroids) as well as schizoporellid and cryptosulid cheilostomes, accompanied by a few macro- and micro-fossil taxa. The combination of morphological characters such as: thick radial ribs in the pseudoporous, variably-shaped area of the ovicell, and one or two small adventitious oral, as well as large vicarious avicularia are the main characteristic features of species. The rich occurrence of the celleporiform colonies of C. medoborensis sp. nov. within the fine-grained calcareous sands of Polupanivka and Ditkivtsi suggests a shallow-water setting and high availability of soft substrates, probably dominated by calcareous algae upon which the bryozoans may have settled in the Medobory reef biota during the Early Sarmatian.
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Sarmatian thin-bedded sandstone and shales have been a subject of statistical studies to differentiate between good and poor reservoir rocks and to show gas-saturated layers in comparison to water-saturated strata. Statistical studies including fractal analysis were performed on well logging data from the Sędziszów 34 borehole drilled in a belt of hydrocarbon deposits that continue below the northern edge of the Carpathian–Stebnik overthrust. Lithological variability and porosity differentiation and changes in water saturation were traced on the basis of the results of well logging interpretation. Basic statistics and histograms of petrophysical parameters have been analysed. A generalized second order fractal correlation dimension was calculated for all parameters and analysed as for a time series. Fractal dimensions did not correlated with the parameters, but good positive correlations between them and the parameters were observed and showed that the curves analysed had the same type of complexity. High correlation coefficients showed pairs of fractal dimensions for those parameters which had similar variability and the same curve roughness. The fractal correlation dimension described the type of complexity of the parameter (curve roughness) and indicated, for example, how shaliness influenced the reservoir properties of the local Middle Miocene. Therefore, the results were also useful in practice, which gave extra information on thin-bedded reservoir rocks.
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