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EN
The stratigraphical interval of the Kimmeridgian between the Bimammatum and the Hypselocylum zones in the SW margin of the Holy Cross Mts. shows a transition from the open shelf deep-neritic sponge megafacies to the shallow-water carbonate platform, including its development and decline. The uniform progradation of the shallow-water carbonate platform occurred at the end of the Planula Chron. Development of the shallow-water carbonate platform was controlled by climatic and tectonic factors. The former induced by orbital cyclicity resulted in changes of sea-level, revealed i.a. by the incoming of open-marine ammonite faunas, the latter were related to the synsedimentary activity of faults which resulted in contrasted facies changes. The episodically occurring strong influx of siliciclastic material was at least partly controlled by the tectonic activity. The newly elaborated formal lithostratigraphic subdivision takes into account the facies development of the succession in relation to climatically and tectonically induced changes. Such is e.g. the Małogoszcz Oolite Formation, corresponding to a single 100-kyr eccentricity cycle from the late Platynota Chron to the earliest Hypselocyclum Chron, bordered from the base and top by two transgressive climatically-controlled levels. The final stage of the shallow-water platform development at the end of the Hypselocyclum Chron was marked by the successive limitation of restricted environments, and the appearance of more open-marine conditions related to tectonic subsidence of the area of study. Comparison between the carbonate platform development of the Holy Cross Mts. in central Poland, and the coeval shallow-water carbonates of the Jura Mts. in northern Switzerland and south-eastern France provides an opportunity to consider similarities in the successions which can be attributed to the climatically-controlled sedimentary cyclicity and/or the wide-ranged tectonic phenomena. The palaeontological part of the study gives comments on the classification and phylogeny of ammonites of the families Ataxioceratidae and Aulacostephanidae.
EN
Vertebrate remains, mostly cryptodiran turtle shellfragments, pliosaur skull bones and teeth, plesiosaur vertebrae and crocodylomorph isolated teeth and skull fragments are described from the Upper Jurassic (Kimmeridgian) limestone beds of Krzyżanowice in the NE margin of the Holy Cross Mountains in Poland. The vertebrate fossils were collected during the palaeontological excavations conducted in 2018 and 2019 by the authors, and in the 1960s by a scientific team from the Museum of the Earth and the Institute of Paleobiology Polish Academy of Sciences. All osteological remains are generally very well preserved. This interesting vertebrate bones association from the upper part of the Kimmeridgian represents fossils of animals from two different types of environment. The first contains costal reptiles, like turtles and crocodylomorphs, the second one contains large pelagic animals - pliosaurids and plesiosaurids. This new vertebrate fauna from Poland has been correlated with age-equivalents from other regions of Europe and both Boreal/Subboreal and Mediterranean palaeobiogeographical realms.
EN
Oxygen and carbon isotope ratios of well-preserved calcitic bivalves from the Lower–lowermost Upper Kimmeridgian of Central Poland (SW margin of the Holy Cross Mountains) have been studied reconstruct palaeoenvironmental conditions and variations in ancient water chemistry. Low and scattered δ18O and δ13C values of bivalve shells from shallow carbonate deposits of the Hypselocyclum and the Hypselocyclum–Divisum zone boundary (-3.5 to -1.5, and 2.6 to 4.0‰, respectively) are a result of salinity changes, and local variations in the composition of dissolved inorganic carbon (DIC) in conditions of restricted water circulation. A slight increase in bivalve δ13C values and more densely clustering of δ18O values is observed after the marine transgression at the Divisum–Mutabilis zone boundary. A global decrease of δ13C values of marine carbonates is partly recorded in Lower–lowermost Upper Kimmeridgian bulk carbonates from central Poland (from the Radomsko Elevation and the Wieluń Upland). Local negative shifts and the data scatter are, however, observed in rocks deposited in a very shallow environment of carbonate platforms during the Platynota and Hypselocyclum chrons. This interval corresponds to the uppermost part of the lowstand systems track of a major regressive trend, which started already in the Late Oxfordian.
EN
New data are presented in relation to the worldwide definition of the Oxfordian/Kimmeridgian boundary, i.e. the base of the Kimmeridgian Stage. This data, mostly acquired in the past decade, supports the 2006 proposal to make the uniform boundary of the stages in the Flodigarry section at Staffin Bay on the Isle of Skye, northern Scotland. This boundary is based on the Subboreal-Boreal ammonite successions, and it is distinguished by the Pictonia flodigarriensis horizon at the base of the Subboreal Baylei Zone, and which corresponds precisely to the base of the Boreal Bauhini Zone. The boundary lies in the 0.16 m interval (1.24–1.08 m) below bed 36 in sections F6 at Flodigarry and it is thus proposed as the GSSP for the Oxfordian/ Kimmeridgian boundary. This boundary is recognized also by other stratigraphical data – palaeontological, geochemical and palaeomagnetic (including its well documented position close to the boundary between magnetozones F3n, and F3r which is placed in the 0.20 m interval – 1.28 m to 1.48 m below bed 36 – the latter corresponding to marine magnetic anomaly M26r). The boundary is clearly recognizable also in other sections of the Subboreal and Boreal areas discussed in the study, including southern England, Pomerania and the Peri-Baltic Syneclise, Russian Platform, Northern Central Siberia, Franz-Josef Land, Barents Sea and Norwegian Sea. It can be recognized also in the Submediterranean-Mediterranean areas of Europe and Asia where it correlates with the boundary between the Hypselum and the Bimmamatum ammonite zones. The changes in ammonite faunas at the boundary of these ammonite zones – mostly of ammonites of the families Aspidoceratidae and Oppeliidae – also enables the recognition of the boundary in the Tethyan and Indo-Pacific areas – such as the central part of the Americas (Cuba, Mexico), southern America, and southern parts of Asia. The climatic and environmental changes near to the Oxfordian/Kimmeridgian boundary discussed in the study relate mostly to the European areas. They show that very unstable environments at the end of the Oxfordian were subsequently replaced by more stable conditions representing a generally warming trend during the earliest Kimmeridgian. The definition of the boundary between the Oxfordian and Kimmeridgian as given in this study results in its wide correlation potential and means that it can be recognized in the different marine successions of the World.
EN
The Owadów-Brzezinki quarry is one of the most important paleontological sites in Poland, known from its exceptionally well-preserved Late Jurassic (Tithonian) fossils of marine and terrestrial biota, including horseshoe crabs and decapod crustaceans, rare ammonites, various insects and pterosaurs. This paper describes the discovery of new, well preserved reptile bones (ichthyosaurs, turtles and crocodylomorphs), which adds sigmficantly to our knowledge of these three gr°upü. The occurrence of large marine reptiles show open marine connections with the Sub- boreal-Boreal areas (both with Subboreal English seas and Boreal Arctic areas), and the Submediterranean Province (corresponding to the area of southern Germany).
EN
New biostratigraphical and carbon isotope data are presented for the Upper Jurassic limestones of the Raptawicka Turnia Limestone Formation (High Tatric unit, Western Tatra Mountains, Poland) from the Mały Giewont area. The Kimmeridgian, lower Tithonian and lower part of the upper Tithonian have been identified on the basis of calcareous dinocysts and calpionellids. Eight microfossil biozones are distinguished: acme Fibrata, acme Parvula, Moluccana, Borzai, Tithonica acme Pulla(?), Malmica, Chitinoidella and Crassicollaria (pars). The Kimmeridgian/Tithonian boundary is indicated at the top of the Borzai Zone 76 m above the base of the Raptawicka Turnia Limestone Formation. The microfossil stratigraphy suggests the late Early Kimmeridgian age (acme Parvula Zone) of the ammonites described by Passendorfer (1928). The taxon Taramelliceras ex gr. compsum found 14 m above those ammonites is Late Kimmeridgian in age. Seven microfacies types (MF) are identified in the Upper Jurassic limestones of the Mały Giewont area. The Bositra-Saccocomidae MF occurs across the Lower-Upper Kimmeridgian boundary. The planktonic and benthic foraminifera occur in the Upper Jurassic deposits of the Raptawicka Turnia Limestone Formation. The genera Lenticulina Lamarck and Spirillina Ehrenberg are common in the Kimmeridgian and Tithonian limestones. The palaeobathymetric evolution of the Kimmeridgian-Tithonian deposition recorded in the Mały Giewont sections reveals: the transgressive episode at the Lower/Upper Kimmeridgian boundary interval, the transgression peak during the Early Tithonian (Malmica Zone) and gradual shallowing of the High-Tatric swell in the Late Tithonian. Integrated isotope stratigraphy and biostratigraphy enabled correlation with the pelagic section of the Sub-Tatric succession in the Długa Valley section. The middle part of the Raptawicka Turnia Limestone Formation (Upper Kimmeridgian) might be correlated with the upper part of the Czajakowa Radiolarite Formation (red radiolarites) and Czorsztyn Formation in the Długa Valley section. The upper part of the Raptawicka Turnia Limestone Formation of Early Tithonian age corresponds mostly to the Jasenina Formation. The overall similarity of the δ13C decreasing values recorded in the Kimmeridgian–earliest Tithonian interval of the Mały Giewont (this study) and Długa Valley sections indicates that the generally shallow-water deposits of the Raptawicka Turnia Limestone Formation accumulated below the zone influenced by changes in the composition of marine water caused, for instance, by intense rainfalls.
PL
Z badań składu chemicznego i izotopowego wód górnojurajskiego poziomu wodonośnego rejonu Buska-Zdroju i Solca- Zdroju wynika, że są to solanki pierwotne i wody słone, zasilane w okresie przedplejstoceńskim, kiedy klimat charakteryzował się długimi okresami znacznie cieplejszymi niż współcześnie. Solanki te mają zdecydowanie cięższy skład izotopowy niż wody lecznicze, siarczkowe występujące na tym obszarze w utworach kredowych (głównie cenomanu) oraz zbliżone wartości wskaźników hydrochemicznych do wód morskich.
EN
The study of the chemical and isotopic composition of the Upper Jurassic aquifer in the Busko-Zdrój and Solec-Zdrój region suggests primary nature of the brines supplied before the Pleistocene under climate conditions characterized by long and much warmer periods than today. Compared to the sulphide healing waters occurring in the Cretaceous formations, mainly of Cenomanian age, the discussed brines and salt water are characterized by a far heavier isotopic composition as well as by the values of hydrochemical indica¬tors mostly similar to those of marine waters.
EN
The Buila-Vânturariţa Massif consists of massive Upper Jurassic reef limestones (Kimmeridgian–Tithonian) and Lower Cretaceous (Berriasian–Valanginian, and Barremian–?Lower Aptian) deposits. Besides corals and stromatoporoids, a wide range of micro-encrusters and microbialites has contributed to their development. In this study, the authors describe briefly and interpret the main facies associations and present the microfossil assemblages that are important for age determination. The distribution of facies associations, corroborated with the micropalaeontological content and early diagenetic features, indicate different depositional environments. The carbonate successions show the evolution of the Late Jurassic–Early Cretaceous depositional environments from slope and reef-front to internal-platform sedimentary settings, including peritidal environments in the lowermost Cretaceous. Early diagenesis, represented by synsedimentary cementation in the form of micritization (including cement crusts in the reef microframework), followed by dissolution, cementation and dolomitization in a meteoric regime, and void-filling late cementation during the burial stage.
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
Two partial skeletons of allosaurid theropods belonging to an adult and a juvenile from the Upper Jurassic (Tithonian) Morrison Formation of McElmo Canyon in Montezuma County, southwestern Colorado, were discovered in 1953 by the late Joseph T. Gregory and David Techter. The adult specimen consists of several isolated cranial and postcranial skeletal elements that are exceptionally well-preserved and include the left premaxilla, maxilla, dentary, teeth, quadratojugal, two caudal vertebrae, pubic peduncle, ischium, proximal tibia, a nearly complete left foot, and several isolated teeth, whereas the juvenile specimen is represented by the distal portion of the right dentary and a fragmentary splenial. The specimens represent a new species of Allosaurus, here named Allosaurus lucasi, which differs from Allosaurus fragilis by having a relatively short premaxilla and robust quadratojugal with short jugal process and a short quadrate process of the quadratojugal that is at the same level as the rostral quadratojugal ramus. The presence of a new species of Allosaurus in the Tithonian of North America provides further evidence of the taxonomic and morphological diversity of the Allosauridae clade and their continuous evolutionary success, which extended to the Cretaceous.
EN
In 1879, Othniel C. Marsh and Arthur Lakes collected in the Upper Jurassic Morrison Formation Quarry 12 at Como Bluff, Wyoming, USA, several isolated axial and appendicular skeletal elements of small theropod dinosaurs. Since the discovery the specimens remained unnoticed for over a century. The skeletal remains of small theropods are rare at Como Bluff and throughout the Morrison Formation. Their bones are delicately constructed, so they are not as well-preserved as the bones of large-bodied theropods. The bones of small theropods described here were found mixed with isolated crocodile teeth and turtle shells. Comparison of the skeletal materials with other known theropods from the Morrison Formation reveals that some of the bones belong to a very small juvenile Allosaurus fragilis and Torvosaurus tanneri and also to a new ceratosaur taxon, here named Fosterovenator churei, whereas the other bones represent previously unidentified juvenile taxa of basal tetanuran and coelurid theropods. The discovery and description of these fossil materials is significant because they provide important information about the Upper Jurassic terrestrial fauna of Quarry 12, Como Bluff, Wyoming. The presence of previously unidentified theropod taxa in the Morrison Formation indicates that the diversity of basal tetanuran and coelurid theropods may have been much greater than previously expected. Although the fossil material here described is largely fragmentary, it is tenable that theropods of different clades co-existed in the same ecosystems at the same time and most likely competed for the same food sources.
EN
The ammonite succession in the stratigraphical interval from the Bifurcatus Zone, through the Hypselum Zone, up to the lower part of the Bimammatum Zone corresponding to a large part of the Submediterranean Upper Oxfordian is studied in several sections of the Polish Jura in central Poland. The sections have yielded numerous ammonites of Submediterranean–Mediterranean affinity, but also, some of Boreal and Subboreal character. The co-occurrence of ammonites of different bioprovinces makes possible the correlation between the different zonal schemes – especially between the Subboreal/Boreal zonations and the Submediterranean/Mediterranean zonation. The correlation shows that the boundary of the Pseudocordata and Baylei zones (Subboreal) and its equivalent – the boundary of the Rosenkrantzi and Bauhini zones (Boreal), currently proposed as the primary standard of the Oxfordian-Kimmeridgian boundary within its GSSP at Staffin Bay (Isle of Skye, Scotland), runs in the Submediterranean/Mediterranean Upper Oxfordian near the base of the Bimammatum Zone. This discovery removes the main obstacle against the formal recognition of the Staffin Bay section as representing the uniform base of the Kimmeridgian Stage in the World and its GSSP. The ammonite taxa recognized are commented on and/or described, and suggestions on their taxonomical and phylogenetical relations are given in the palaeontological part of the study. A new taxon is established: Microbiplices anglicus vieluniensis subsp. nov.
EN
A development project of the Zalew Balaton area is being presently carried out. One of the project assumptions is to create a geological path across the object. However, detailed data about the geological structure of this place is not available. For this reason, the author has researched and updated the information about the rocks occurring in the walls of the old quarry. Primarily, terrain (textural and structural analysis, layers strike and dip measurements, geological boundaries delimitation) and laboratory analysis (X-Ray Powder Diffraction, microscopic rock samples analysis) were conducted. Collected data was afterwards compared with available literature. Within the steep slopes of excavation, strong-karsted, faulted Upper Jurassic (Oxfordian) carbonate sediments were revealed. These are massive, platy and crumpled limestone. These rocks could be deposited in changing conditions of sedimentation, when calm carbonate sedimentation was disturbed by underwater gravity flows, as demonstrated by their detrital character. One of the karst funnel on the northern slope was filled with Oligocene sand. As a result, groundwater fluctuations created a sarsen structure, popularly called the “Wielbłąd”. In relation to the planned geological path across the Zalew Balaton area, previous knowledge should be supplemented with new data, respectively processed and included on information panes, located within object. Plans of the path should pay attention to potential geotouristic safety, as well as to the geological values of the protected object, during its future modernization.
PL
Przedstawiono wyniki badań utworów jury górnej w dwóch peźnordzeniowych profilach wierceń, które opracowano przy realizacji „Zintegrowanego programu płytkich wierceń badawczych dla rozwiązania istotnych problemów budowy geologicznej Polski”. Utwory jury górnej reprezentują megafację gąbkową. Profil otworu wiertniczego Trojanowice 2 charakteryzuje biohermalny obszar facjalny w obrębie całej przewierconej części profilu oksfordu (od oksfordu dolnego do najniższej części poziomu Bimammatum oksfordu górnego). Profil Cianowice 2 charakteryzuje basenowy obszar facjalny (miedzybiohermalny basen Korzkwi) w obrębie niemal kompletnego stratygraficznie oksfordu. Znaczne różnice reliefu dna zbiornika wykazane na podstawie precyzyjnej biostratygrafii predysponowały do różnego rodzaju ruchów masowych. Utwory reprezentujące efekty takich ruchów rozpoznano w wyższej części profilu Cianowice 2. Stwierdzono, że zróżnicowanie na dwa wymienione powyżej obszary facjalne rozpoczęło się z początkiem późnego keloweju. Określono gęstość mumii gąbkowych w biohermie otworu wiertniczego Trojanowice 2. Zmieniała się ona od kilku do 63 mumii na metr bieżący profilu. W liczącym 201 m profilu doliczono się 2199 „generacji” gąbek krzemionkowych. Dla tego samego profilu wiercenia obliczono skrócenie profilu wapieni biohermalnych w wyniku procesu rozpuszczania pod ciśnieniem (stylolityzacji wzdłuż płaszczyzn poziomych). Minimalne skrócenie, obliczane jako amplituda stylolitu, wyniosło średnio 11,6%.
EN
We present the results of research in two Upper Jurassic drill core sections which were conducted with in the frames of “Integrated research program of shallow drillings to solve the major problems of geology of Poland”. The sections represent the Upper Jurassic sponge megafacies. The Trojanowice 2 drill core records the biohermal Oxfordian facies (from the Lower Oxfordian to the lowermost part of Bimammatum Zone of the Upper Oxfordian). The Cianowice 2 section is characterized by a facies typical of interbiohermal basins (Korzkiew Basin) and shows a nearly complete Oxfordian stratigraphic section. Significant differences of the sea bottom relief shown by the precise biostratigraphic method, evoked various types of mass movements. Rocks representing the effects of such movements have been recognized in the upper part of the Cianowice 2 drill core. The differences between the two regions mentioned above are evident from the beginning of the Late Callovian. We have determined the density of the sponge mummies in the Trojanowice 2 drill core. It varied from a few to 63 mummies per 1 metre of the section. In the 201-m long profile, a total of 2199 “generations” of siliceous sponges were found. In the same profile, we calculated the shortening of the limestone thickness as a result of pressure dissolution (along a horizontal plane). The minimal shortening, calculated as the stylolite amplitude, was averagely 11.6%.
EN
The paper presents a comparative analysis of a Lower Kimmeridgian layer with bored and encrusted hiatus concretions collected in three study areas, located in Central Poland. These studies demonstrate distinct similarities between the hiatus concretions in terms of their origin, development and stratigraphic position. The layer with its characteristic concretions seems to represent an important marker horizon for the Lower Kimmeridgian successions in Central Poland. The identification of this marker horizon in drill cores and exposures could be important for definition of the stratigraphic position of the sediments, which otherwise lack appropriate biostratigraphic information. The matrix of the concretions is composed of pelagic calciturbidites, which reflect flooding of the early Kimmeridgian platform. These sediments were lithified early and formed a hardground. The origin of the hiatus concretions probably is related to erosion of the hardground, followed by redeposition and several phases of exhumation and erosion, preceding final burial. The characteristic ecological successions, observed in the concretions, document an evolution from soft to firm and hard marine substrates, typical of hardgrounds and evidenced by various burrows, borings (Gastrochaenolites, Trypanites), and epizoans. Calciturbidite sedimentation, hardground erosion and redeposition of the hiatus concretions, known from deposits of the Platynota Zone in Central Poland, were associated with synsedimentary activity of the Holy Cross Fault, on the NE margin of the extensive, tectonic Małopolska Block.
EN
The non-cidaroid echinoids (subclass Euechinoidea Bronn, 1860) from the Oxfordian epicontinental sequence of Poland (Polish Jura, Holy Cross Mountains, Mid-Polish Anticlinorium) are assigned to the genera Hemipedina Wright, 1855, Hemicidaris L. Agassiz, 1838, Hemitiaris Pomel, 1883, Pseudocidaris Étallon, 1859, Stomechinus Desor, 1856, Eucosmus L. Agassiz in Agassiz and Desor, 1846, Glypticus L. Agassiz, 1840, Pleurodiadema de Loriol, 1870, Diplopodia McCoy, 1848, Trochotiara Lambert, 1901, Desorella Cotteau, 1855, and Heterocidaris Cotteau, 1860, plus one acropeltid taxon, and one taxon left in open nomenclature. Within the genus Hemicidaris L. Agassiz, 1838, the relationship between Hemicidaris intermedia (Fleming, 1828), Hemicidaris crenularis L. Agassiz, 1839 [non Lamarck, nec Goldfuss] and Hemicidaris quenstedti Mérian, 1855, all with confused taxonomy, is discussed. Based on test structure, the genera Polydiadema Lambert, 1883, and Trochotiara Lambert, 1901, of the family Emiratiidae Ali, 1990, are proved to be separate; the common species mamillana of F.A. Roemer (1836) is a typical Trochotiara. An attention is paid to the morphology of the tiny, juvenile specimens, common in Eucosmus decoratus L. Agassiz in L. Agassiz and Desor, 1846, and in Pleurodiadema stutzi (Moesch, 1867).
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.
PL
Chrom jest pierwiastkiem o szerokim zastosowaniu w przemyśle chemicznym i metalurgicznym, co stanowi główną przyczynę jego wprowadzania do środowiska w ściekach i wyciekach. Przykładem rejonu zanieczyszczonego związkami chromu są okolice Częstochowy. Szersze badania podjęto tu w latach 90. XX wieku z powodu zanieczyszczenia wód GZWP nr 326N, rozległego i zasobnego zbiornika szczelinowo-krasowego, występującego w utworach węglanowych jury górnej, stanowiącego główny poziom wodonośny oraz podstawę zaopatrzenia w wodę. Postawiono trzy koncepcje rozprzestrzeniania się zanieczyszczenia: (1) poziomy przepływ strumienia z dominacją procesów dyspersji, (2) głęboki poziomy przepływ strumienia z ascenzyjnym ruchem wód do współczesnego poziomu drenażu, (3) migracja zanieczyszczeń w wodach powierzchniowych. Wyniki opróbowania wód podziemnych przeprowadzonego w 2011 r. wykazały, że w porównaniu z 1995 r. zanieczyszczenie chromem uległo zmniejszeniu, jednak problem w dalszym ciągu istnieje, a kierunki i drogi migracji zanieczyszczeń w wodach poziomu górnojurajskiego nadal nie zostały jednoznacznie rozpoznane.
EN
Chromium is an element widely used in chemical and metallurgical industries that is the primary source of release of chromium compounds into the environment with industrial wastewater. An example of the region contaminated by chromium compounds is Częstochowa area. Wider research was undertaken in‘90s due to water pollution in the spacious and affluent fracture-karst reservoir MGWB No. 326N, associated with the Upper Jurassic carbonate formations. This MGWB is the main aquifer and a source of water for Częstochowa. The three hypotheses of chromium pollution pathways were formulated: (1) horizontal water flow with domination of dispersion processes, (2) deep horizontal flow with ascending movement of water to the contemporary drainage level, (3) migration of pollutants in surface water. Sampling of groundwater conducted in 2011 showed that compared to 1995, chromium pollution was reduced, although up to now the problem still exists and the directions and pathways of migration of contaminated Upper Jurassic groundwater have not been yet univocally identified.
EN
The Upper Jurassic carbonates exposed in the southern part of the Kraków-Częstochowa Upland are well known for their significant facies diversity related to the presence of microbial and microbial-sponge carbonate buildups and bedded detrital limestone in between. Both the buildups and detrital limestones revealed differential susceptibility to compaction which, apart from differential subsidence of the Palaeozoic basement and synsedimentary faulting, was one of the factors controlling seafloor palaeorelief in the Late Jurassic sedimentary basin. The compaction of the detrital limestones has been estimated with an experimental oedometric method in which specially prepared mixtures made of ground limestones from a quarry in the village of Żary were subjected to oedometer tests. The diameters of the detrital grains and their percentages in the limestones were determined by microscopic examinations of thin sections. The diameters were assigned to predetermined classes corresponding to the Udden-Wentworth scale. The rock samples were then ground down to the grain sizes observed in thin sections. From such materials, mixtures were prepared of grain size distributions corresponding to those observed in thin sections. After adding water the mixtures were subjected to oedometer tests. Analysis of the compression of such mixtures under specific loads enabled preparation of a mathematical formula suitable for the estimation of mechanical compaction of the limestone. The obtained values varied from 27.52 to 55.53% for a load corresponding to 300 metres burial depth. The most significant effect of mechanical compaction was observed for loads representing only 2 metres burial depth. Further loading resulted in a much smaller reduction in sample height. The results of the oedometer tests cannot be used directly to determine compaction of the detrital limestones. Mainly because microscopic observations of thin sections of the experimental material show that chemical compaction was also an important factor influencing thickness reduction of the limestones.
EN
The Upper Jurassic strata of the Krížna Unit in the Tatra Mts. comprises pelagic, fine-grained and well-oxygenated deposits. They are represented by red radiolarites and radiolarian limestones (Czajakowa Radiolarites Formation), red nodular limestones (Czorsztyn Limestones Formation) and wavy, platy or nodular light grey and reddish limestones and marlstones (Jasenina Formation). These deposits are mainly wackestones characterized by a succession of the following microfacies: radiolarian, filament-Saccocoma, Saccocoma and Globochaete–Saccocoma. The section comprises four calcareous dinoflagellate zones, i.e. the Late Kimmeridgian Moluccana Zone, and the Early Tithonian Borzai, Pulla and Malmica zones. In the uppermost part of the studied section, the Early Tithonian Dobeni Subzone of the Chitinoidella Zone has been identified. Using these biostratigraphic data, the sedimentation rate for the Late Kimmeridgian (Borzai Zone) and Early Tithonian (Dobeni Subzone of the Chitinoidella Zone) interval is estimated as 3.7 m/my. This is in accordance with the general trend of increasing sedimentation rate through the Tithonian and Berriasian. The increased supply of clastic material in the Jasenina Formation may have been caused by climate changes and continental weathering. The sedimentation was controlled mainly by eustatic changes and fluctuations in ACD and CCD levels.
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