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EN
Late Jurassic is the key epoch for an idea of the existence of the southeastern segment of the Mid-Polish Trough. New data on the evolution of Upper Jurassic deposits in the Carpathian Foredeep substrate provide information that there is a complete Oxfordian through Valanginian succession in the area of thick Oxfordian and Kimmeridgian deposits, proving the occurrence of the trough. Thickness of the Oxfordian and Kimmeridgian succession is twice to three times smaller than previously assumed. The facies development patterndistinguishes this area from the rest of the Late Jurassic basin. The sponge megafacies ranges up into the lower most Tithonian in this region.Tithonian Štramberk-type reefs occur near the Carpathian thrust front and alongside. The Late Jurassic and earliest Cretaceous facies are latitudinally arranged. Starting from the latest Middle Jurassic, the study area showed strong structural and facies relations to the Tethys do main. The collected data contradict the hypothesis that the Mid-Pol ish Trough continues in the Carpathian Foredeep substrate.
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%.
PL
Opracowanie paleontologiczne kolekcji amonitów oksfordu i dolnego kimerydu z wiercenia Kcynia IG IV z północnej Polski pozwoliło na zrewidowanie biostratygrafii występujących tu utworów i wydzielenie w całym profilu submedyterańskich poziomów i podpoziomów amonitowych. Oprócz obecnych w całym profilu amonitów submedyterańskich, ilościowe zestawienie przedstawicieli prowincji borealnej i subborealnej pozwoliło wykazać, że najsilniejsze wpływy tych prowincji rejestrują się w dolnej części poziomu Bimammatum i najwyższej części poziomu Hypselocyclum. Występowanie amonitów charakterystycznych dla różnych prowincji biogeograficznych w tych samych przedziałach profilu pozwoliło na wyróżnienie nowych powiązań korelacyjnych pomiędzy różnymi podziałami biostratygraficznymi: (1) dolna granica subborealnego poziomu Baylei, równoważna w podziale subborealnym dolnej granicy kimerydu, przebiega w obrębie wyższej części submedyterańskiego poziomu Bimammatum, (2) dolna granica subborealnego poziomu Mutabilis (sensu Birkelund i in., 1983) przebiega w obrębie najwyższej części submedyterańskiego poziomu Hypselocyclum. Analiza paleoekologiczna rozprzestrzenienia poszczególnych rodzin amonitów submedyterańskich w Polsce wskazuje, że w najwcześniejszym kimerydzie istniało bezpośrednie połączenie umożliwiające swobodne przemieszczanie amonitów pomiędzy północną Polska, a obszarami Jury Frankońskiej i Jury Szwabskiej poprzez obszary obecnie pozbawione osadów górnojurajskich.
EN
Palaeontological study of the ammonite collection of the Oxfordian and Lower Kimmeridgian in the Kcynia IG IV borehole in northern Poland has resulted in biostratigraphical revision of the succession and allowed the recognition of the Submediterranean Zones and Subzones. Although Submediterranean ammonites overdominate in the succession, Subboreal and Boreal ammonites increase proportionally in the lower Bimammatum Zone and the uppermost Hypselocyclum Zone reflecting significant ammonite invasions from the north. The co-occurrence of the ammonites indicative of different bioprovinces in the same intervals of the studied succession permits closer correlation of the zonal schemes. The new results of the correlation are as follows: (1) the lower boundary of the Baylei Zone of the Subboreal zonal scheme corresponding therein to the lower boundary of the Kimmeridgian lies within the upper part of the Submediterranean Bimammatum Zone, (2) the lower boundary of the Subboreal Mutabilis Zone (sensu Birkelund et al., 1983) lies within the uppermost part of the Submediterranean Hypselocyclum Zone. Palaeoecological analysis of the distribution of ammonites representing the particular Submediterranean families in Poland has shown that during the earliest Kimmeridgian there existed a direct marine connection between northern Poland and the Franconian and Swabian Albs enabling free migration of ammonites through the areas presently devoid of Upper Jurassic deposits.
EN
The Jurassic deposits which crop out in the quarries at Priborzhavske, Perechin and Novoselitsa in the Transcarpathian Ukraine comprise fairly similar successions, allowing their interpretation as corresponding to a single palaeogeographic zone in the Pieniny Klippen Basin. To the same zone belong also deposits from Beňatina quarry in eastern Slovakia. The following main stratigraphic units may be recognized: terrigenous and fleckenkalk-fleckenmergel deposits (Sinemurian-Pliensbachian), highly diversified and condensed deposits (uppermost Pliensbachian-Aalenian), crinoidal limestones (Bajocian, with a stratigraphical gap covering a lower part of the Lower Bajocian), nodular limestones of ammonitico-rosso type (uppermost Bajocian to Oxfordian with a possible gap covering the Callovian and Lower Oxfordian), well bedded micritic limestones (Kimmeridgian to Upper Tithonian), and bedded limestones with cherts of the maiolica type (from the uppermost Tithonian). Two rifting phases, well developed in the successions, took place: (1) Devín phase during latest Pliensbachian-Toarcian-and at least earliest Aalenian, and (2) Krasín phase during the Bajocian. The onset of pelagic deposits overlying the rift strata took place during the latest Bajocian, and corresponds well with the general subsidence and development of a more uniform facies pattern during the post-rifting time as everywhere in the Pieniny Klippen Basin. Selected ammonite taxa of the Lower and lower part of the Middle Jurassic are illustrated and discussed.
EN
The "black flysch" deposits (Szlachtowa Formation at Podubocze near Czorsztyn in Poland), attributed so far to the Pieniny Klippen Basin successions, and at Hałuszowa in Poland as well as at Kamienka in Eastern Slovakia, attributed to the Grajcarek Succession of the Magura Basin, have yielded rich dinoflagellate cyst assemblages consisting of forms both redeposited (from Upper Triassic to Aalenian) and indigenous (Lower Bajocian to Upper Bajocian). An Early to Late Bajocian age of the deposits investigated is thus indicated, and this along with other stratigraphical, sedimentological and tectonic data indicates that all the deposits in question represent the early stages of development of the Magura Basin. The formation of “black flysch” deposits was possibly related to the Early Bajocian uplift of the Czorsztyn Ridge which resulted from the opening of the Magura Ocean. The occurrence of the deposits of the Magura Basin below the overthrusted deposits of the Klippen Basin (Czorsztyn Unit) in the area of study results in a marked change in the structural interpretation of the Pieniny Klippen Belt.
EN
Detailed study of all the ammonite collections gathered by the authors in the Staffin Bay sections has resulted in minor changes in the distribution of ammonite taxa, and slight modification of the position of the Oxfordian/Kimmeridgian boundary. Most significant is the discovery of Pictonia (Triozites) cf. seminudata which results in the placing of the stage boundary 0.16 m below the level formerly proposed. This study discusses the evolution of the Subboreal family Aulacostephanidae, and the Boreal family Cardioceratidae, indicating changes in the patterns of individual development in the evolution of both families in terms of heterochrony. The Oxfordian/ Kimmeridgian boundary interval shows major morphological changes in both ammonite families which were released from phylogenetic constraints by heterochrony, closely related to changes in environmental conditions.
EN
Detailed study of ammonite and Dinoflagellata assemblages from the Bartoszyce IG 1 and Kcynia IG N cores in northern Poland comprises the stratigraphical interval at the Oxfordian/Kimmeridgian boundary. Correlations along well defined biostratigraphical horizons between the particular ammonite subdivisions typical of different biogeographical provinces and subdivisions based on Dinoflagellate cysts are discussed.
EN
The Czertezik Succession has been closely re-examined in its most classical sections of the Pieniny Klippen Belt (Western Carpathians) in Poland and eastern Slovakia. The study revealed the presence of the "lower nodular limestones" (Niedzica Limestone Formation), and resulted in discovery of Early Bajocian ammonite fauna in grey crinoidal limestones of the Smolegowa Limestone Formation/Flaki Limestone Formation, and the latest Bajocian to Early Bathonian ammonite fauna in the Niedzica Limestone Formation. These new data proved closer similarity between the Czertezik Succession and the Niedzica Succession than between the Czertezik Succession and the Czorsztyn Succession as it was suggested up to now. On the other hand, the Czertezik Succession represents deeper palaeogeographical position within the Pieniny Klippen Basin than the Niedzica Succession and it has been deposited near the Branisko/Kysuca Succession.
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.
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