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EN
The formation of the Polish part of the Outer Carpathian Basin was initiated by the rifting process which led to the collapse and disintegration of the southern margins of the European Platform in the Late Jurassic. Fragments of carbonate platform were incorporated into the basin structures which divided the area into several sedimentary zones located at different depth. Under these conditions, most of the carbonate sediments were transported to the basin in the form of submarine landslides and gravity flows of varying densities, or accumulated during pelagic sedimentation. These deposits belong to two formations exposed in the westernmost part of the Polish Outer Carpathians, located near the Polish-Czech border. The first is mainly represented by the Tithonian marls (Vendryne Fm.) which also contain redeposited carbonate rocks and fossils (Oxfordian-Tithonian), the second is composed of limestones and marly shales of the late Tithonian-Berriasian (Cieszyn Limestone Fm.). These oldest sedimentary rocks in the Polish Outer Carpathians contain mainly benthic foraminifers and very scarce plankton occurring in exotic blocks and sometimes directly in sediments forming both formations. The first group includes forms with calcareous walls and also cemented with siliceous or calcareous material. Calcareous benthic forms belong mainly to Vagulinidae (Vaginulina, Vaginulinopsis, Astacolus, Citharina, Citharinella, Lenticulina, Palmula), Nodosariae (i.e. Frondicularia, Nodosaria, Dentalina), Epistominidae (Epistomina), and Polymorphinidae (Guttulina), while agglutinated taxa are represented by Verneulinidae (Uvigerinammina, Paleogaudryina, Belorussiella, Verneuilina), Andercotrymidae (Praedorothia, Protomarssonella, Pseudomarssonella) and Textulariopsidae (Bicazammina, Hagimashella, Textulariopsis). They can be related to the Jurassic shelf microfauna, which are known both from the Tethys and the European Platform. Among foraminiferal benthos there are also very rare aggluinated taxa belonging to several genera: Melathrokerion, Buccicrenata, Alveosepta, Pseudocyclammina, and the more common calcareous forms of Andersenolina, Neotrocholina, Trocholina, Paalzowella, as well as of Discorbis, which inhabited shallow marine environments formed around the elevations within the basin as well as on its coast. Recently, apart from the benthic microfauna isolated Globigerina-like forms have been also found in the Tithonian deposits. These few forms resemble early planktonic foraminifera of the Western Tethys (Gl. oxfordiana, F. hoterivica) as well as the taxa known epicontinental and subTethyan seas located north (“Gl.” stellapolaris) and east (Gl. balakhmatovae, G. terquemi) of the studied area. The taxonomy, abundance and state of preservation of the described foraminifera from the early basin of the Polish Outer Carpathians indicate a connection with the gradually degraded areas of the platform inhabited by benthic and plankton communities from both the Tethyan and Boreal seas. The studied foraminifera resemble the microfauna of Western and Eastern Tethys and adjacent platforms.
EN
The Coniacian-Santonian series in the Aures Mountains of northeastern Algeria is characterized by marly-dominated sedimentation processes. This study aims to comprehensively investigate this series by combining lithostratigraphic and biostratigraphic data. The unique paleogeographic position of the Aures basin supports the co-occurrence of diverse paleontological contents in the Upper Cretaceous sediments. The methodology employed in this study includes a detailed bio-lithostratigraphic analysis to subdivide the Coniacian-Santonian series into two distinct sets. The first set comprises alternating marl-limestone units that exhibit a high fossil concentration from the Coniacian age, while the second set mainly consists of marly sediments corresponding to the Santonian age. The results obtained from this study highlight the geographical distribution of litho-biostratigraphic characteristics and reveal the presence of two formations. The lower formation is characterized by carbonated marls intercalated with limestone banks, containing fossils of Peroniceras (Tissotia tissoto) from the Coniacian age. Meanwhile, the upper formation is predominantly marly and indicates the Santonian age by displaying fossils of Palcenticeras polypsis. Furthermore, a biostratigraphic analysis focused on foraminifers allows for the subdivision of the Coniacian-Santonian series in the Aures Mountains into three distinct biozones. The first biozone corresponds to the lower Coniacian age and is identified by the presence of Dicarinella primitiva. The second biozone represents the middle to upper coniacian age and contains Dicarinella concavata fossils. Finally, the third biozone, belonging to the Santonian age, is marked by the occurrence of Dicarinella asymetrica. The boundary between the Coniacian and Santonian series in the Aures Mountains is characterized by the first appearance of Dicarinella asymetrica and Palcenticeras polypsis species. This multidisciplinary study provides valuable insights into the litho-biostratigraphic characteristics and geographical distribution of the Coniacian-Santonian series in the Aures Mountains. The findings make a significant contribution to a better understanding of sedimentary processes and the paleontological content within this region during the Upper Cretaceous period.
EN
Upper Turonian to lower Coniacian marls of the Strehlen Formation of the Graupa 60/1 core were investigated for their foraminiferal content to add stratigraphical and palaeoenvironmental information about the transitional facies zone of the Saxonian Cretaceous Basin. Further comparison with foraminiferal faunas of the Brausnitzbach Marl (Schrammstein Formation) were carried out to clarify its relationship to the marls of the Graupa 60/1 core. Tethyan agglutinated marker species for the late Turonian to early Coniacian confirm the proposed age of the marls of the Graupa 60/1 core and the Brausnitzbach Marl. The palaeoenvironment of the marls reflects middle to outer shelf conditions. The maximum flooding zones of genetic sequences TUR6, TUR7 and CON1 could be linked to acmes of foraminiferal species and foraminiferal morphogroups. In general, a rise of the relative sea-level can be recognised from the base to the top of the marls of the Graupa 60/1 core. While agglutinated foraminiferal assemblages suggest a generally high organic matter influx and variable but high productivity in the Graupa 60/1 core, the Brausnitzbach Marl deposition was characterized by moderate productivity and a generally shallower water depth.
EN
The Campanian-Paleocene Jaworzynka Formation, a part of the Magura Nappe succession in the Polish Outer Carpathians, is described in terms of its detailed litho- and biostratigraphy. The formation stretches along the marginal part of the Siary Unit, from the Jaworzynka stratotype area in the Silesian Beskid Mts up to the Mszana Dolna area in the Beskid Wyspowy Mts. Its equivalent in the Moravskoslezské Beskydy Mts of the Czech Republic is the Soláň Formation. In the stratotype area, the formation displays complex structure. We distinguish four lithological units, i.e., Biotite Sandstone and Shale (I), Shale (II), Mutne Sandstone Member (III) and Thin-bedded Turbidite (IV) and provide the first detailed biostratigraphy of particular units. The first unit forms the most prominent part of the formation. It was deposited in the Middle Campanian-earliest Maastrichtian within the upper part of Caudammina gigantea Zone up to the lower part of the Rzehakina inclusa Zone. The second unit occurs only locally and its age is limited to the Maastrichtian, to the Rzehakina inclusa Zone. The third unit is composed of thick-bedded sandstones that in some parts may form more than the half of the total thickness of the formation. It is Late Maastrichtian-Danian in age and is placed in the upper part of the Rzehakina inclusa Zone and the lower part of the Rzehakina fissistomata Zone. It is usually covered by a thin package of thin-bedded turbiditic sandstone and shales of Danian-Thanetian age with foraminifera of the Rzehakina fissistomata Zone.
EN
Micropalaeontological Laboratory at the Polish Geological Institute in Warsaw was organized by Władysław Pożaryski in 1947. The studies were going towards the development of regional micropalaeontological stratigraphic schemes of Mesozoic deposits of Poland (excluding the Carpathians) and dating rocks, based on micropalaeontological analyses. Results of examination of a huge number of samples (over 90,000) have been the basis for biostratigraphical reports and monographs, diagnoses of many new taxa, and over 1000 archival collections of Mesozoic, Paleogene and Neogene microfaunas. The golden era of the Laboratory had lasted almost four decades.
EN
The present paper discusses foraminiferal assemblages and biozones established on the basis of studies of samples from ten borehole sequences of the Khanty-Mansiysk Horizon in the Samotlor area of the northern palaeobiogeographical district of western Siberia (Russia). In this region, middle and late Albian foraminiferal assemblages were first distinguished in western Siberia. Levels from which these assemblages have been recovered, are here referred to the following foraminiferal zones, the Ammobaculites fragmentarius–Gaudryinopsis filiformis Zone (middle Albian) and the Ammotium braunsteini–Verneuilinoides borealis assanoviensis Zone (upper Albian). Zonal assemblages are dominated by representatives of the orders Ammodiscida, Textulariida and Ataxophragmiida. Species of the ataxophragmiid genera Verneuilinoides, Pseudoverneuilina and Gaudryinopsis are the most characteristic, inclusive of several key index forms. Foraminiferal tests consist of agglutinated quartz-silica, the wall microstructure being almost exclusively medium and coarse grained. In specific composition, the Albian assemblages from the Samotlor area are similar to those from Transuralia (Russia) and to the Canadian Province, which, together with West-Siberian Province, forms the Arctic palaeobiogeographical realm.
PL
Skład i zmiany zespołów otwornic pochodzących z najwyższej części utworów podewaporatowych w otworze wiertniczym Busko (Młyny) PIG-1 (głęb. 188–192 m), zlokalizowanym w północnej części zbiornika przedkarpackiego (Paratetyda Środkowa), wskazują, że zbiornik, w którym powstawały osady margliste, był słabo wentylowany, z dużym deficytem tlenowym w wodach przydennych oraz ze środowiskiem eutroficznym w wodach powierzchniowych. Zbiornik ten, o głębokości 50–70 m, wypełniały wody chłodne o zasoleniu typowym dla zbiornika morskiego. Obserwowane w najwyższej części profilu prawie całkowite wyeliminowanie otwornic Uvigerina i zajęcie na krótko zwolnionej niszy przez Fursenkoina acuta (zespół D4c) oraz zdominowanie składu najmłodszego zespołu (D4d) przez tolerującą podwyższone zasolenie Bulimina elongata może jednak wskazywać na znaczne podwyższenie zasolenia w trakcie depozycji najwyższej części utworów poprzedzających depozycję gipsów. Profil gipsów badeńskich w badanym otworze wiertniczym w porównaniu z bardziej brzeżną strefą platformy gipsowej cechuje się redukcją dolnej, autochtonicznej części gipsów oraz specyficznym wykształceniem najniższej jednostki gipsów. W matriksie ilastym występują tam gruzły gipsu bardzo przypominające małe, chaotycznie ułożone blokowe zrosty krystaliczne, określane jako facja szkieletowa gipsów szklicowych, związana w niecce Nidy oraz na Morawach z obniżeniami dna. Wykształcenie profilu gipsów wskazuje na głębsze środowisko sedymentacji niż to stwierdzono w rejonie niecki Nidy.
EN
Composition and changes in foraminiferal assemblages recorded in the uppermost part of the sub-evaporite deposits of the Busko (Młyny) PIG-1 borehole (depth 188–192 m) in the northernmost part of the Fore-Carpathian Basin (Central Paratethys) indicate that the basin, in which marly deposits have originated, was poorly ventilated with a great oxygen deficit in the bottom waters, and was characterised by mainly eutrophic conditions in surface waters. The basin was 50–70 m deep. The waters were cool and of normal seawater salinity, although the recorded (in the uppermost part of the section) almost complete disappearance of Uvigerina foraminifers, occupation (for a short time) of the vacant niche by Fursenkoina acuta (assemblage D4c), and the dominance of Bulimina elongata (tolerant to increased salinity) in the youngest assemblage (D4d) may indicate a considerable increase of seawater salinity during the deposition of the uppermost part of the sub-evaporite strata. The gypsum section is characterised, when compared to the more marginal gypsum sections of the Nida Trough, by a reduction of the lower, autochthonous part of the gypsum section and a specific development of the lowermost gypsum unit. It contains gypsum nodules resembling small, chaotically arranged gypsum intergrowths in the clayey matrix. Such facies is regarded as the skeletal facies of the giant gypsum intergrowth facies of the Nida Trough and Moravia, and is related to depositional lows at the beginning of the gypsum deposition. The gypsum sequence in this borehole indicates a deeper sedimentary environment than inferred for the Nida Trough.
PL
Badania mikropaleontologiczne przeprowadzono na próbkach pobranych z kompleksu osadów mioceńskich przewierconych otworami wiertniczymi Busko (Młyny) PIG-1 i Kazimierza Wielka (Donosy) PIG-1. Oba otwory są zlokalizowane w północno-zachodniej części zapadliska przedkarpackiego. Materiał do badań pobrano z ilastych i ilasto-marglistych przewarstwień występujących w osadach pod- ścielających serię ewaporatów, z serii ewaporatów oraz z jej nadkładu. W artykule przedstawiono wyniki taksonomicznej i biostratygraficznej analizy wyróżnionych zespołów otwornicowych. Obecność w tych zespołach taksonów wskaźnikowych dla określonych poziomów otwornicowych umożliwiła ich korelację z regionalnymi jednostkami biostratygraficznymi ustanowionymi dla różnych obszarów zapadliska przedkarpackiego. W profilu otworu wiertniczego Busko (Młyny) PIG-1 wyodrębniono pięć zespołów mikrofaunistycznych (Z.b.I– Z.s.V). Cztery z nich skorelowano z badeńskimi poziomami otwornicowymi: z poziomem Orbulina suturalis/ Praeorbulina (Z.b.I) datowanym na wczesny baden (moraw) oraz z poziomami Neobulimina longa (Z.b.II), Velapertina indigena (Z.b.III) i Hanzawaia crassiseptata (Z.b.IV) datowanymi na poźny baden (kosow). Ostatni zespół przyporządkowano poziomowi Anomalinoides dividens (Z.s.V) z wczesnego sarmatu (wołyn). W profilu otworu wiertniczego Kazimierza Wielka (Donosy) PIG-1 wydzielono trzy zespoły otwornicowe (Z.b.I–Z.s.III). Najstarszy zespół odpowiada poziomowi otwornicowemu Velapertina indigena (Z.b.I) datowanemu na późny baden (kosow), a następny poziomowi Varidentella sarmatica (Z.s.II) z wczesnego sarmatu (wołyn). Trzeci zespół (Z.s.III), ze względu na zły stan zachowania mikrofauny, zaliczono ogólnie do sarmatu. Zastępujące się obocznie planktoniczne i bentoniczne zespoły otwornicowe potwierdzają duże zróżnicowanie facjalne osadów, które powstały w późnym badenie i we wczesnym sarmacie w brzeżnej części zapadliska przedkarpackiego.
EN
Micropaleontological study of Miocene deposits from the Busko (Młyny) PIG-1 and Kazimierza Wielka (Donosy) PIG-1 boreholes, located in the northern part of the Carpathian Foredeep, has allowed taxonomic and biostratigraphic characteristics of foraminiferal assemblages. The samples were taken from clay and clay-marly interbeds in sub-evaporitic, evaporitic and supra-evaporitc complexes. In the Busko (Młyny) PIG-1 borehole, five foraminiferal assemblages have been defined (Z.b.I–Z.s.V), corresponding with the following foraminiferal zones: Orbulina suturalis/ Praeorbulina – Z.b.I (Moravian substage of the Early Badenian), Neobulimina longa – Z.b.II; Velapertina indigena – Z.b.III, Hanzawaia crassiseptata – Z.b.IV (Kosovian substage of the Late Badenian) and Anomalinoides dividens – Z.b.V (Volhynian substage of the Early Sarmatian). In the Kazimierza Wielka (Donosy) PIG-1 borehole, two foraminiferal assemblages have been identified (Z.b.I and Z.s.II), correlated with following foraminiferal zones Velapertina indigena – Z.b.I (Kosovian substage of the Late Badenian) and Varidentella sarmatica – Z.s.II (Volhynian substage of the Early Sarmatian). The third assemblage (Z.s.III), because of poor preservation of foraminifers has been attributed to the Sarmatian stage in general. Lateral replacement of planktonic and benthonic foraminiferal assemblages confirms a significant facies variability of the Late Badenian deposits that accumulated in the northern margin of marine basin in the Carpathian Foredeep.
9
Content available The Permian and Triassic in the Albanian Alps
EN
The sedimentary succession of the Permian to Middle Triassic of the Albanian Alps is described, as part of the eastern Adria passive margin towards the Tethys. A carbonate ramp deepening towards NE in present day coordinates developed during the Middle Permian and was affected by block faulting with the deposition of carbonate breccia. The Early Triassic was characterized by intense terrigenous deposition with several cobble conglomerate units up to 80 m-thick, and by oolitic carbonate shoals. The fine clastic deposition ended gradually during the earliest Anisian and a wide calcarenitic ramp occupied the area, with small local carbonate mounds. Basinward, the red nodular limestone of the Han Bulog Formation was interbedded with calcarenitic material exported from the ramp. Drowning to more open conditions occurred towards the end of the Pelsonian. Subsequently, cherty limestone and tuffitic layers spread over the entire area. Towards the end of the Ladinian, with the end of the volcanic activity, red pelagic limestone was deposited locally for a short period. By the latest Ladinian most of the area returned to shallow-water conditions, with a peritidal carbonate platform. In the Theth area, in contrast, a basin with black organic-rich dolostone and limestone developed which seems to be unique in that part of the Adria passive margin. The occurrence of cobble conglomerate units in the Lower Triassic testifies to very active block faulting and high accommodation, not yet described for the area.
EN
Latest Eocene plant macrofossils and trace fossils collected a century ago by Wiktor Kuźniar are revised and their stratigraphical and palaeoecological meaning is re-considered. They derive from marine limestones and marls cropping out on the northern slope of the Hruby Regiel mountain in the Western Tatra Mountains. Leaves belonging to the families Fagaceae and Lauraceae and fruits of the palm Nypa are recognized. The co-occurrence of the planktonic foraminifer taxa Chiloguembelina cf. gracillima and Globigerinatheca cf. index and fruits of Nypa suggests a latest Eocene age of the fossil flora. The plant assemblage is typical of paratropical or subtropical evergreen forests in a warm and humid subtropical climate, recent counterparts of which occur in southeast Asia. The presence of Nypa is characteristic of mangroves. The good state of preservation of the leaves suggests coastline proximity during sedimentation of the plant-bearing deposits.
EN
The Berriasian deposits of the central Crimea have been studied in order to compose a composite sequence of the stage with detailed palaeontological characterization. The Berriasian includes the Bedenekyrskaya Formation (packstones), Bechku Formation (siltstones, sandstones) and Kuchkinskaya Formation (sponge packstones, clays, siltstones, and coral-algal bioherm framestones). The Jacobi, Occitanica and Boissieri zones were identified based on ammonites found in the sections. A micropalaeontological analysis determined the following: 6 foraminiferal assemblages, the Costacythere khiamii – Hechticythere belbekensis and Costacythere drushchitzi – Reticythere marfenini ostracod assemblages, and a Phoberocysta neocomica dinocyst assemblage. Palaeoecological analysis of the ostracod and foraminiferal associations indicates a moderately warm marine basin with normal salinity and shallow depths (tens of meters). Only the sponge horizon was probably deposited in a deeper-water environment.
EN
The study of 114 core samples from seven borehole sections of the Van-Eganskaya area in the central part of Western Siberia yielded sufficient data to investigate the Late Cenomanian-Turonian foraminifers, palaeoenvironments, and the Late Cenomanian-Turonian biostratigraphy of this poorly studied area. Two Late Cenomanian foraminifer zones were established, viz. a (lower) Saccammina micra - Ammomarginulina sibirica Zone and an (upper) Trochammina wetteri tumida - Verneuilinoides kansasensis Zone. They reflect changes in the species composition of the foraminifer assemblages and lithology of the host rocks of the Uvatskian Horizon. In the lower part of the upper zone, beds with Gaudryinopsis nanushukensis elongatus are present. The changes in the species composition and lithology of the upper Cenomanian resulted from water-depth variations during the Boreal transgression. Two distinct assemblages and two homonymous zones, viz. the (lower) Gaudryinopsis angustus and the (upper) Pseudoclavulina hastata zones occur in the Turonian clayey cap-rocks of the superimposed Kuznetsovskian Horizon. Comparison of the Late Cenomanian-Turonian assemblages from the West-Siberian and Canadian provinces of the same Arctic palaeobiogeographical realm shows that the West-Siberian species are the same as, and closely related to, Canadian taxa, along with geographical subspecies. This comparison allows a detailed correlation, which results in a precise dating of the foraminifer zones.
EN
The Turonian and Coniacian (Upper Cretaceous) of the Mangyshlak Mts., western Kazakhstan, yielded a rich and relatively complete inoceramid bivalve record. The faunas and their succession correspond to those known from central and eastern Europe, allowing the zonation established in the latter areas to be applied in a virtually identical form. The gaps in the record of the group in Mangyshlak stem from the regional hiatuses in the geological record in the area and do not reflect any biogeographical differences between eastern and central-western Europe. Planktonic foraminifera are rare. Four successive interval range zones can be distinguished: in ascending stratigraphic order, the Helvetoglobotrunaca helvetica, Marginotruncaca pseudolinneiana, Marginotruncana coronata, and Concavotruncana concavata zones. Their correlation with the inoceramid zonation and, consequently, with the chronostratigraphic scheme, is demonstrated. The zonation and chronostratigraphic subdivision as applied in Mangyshlak may easily be applied to other areas of the peri-Caspian region (Caucasus, Tuarkyr, Kopet-Dagh, SE margin of the East-European Craton).
EN
The foraminiferal and radiolarian biostratigraphy of selected sections of the Zabijak Formation, the youngest sediments of the Tatra massif (Central Western Carpathians), have been studied. Benthic foraminifers, mainly agglutinated species, occur abundantly and continuously throughout the studied succession, while planktic foraminifers are generally sparse. Five planktic and two benthic foraminiferal zones have been recognized. The marly part of the Zabijak Formation comprises the Pseudothalmanninella ticinensis (Upper Albian) through the Rotalipora cushmani (Upper Cenomanian) planktic foraminiferal zones, and the Haplophragmoides nonioninoides and Bulbobaculites problematicus benthic foraminiferal zones. The radiolarians were recognized exclusively in the Lower Cenomanian part of the formation.
EN
The Middle Miocene (Upper Badenian) coralline algal reefs of Western Ukraine contain caverns (up to 1 m across) and fissures that are filled by Sarmatian deposits: marly clays, clayey carbonate sand and bioclastic, bryozoan-rich sand. These deposits often contain abundant and very well preserved calcareous benthic foraminifera; agglutinated forms have not been recorded. Foraminiferal tests quite commonly show morphological abnormalities, e.g. twin forms or tests with irregularities in size or shape in last chambers. Each of the three analysed samples is characterized by a different foraminiferal assemblage: Elphidium aculeatum assemblage, Hauerinidae assemblage and Lobatula lobatula assemblage. These assemblages are characteristic for a shallow marine environment. Low taxonomic diversity and high dominance or monospecific foraminiferal assemblages indicate generally a restricted marine environment. It seems that the increasing salinity and very high-energy environment were the most probable factors controlling the composition of the foraminiferal assemblages.
PL
Górnobadeńskie rafy koralowe zachodniej Ukrainy posiadają kawerny o przekroju do 1 m oraz szczeliny, które obecnie są wypełnione osadami sarmackimi – iłami marglistymi i zasilonym piaskiem węglanowym i bioklastycznym, często mszywiołowym. Osady te często zawierają liczne i bardzo dobrze zachowane węglanowe otwornice bentosowe; nie stwierdzono natomiast otwornic zlepieńcowatych. Dość częste są skorupki z morfologicznymi nieprawidłowościami, np. formy bliźniacze albo skorupki z nieregularnością rozmiaru lub kształtu ostatnich komór. Każda z trzech próbek zawiera inny zespół otwornicowy: w pierwszej występuje zespół z Elphidium aculeatum, druga zawiera zespół z Hauerinidae, a trzecia – zespół z Lobatula lobatula. Wszystkie te zespoły są charakterystyczne dla środowiska płytkomorskiego. Niskie zróżnicowanie taksonomiczne i wysoka dominacja lub jednogatunkowe zespoły otwornicowe wskazują na ogólnie ograniczone środowisko morskie; wydaje się, że w takich warunkach najbardziej prawdopodobnym czynnikiem warunkującym skład zespołów otwornicowych było podwyższone zasolenie i środowisko bardzo wysokoenergetyczne.
EN
Detailed micropaleontological investigation of more than 400 samples (150 identified species) from the Mesozoic sediments of southern Poland and southwestern Ukraine was the basis for their correlation. The youngest Mesozoic assemblage identified in the studied material represent the early Late Cretaceous (Turonian). This assemblage occurs in the so-called the III Formation of Turonian epicontinental strata in Poland, and in the Dubivtsi Formation in West Ukraine. Microfossil assemblages of the Early Cretaceous age (Berriasian–Barremian) allow for a correlation of the Ropczyce and Dębica formations (central part of S Poland) and the upper part of the Babczyn and Cieszanów formations (SE Poland) with the Stavchany Formation and a part of the Bukovyna Formation in SW Ukraine. Tithonian microfossil assemblages from Poland resemble those of the shallow-water Nyzhniv Formation from the Ukrainian part of the East European Platform. Open-marine microfossils (e.g. calpionellids) commonly occur only in the Ukrainian material. Poor microfossil assemblages of the Kimmeridgian age occur in majority of studied subdivisions. They were identified in the Sobków Formation and the upper part of the Niwki Formation in the central part of S Poland, Ruda Lubycka, the upper part of the Bełżyce, Basznia, and Głowaczów formations (SE Poland) and in the Moryantsi and Pidluby formations (Bilche-Volitsia zone of the Carpathian Foredeep) and in the Rava Rus’ska Formation (Eastern European Platform). Among the Oxfordian microfossil assemblages, only those containing Alveosepta jaccardi (Schrodt) and Protomarssonella jurassica (Mityanina) allow for a correlation of subdivisions from both areas. These assemblages occur in the “Coral-algal” Formation in the Tarnów–Dębica region and in the Bełżyce, Jasieniec and Jarczów formations in SE Poland. The coeval sediments belong to the Boniv, Rudky and Sokal formations in West Ukraine. Scarce data from the Middle Jurassic sediments do not allow for a correlation of the material studied.
PL
Szczegółowa analiza mikropaleontologiczna ponad 400 próbek (150 oznaczonych gatunków) z utworów mezozoicznych południowej Polski i zachodniej Ukrainy umożliwiła korelację tych utworów. Najmłodsze stwierdzone, w badanym materiale, zespoły reprezentują niższą późną kredę (turon). Zespół ten występuje w tzw. III formacji utworów epikontynentalnych w Polsce oraz w formacji dubowieckiej SW Ukrainy. Zespoły mikroskamieniałości wieku wczesnej kredy (berias–barrem) pozwalają na korelację formacji z Ropczyc i Dębicy (centralna część Polski południowej) oraz górnej części formacji z Babczyna i formacji cieszanowskiej (SE Polska) z formacją stawczańską i częścią formacji bukowińskiej SW Ukrainy. Stwierdzone w materiale z Polski zespoły mikroskamieniałości tytonu przypominają zespoły z płytkowodnych utworów formacji niżniowskiej ukraińskiej części platformy wschodnioeuropejskiej. Natomiast większość zespołów mikroskamieniałości tytonu z badanych utworów SW Ukrainy charakteryzuje obecność form otwartego morza (kalpionellidów). Zespoły mikroskamieniałości kimerydu, choć ubogie,występują w większości badanych utworów. Stwierdzono je w formacji z Sobkowa i w górnej części formacji z Niwek (centralna część Polski południowej) w formacji z Rudy Lubyckiej oraz w górnych częściach formacji bełżyckiej, z Baszni, głowaczowskiej (SE Polska), a także na Ukrainie w formacjach moranieckiej i podlubieckiej (strefa Bilcze-Wolica zapadliska przedkarpackiego) i w formacji z Rawy Ruskiej (platforma wschodnioeuropejska). Z zespołów oksfordu jedynie te, które zawierały otwornice Alveosepta jaccardi (Schrodt) i Protomarssonella jurassica (Mityanina), pozwalają na korelację badanych wydzieleń litostratygraficznych. Zespoły takie występują w formacji „koralowcowo-glonowej” rejonu Tarnów–Dębica (centralna część Polski południowej) oraz w formacjach bełżyckiej, jasienieckiej i jarczowskiej (SE Polska). Na obszarze SW Ukrainy do równowiekowych utworów należą formacje: boniwska, rudkowska i sokalska. Niedostateczna ilość danych mikropaleontologicznych z utworów jury środkowej nie pozwoliła na wykonanie korelacji.
EN
The faunal dynamics of benthic foraminifera in the Middle Jurassic ore-bearing clays of Gnaszyn (Kraków-Częstochowa Upland, south-central Poland) are used to reconstruct sedimentary environments. Two types of foraminiferal assemblages, distinct in their quantitative and qualitative composition, were distinguished; type I assemblages, characterizing intervals between horizons with sideritic concretions; and type II assemblages, characterising horizons with sideritic concretions. Benthic foraminifers were further subdivided into eight ecological morphogroups, based on their morphological features and micro-habitats. Type I assemblages consist mostly of plano/concavo-convex, small-sized epifaunal morphotypes, with a restricted occurrence of shallow infaunal forms and a scarcity of deep infaunal taxa, which suggests low-oxygen conditions in both sediment and bottom waters, and a high sedimentation rate in an outer shelf environment. Type II assemblages are characterized by high taxonomic diversity, high specimen abundance and variability of epifaunal and infaunal morphotypes representing a mixed group of specialized feeding strategies. This suggests optimum living conditions controlled by a lower sedimentation rate, relatively well-oxygenated bottom waters and sufficient or high food supply.
EN
The Karpatian-Badenian (Burdigalian-Langhian, Early-Middle Miocene) transition is a key interval in the evolution of the Paratethys and the proto-Mediterranean Sea. We present here, based on the Wagna section (Styrian Basin, Central Paratethys), a study of a quantitative analysis of the microfossils (foraminifera and calcareous nannofossils) and a statistical treatment of data to reconstruct the palaeoenvironmental condition during this time. During the Karpatian, relatively deep water, cool conditions with a relatively high nutrient input prevailed in the Styrian Basin, as suggested by the high abundance of cool-water foraminifera and calcareous nannofossils. The Badenian was generally warmer, with a lower availability of nutrients, and was characterized by carbonate units and patch reefs and associated microfossil assemblages (e.g., Eponides spp.). Riverine plumes brought fresh water into the Styrian Basins during the Badenian and induced high productivity and the proliferation of species highly tolerant of low salinity such as Ammonia tepida. The passage from calcareous nannofossil Zone NN4 to NN5 is characterized by a reorganization of water masses and the transition from cooler and nutrient-rich to warmer and nutrient-poorer waters. Based on the microfossil abundance trends we interpret the planktonic foraminiferal species Globigerina tarchanensis as preferring cooler nutrient-rich waters and Reticulofenestra minuta as preferring warmer and nutrient-poor waters. The application of cluster analysis based on the Bray-Curtis Similarity and non-metric MultiDimensional Scaling (nMDS) adds important information to that obtained only from microfossil abundance curves, enabling identification of cryptic trends and correlation with sequence stratigraphy. This method may even complement biostratigraphic interpretation and support age attribution in the Paratethyan area, where marker species are missing.
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Content available remote Zagadka późnokredowego wymierania
PL
Artykuł skupia się na problemie jednego z największych kryzysów świata organicznego w dziejach Ziemi, mającego miejsce na granicy kredy i paleogenu, w wyniku którego wyginęło wiele grup zwierząt, m.in. znane wszystkim dinozaury. W artykule ukazano poglądy różnych badaczy, wyjaśniające późnokredowe wymieranie, skupiając się w znacznej mierze na dominującej obecnie teorii impaktowej, sprecyzowanej przez Waltera i Luisa Alvarezów. Artykuł ten jest pewnego rodzaju śledztwem, w którym podjęto próbę rekonstrukcji wydarzeń z końca kredy oraz wskazano ofiary, które nie przetrwały zmian środowiska, zachodzących pod koniec mezozoiku. Ponadto ukazano dowody geologiczne i paleontologiczne, potwierdzające teorię Alvarezów, nie omijając danych, które przemawiają za pozostałymi hipotezami.
EN
The article discusses one of the direst crises in the history of the organic life on Earth. The event that took place at the Cretaceous/Paleogene transition (65 MY ago) was the cause of mass extinction of many animal species including well known dinosaurs. The article reviews hypotheses of various scientists explaining late Cretaceous demise focusing on the prevailing impact theory by Luis and Walter Alvarez. This essay is sort of investigation where the author attempts to reconstruct the events of the Upper Cretaceous Period. It also presents the victims that were unable to adapt to environmental changes of the late Mesozoic Era. Moreover, the article presents geological and paleontological arguments for Alvarez' theory without omitting the evidence that supports alternative theories.
PL
W pracy przedstawiono charakterystykę stratygraficzną dolnych łupków i wapieni cieszyńskich w oparciu o zróżnicowane spektrum mikroskamieniałości. Rozmieszczenie i migracja tych mikroorganizmów do basenu cieszyńskiego, usytuowanego na południowej krawędzi Platformy Zachodnioeuropejskiej, były określone jego geotektoniczną transformacją. Pozycję niefliszowych, węglanowych utworów basenu (dolne łupki cieszyńskie i dolna część wapieni cieszyńskich) określają zespoły tytońskich mikroskamieniałości z pojedynczymi elementami późnego kimerydu. Natomiast sedymentacja węglanowych turbiditów (wyższa część wapieni cieszyńskich) miała miejsce głównie w okresie berias - walanżyn z prawdopodobną kontynuacją do (?późnego) hoterywu.
EN
Microfossils from the Tithonian-(?Late) Hauterivian carbonate deposits of the Cieszyn Beds (Lower Cieszyn Shales and Cieszyn Limestones) are reviewed. The distribution and migration of microorganisms into the Carpathian (Cieszyn) Basin were determined by geotectonic transformation of the Cieszyn Basin situated on the southern margin of the Western European Platform. The age of the nonflysch carbonate deposition in the Cieszyn basin (Lower Cieszyn Shales, and lower part of the Cieszyn Limestones) is documented by Tithonian calcareous microfossils accompanied by Late Kimmeridgian elements whereas the development of carbonate turbidite deposition in the Beriassian - Valanginian time (Cieszyn Limestones), probably continued up to the (?Late) Hauterivian.
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