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Nannofossils and planktonic foraminifers from the Lower Miocene Alkun Formation of central and western Ciscaucasia were studied in the following sections: the stratotype section on the Alkunka River, the Republic of Ingushetia; stratotype of the Caucasian Regional Stage on the Kuban River, Karachay-Cherkessia; Lower Miocene reference section on the Belaya River, Adygea; and in the sections of the Alkun Formation stratotype area on the Fiagdon and Mairamadag rivers, North Ossetia. Planktonic foraminifers in the Alkun Formation were studied for the first time. The available results made it possible to reveal the composition and structure of nannofossil and planktonic foraminiferal assemblages from the Alkun sediments in Ciscaucasia, to refine their stratigraphic and correlation potential and to recognize bionomic conditions of the Alkun basin in the studied area. As a result of the nannoplankton study the Cyclicargolithus floridanus Beds were recognized in the Alkun Formation and, taking into account the occurrence of the zonal species Triquetrorhabdulus carinatus along with Tr. milowii, they are correlated with the upper (Miocene) part of the Aquitanian Zone NN1. Planktonic foraminiferal data permitted to recognize the Streptochilus pristinum Beds. [ABSTRACT FROM AUTHOR]

A comprehensive study of the Maastrichtian–Danian boundary rocks in the Klementyev Mountain section (eastern Crimea) was carried out. The lithological characteristics of carbonate, carbonate–clayey, and clastic rocks are scrutinized. The dynamic of changes in the benthic and planktonic foraminiferal assemblages is analyzed. The geochemical and isotopic data were obtained for this section for the first time. The stratigraphic range of the upper Maastrichtian and lower Danian has been specified. The late Campanian–early Maastrichtian age of the underlying rocks has been confirmed for the first time. Sediments of the Klementyev Formation were deposited in a deep-sea pelagic paleoenvironment on the submerged part of the outer shelf, whereas the overlying Lower Danian sediments were deposited in shallow waters of the inner shelf with terrigenous sedimentation and high hydrodynamic activity. [ABSTRACT FROM AUTHOR]

• Sahune (Oxfordian, Late Jurassic) in south-eastern France Basin is newly described. • Carbonate bodies enclosed within Terres Noires Formation formed at cold seeps. • Associated fauna indicate seepage at bathyal depth ca. 1.500 m. • Several seep ostracod families have evolved at seeps since the Oxfordian. • Colonization of bathyal environments occurred earlier than thought. Hydrocarbon seeps represent some of the most extreme marine habitats but are also home to rich communities developed around chemosynthesis rather than photosynthesis. Here we describe the outcrop of Sahune (Drôme department, south-eastern France), that illustrates a new seeping site during the Late Jurassic (middle Oxfordian), as formally demonstrated by geochemical proxies. We report the associated fauna composed of foraminifers, radiolarians, crinoids, echinoids and ostracods that all point to seepage at bathyal depth. The foraminifer assemblage and the occurrence of the irregular echinoid Tithonia oxfordiana together point to a middle Oxfordian age. We provide an in-depth analysis of the ostracod community, which is the oldest so far reported in such environments. The new species Procytherura praecoquum may be cognate to the seepage site and could illustrate the oldest known example of pore clusters, sometimes proposed as representing ectosymbiosis. The Sahune assemblage demonstrates that cold seep ostracod communities were already a mixture of taxa from platform and deep-sea oligotrophic environments. The post-Jurassic diversification of ostracods at cold seeps was related to colonization events and diversification of families that have been inhabitants of such ecosystems at least since the Oxfordian. The Sahune record changes our current conception of the deep-sea colonization by the ostracods Tethysia and Procytherura that occurred earlier than traditionally considered. [ABSTRACT FROM AUTHOR]

Stratigraphy of Campanian deposits in the stratotype of the Kudrinskaya Formation in the Southwestern Crimea is revised. For the first time, integrated sedimentological, biostratigraphic (ichnofossils, cephalopods, inoceramids, foraminifers, dinocysts, nannoplankton, gilianelles), isotope-geochemical, paleo- and petromagnetic characteristics of the section were obtained. The boundary of the lower and upper Campanian is substantiated and confirmed by U–Pb dating of zircons from the well-known bentonite (kil) clay bed in the interval of 77–80 Ma. It is proposed to accept the Campanian Substage boundary of the General Stratigraphic Chart (for bipartite stage subdivision) at the top of the Chron C33r, located near the δ13C isotopic excursion "MCaE" – Mid-Campanian Event, near the first occurrence of the benthic foraminifer Brotzenella monterelensis and a number of other traditional biomarkers. [ABSTRACT FROM AUTHOR]

A silicite horizon corresponding to the global catastrophic event at the Cretaceous–Paleogene boundary was found for the first time in the flysch sequence of the Shapsug section on the southern slope of the Northwest Caucasus. Assemblages of radiolarians and planktonic foraminifers dating the host beds were identified. Mineralogical and analytical data support the presence of tectites, impact minerals, and increased iridium content in the boundary bed of the studied section. [ABSTRACT FROM AUTHOR]

The article describes four species of agglutinated foraminifers belonging to three genera (Verneuilina, Orbignyna, and Spiroplectammina) three superfamilies (Verneuilinoidea, Ataxophragmoidea, and Spiroplectamminoidea) and two orders (Ataxophragmiida and Ammodiscida, suborder Textulariina). Benthic species of foraminifers play an important role in the stratigraphic subdivision of the Upper Cretaceous deposits of the Northern outskirts of Donbas and correlation with adjacent territories, as they make up the most part of the assemblage in the samples. For this region, the foraminifera species Verneuilina muensteri Reuss, 1854, Orbignyna variabilis (d’Orbigny, 1840), Orbignyna pinguis Woloschyna, 1961, and Spiroplectammina baudouiniana (d’Orbigny, 1840) were monographically described for the first time. For each species of foraminifers, a detailed description of shell morphology is given. According to the biozonal scale of the Upper Cretaceous deposits of the East European Platform, Verneuilina muensteri is one of the characteristic species of the Upper Turonian Gavelinella moniliformis s. l. foraminifer zone, the species Orbignyna variabilis is typical for the Upper Santonian Gavelinella stelligera zone, and the species Orbignyna pinguis is characteristic of the Upper Campanian Globorotalites emdyensis zone. The species Spiroplectammina baudouiniana is also described. The stratigraphic and lateral distribution of each species of agglutinated foraminifers is indicated, and the deposits and sections of the Northern outskirts of Donbas in which they occurred are indicated. A schematic map of the region is presented, showing the studied sections in which shells of these species were found. These species are found in the rocks of the Shyroka, Yelanchyk, Kryva Luka, Sydorove, Konoplyanivka, and Kamianyi Brid formations of the Northern outskirts of Donbas, which are represented by chalk, marls, and calcareous sandstones. The work presents images of foraminifer species taken with a scanning electron microscope JSM-6490LV (JEOL Ltd., Japan). The article deepens our knowledge of some agglutinated foraminifers from the Upper Cretaceous deposits of the Northern outskirts of Donbas, which are characteristic species of the zone, contributing to further solving the issues of stratigraphy and correlation of these deposits.

Microfossils of the Strenoceras niortense Zone of the Upper Bajocian of the Karachay-Cherkessian Republic are studied. The zone is represented mainly by dark gray silty-sandy clays, with scattered nodules often arranged in interbeds, and belongs to the lower part of the upper subformation of the Djangura Formation. The taxonomic composition and distribution of foraminifera, ostracods, dinoflagellate cysts, and miospores in the section has been identified. The ranges of biostratigraphic units based on foraminifera, ostracods, and dinocysts are emended and these units are correlated with the ammonite scale. The distribution of benthic foraminifers indicates that these are Beds with Ophthalmidium caucasicum, comparable with the entire Niortense Zone and most of the Garantiana Zone. The Beds with Globuligerina dagestanica established using planktonic foraminifera are correlated with the entire studied interval from the Niortense Zone to the Lower Bathonian, inclusive. In the middle-upper part of the Niortense Zone (Rostovtsevi and Baculatum Subzones), the Beds with ostracods Palaeocytheridea (Malzevia) subtilis were recognized for the first time. The beds with dinocysts Carpathodinium predae, Rhynchodiniopsis? regalis, Meiourogonyaulax valensii are correlated with the range of the Niortense and Garantiana Zones and the lower part of the Parkinsoni Zone, inclusive. Characteristic taxa of microfauna and dinocysts are illustrated. [ABSTRACT FROM AUTHOR]

The study of a core of borehole 8 drilled in the town of Maloyaroslavets to a depth of 94 m has made it possible to obtain the biostratigraphic characteristics of the Tarusian and Protvian regional substages of the Serpukhovian Stage and lower part of the Vereian Regional Substage of the Moscovian Stage based on foraminifers and conodonts. The Tarusian Regional Substage is attributed to the Neoarchaediscus postrugosus Zone. The Eostaffellina paraprotvae Zone has been established in the Protvian Regional Substage, and a deep-water conodont assemblage of the Gnathodus bollandensis Zone has been found in its upper part (6.8–12.0 m above the base). The generalization of all data on conodonts of the Protvian Regional Substage of the Moscow Syneclise has shown that it contains at least four transgressive–regressive cyclites. The type locality of the species Eostaffellina protvaeensis has been specified in the Tetyuevo section in the Rzhev Volga region. A rich assemblage of conodonts from the Vereian Alyutovo Formation of the Moscovian Stage belongs to the Declinognathodus donetzianus Zone. [ABSTRACT FROM AUTHOR]

The results of a comprehensive study of an Upper Maastrichtian reference Mt. Klementyev section (Southeastern Crimea), consisting of a terrigenous–carbonate sequence, are presented. It is established that sedimentation occurred in relatively deep-sea conditions. Biostratigraphic analysis of assemblages of benthic and planktonic foraminifers made it possible to recognize the foraminiferal zones in the section and to confirm deep-sea sedimentation during this period. [ABSTRACT FROM AUTHOR]

Rhodolith-forming non-geniculate coralline red algae have been recorded from the Long Formation, exposed in four different outcrops at Little Andaman Island (Hut Bay) in the northeastern Indian Ocean. The non-geniculate corallines are represented by species of Sporolithon Heydrich, 1897, Mesophyllum Lemoine, 1928, Lithothamnion Heydrich, 1897, Phymatolithon Foslie, 1898, Lithoporella (Foslie) Foslie, 1909, Spongites Kützing, 1841, Neogoniolithon Setchell & Mason, 1943 and Lithophyllum Philippi, 1837. The algal assemblages also include geniculate corallines belonging to the genera Amphiroa Lamouroux, 1812 and Corallina Linnaeus, 1758. In addition, larger benthic foraminifers and few planktonic foraminifers also have been identified in thin section analysis. Based on the earlier study carried out on planktonic foraminifers, the Long Formation has been dated as Serravallian (late middle Miocene) and chronostratigraphically, the Long Formation has been included in the Ongeian Regional Stage. In the rhodolith-forming non-geniculate corallines, various growth forms and taphonomic features have been recognized. Diagenesis affected the studied material by micritization, cementation and compaction. The four outcrops are dominated by bioclastic wackestone and packstone composed of coralline red algae, benthic and planktonic foraminifers, echinoid spines and unidentified coral fragments. The rhodolith-forming coralline red algae, the growth forms and taphonomic features in non-geniculate corallines and the characteristic benthic foraminifers are indicative of a moderate energy depositional environment. This study indicates that the carbonate production was considerably high during the Serravallian of the tropical northeastern Indian Ocean. [ABSTRACT FROM AUTHOR]

Olena Semenivna Lypnyk is a well-known specialist micropaleontologist of Ukrainian paleontological science, a student of the Doctor of Geological and Mineralogical Sciences, Professor O.K. Kaptarenko-Chernousova, senior researcher of the Department of Stratigraphy and Paleontology of Mesozoic deposits of the Institute of Geological Sciences of the National Academy of Sciences of Ukraine, Candidate of Geological and Mineralogical Sciences. The article presents the biography and scientific achievements of O.S. Lypnyk, who was engaged in the biostratigraphy of the Upper Cretaceous deposits of the platform Ukraine by foraminifers, in particular, the Upper Cretaceous sediments of the Dnieper-Donetsk depression and the outskirts of Donbas. O.S. Lypnyk is the developer and co-author of the zonal dissection of the Upper Cretaceous deposits of the East European Platform by benthic foraminifers, the developer and author of the zonal scale of the Upper Cretaceous sediments of the Dnieper-Donetsk depression by benthic foraminifers, the author of the division of the Upper Cretaceous stratum of the Dnieper-Donetsk depression into suіtes, one of the authors of the regional stratigraphic scheme of the Upper Cretaceous deposits of the Dnieper-Donetsk depression, as well as the outskirts of Donbas. The assessment of the scientific heritage of Olena Semenivna Lypnyk is given. The research was based on the personal file and autobiography of O.S. Lypnyk; photos from the archives of the Institute of Geological Sciences of the National Academy of Sciences of Ukraine and the Doctor of Geological and Mineralogical Sciences, Professor D.E. Makarenko; and memories of employees of the institute. [ABSTRACT FROM AUTHOR]

A lithofacies and bionomic study of the Artinskian–Kungurian boundary deposits of the Cisuralian Series of the Permian System in the Yuryuzan–Ai Depression was carried out with reference to the Mechetlino section (Southern Urals). This section was a candidate for GSSP of the lower boundary of the Kungurian Stage. Eight lithological facies rock types, or lithofacies, were recognized in terrigenous–carbonate deposits. On the basis of their combinations, the section was divided into packages composed of carbonate–terrigenous flysch rocks, detrital carbonate deposits initiated by storms, and blocky submarine slump deposits. Six ecological assemblages of small foraminifers, reflecting depositional environments in benthic fauna source areas, were identified. The mechanisms of mixing and transport of plant remains along with benthic, planktonic, and nektonic fauna remains are indicated. A model of formation of the Lower Permian sedimentary assemblages in the Yuryuzan–Ai Depression of the Ural foredeep, reflecting the bionomic specificity of the assemblages of biogenic remains in the boundary interval of the Artinskian and Kungurian stages, is proposed. [ABSTRACT FROM AUTHOR]

The Viséan–Serpukhovian boundary is poorly defined in South China, hampering regional and global stratigraphical correlations. The foraminiferal and conodont distribution of the Baping Formation in the carbonate-slope Danlu section permits the recognition of an interval from the middle Viséan to the uppermost Serpukhovian in a continuous succession. The base of the Serpukhovian in Danlu is recognized by the first occurrences of Janischewskina delicata , Howchinia subplana and questionable ' Millerella ' tortula. At a slightly younger level, the conodont Lochriea ziegleri is first recorded. A calibration on the first occurrence of L. ziegleri in different basins at a global scale has been revised compared to auxiliary markers within the ammonoids and foraminifers. The late occurrence of L. ziegleri in the Danlu section also supports a lack of synchronicity in the global first occurrence of this taxon. This study calls for the recognition of a new base for the Serpukhovian under a far better correlation between different zonal schemes and fossil groups. [ABSTRACT FROM AUTHOR]

This paper presents the results of micropaleontological studies of stones that were found during the study of the pier of the ancient Greek city of Phanagoria. Foraminifers of the Late Turonian, Coniacian, Campanian, and Maastrichtian, which are characteristic of Central Tethys zones, have been recorded in the samples. This makes it possible to exclude the Crimean–Caucasian region from the possible regions of origin of the material. The absence of signs of deformation and metamorphism in the studied rocks may indicate their origin outside the Aegean Sea area. The closest areas to the studied rocks with respect to genesis and geochronology are Upper Cretaceous carbonate strata on the southern coast of the Black Sea near the ancient cities of Heraclea and Sinope. [ABSTRACT FROM AUTHOR]

Human-induced carbon emissions are altering the modern climate, with severe repercussions on ecosystems. Among others, anthropogenic pressure is causing deoxygenation of the bottom water, with the widespread establishment of hypoxic zones in several Mediterranean areas. The geological archives allow investigating past deoxygenation dynamics (sapropel events) and their impact on marine ecosystems. Here, we compare the causes and the evolution of deoxygenation dynamics which occurred during two different time periods (Messinian and Holocene) in different paleoceanographic settings based on their micropaleontological content. The Messinian sapropel events are the result of increased export productivity during a relatively cold and arid context, triggering bottom anoxic conditions. The Holocene sapropel formed in response to weakening/stopping of the thermohaline circulation due to increasing temperature and freshwater input. Our results suggest that the deoxygenation dynamics in the Mediterranean in the near future will not follow the trend characteristic of the Holocene deep-sea sapropel because of the predicted drying trend. Differently, the paleoceanographic setting triggering the Messinian shallow-sea sapropels is comparable with the modern situation in different Mediterranean areas, where human-induced eutrophication is promoting deoxygenation. Based on these results, we suggest that the patchy deoxygenation trend in the Mediterranean Sea caused by climate warming may lead to a drastic change in the ecosystem services which would likely impact human activities. [ABSTRACT FROM AUTHOR]

Ten foraminiferal zones are proposed in the Youjiang Basin (South China): Pojarkovella, Pojarkovella nibelis-Endothyranopsis compressa, Cribrospira panderi-Eostaffella ikensis, Climacammina, Janischewskina delicata, Eostaffellina decurta, Bradyina cribrostomata, Eostaffellina actuosa-Eostaffellina protvaensis, Plectostaffella and Pseudostaffella antiqua zones. These zones span the interval from the middle Viséan to the late Serpukhovian in a continuous succession, and above, a final zone characteristic of the Severokeltmian Substage in the middle part of the early Bashkirian. These zones are compared with other foraminiferal zones described from China, particularly with those from South China and allow to uniformize the foraminiferal stratigraphical records in the region, and to standardize the foraminiferal zones defined in those regions. The stratigraphical range of some taxa is still debated, but the Viséan-Serpukhovian and the lowerupper Serpukhovian boundaries are well constrained by well-known cosmopolitan taxa. Foraminifers during the lower Middle Mississippian (middle Viséan to the earliest late Viséan) are more similar to the foraminiferal assemblages described from Western Europe, whereas from the upper Middle to Late Mississippian (i.e. latest ViséanSerpukhovian) are more similar to those in the Russian Platform, and thus, the use of the Russian zonal scheme and biostratigraphy is more practical than to use the biozones defined in Western Europe. [ABSTRACT FROM AUTHOR]

The impacts on ostracods and foraminifers caused by three Late Quaternary ashfalls of different intensities and recovered in the ANTA02-NW2 core sediments (Drygalski Basin, western Ross Sea) were analysed for the first time. Albeit with different timing, both associations demonstrated similar response patterns associated with the deposition of material from volcanic eruptions. In particular, based on the palaeontological evidence, it was possible to divide the cores into four intervals/phases recording the evolution of the ecosystem before and after the deposition events: (1) Pre-extinction phase (high abundance and high diversity values). (2) Extinction phase, characterised by the complete disappearance of ostracod fauna; the foraminiferal assemblage, although not entirely absent, records extremely low values of abundance and diversity (survivor assemblage). (3) Recovery phase (increasing abundance and diversity values), characterised by the recolonisation of some opportunistic taxa; species such as Australicythere devexa and Australicythere polylyca dominate the ostracod assemblage. (4) Post-extinction phase (high abundance and high diversity values), with the return to an environmental equilibrium characterised by the colonisation of specialised taxa such as Argilloecia sp., Cytheropteron sp., Echinocythereis sp., and Hemicytherura spp. Our results may aid in the understanding of how communities (i.e., ostracods and foraminifers) recovered after the impact of direct deposits of volcanic ash into ocean waters. The mechanisms by which disappearance and/or mortality was induced are still not clear. The release of toxic metals during the reaction of the volcanic ash with seawater, the resulting chemical alteration in the seawater, and the change in pH, together with the possible suppression of planktonic organisms, may have caused the two main extinction phases recorded by the ANTA02-NW2 core sediments. [ABSTRACT FROM AUTHOR]

The stratigraphic scale of the Eastern Paratethys is revised based on a study of the Neogene stratotype and reference sections, their biotic characteristics, and paleomagnetic and sedimentological data. New data on the correlation of its regional subdivisions with the Central Paratethys and Mediterranean stratotypes are presented. The section "Regional Stage Scale of the Eastern Paratethys" considers the history of identification and a brief description of the horizons of the regional scale, which later became regional stages, as well as their historical stratotypes and lectostratotypes, and division into Beds and Substages. The section "History of Separate Biota Groups" provides reviews on the most important groups of fauna, phytoplankton, and terrestrial vegetation, as well as on magnetostratigraphy, the possibility of correlation and dating of sections based on these data, and comparison with the Central Paratethys and stratotypes of the Mediterranean. In conclusion, the main results of the revision of the stratigraphic scheme of the Neogene of the Eastern Paratethys are given. [ABSTRACT FROM AUTHOR]

Carboniferous-Permian successions in the Amotape Mountains (NW Peru) are poorly dated due to the predominant siliciclastic intervals and the scarcity of fossils. The biostratigraphy of the formations is thus poorly constrained and, in general, limited to major systems or subsystems. The Cerro Prieto Formation was assigned to the Pennsylvanian or middle Pennsylvanian, but at the Caseta de la Antena section, the lower half of the formation contains carbonate horizons where diverse foraminiferal assemblages are recorded. Foraminifers allow to assign the base of the formation to the basal Bashkirian Stage, Morrowan Substage or Globivalvulina-Millerella Zone. This biostratigraphy can be extrapolated to the base of the Tarma Formation in central and south Peru, where this part of the latter formation remains undated. The upper limestone levels at Caseta de la Antena are assigned to the late Bashkirian, Atokan Substage or Eoschubertella-Pseudostaffella Zone. The upper half of the Cerro Prieto Formation, only composed of siliciclastics, might correspond to the uppermost late Bashkirian/lowermost Moscovian, or the mid-upper Atokan, due to fusulinids recorded at the top of the Tarma Formation. Foraminiferal assemblages are rather similar to those recorded from the lower part of the Copacabana Formation in Bolivia, although some differences occur, and apparently rather different from those in south Peru, a fact which suggests a slight biogeographic differentiation between the Amotape Mountains and the Central Andean Belt possibly related to its distinct geological setting. • Middle Carboniferous Foraminiferal assemblages from Peru are similar to those in Bolivia. • The Globivalvulina-Millerella and Eoschubertella-Pseudostaffella zones occur. • The Cerro Prieto Formation is Baskhirian to Moscovian. • Differences in the foraminiferal assemblages support a continental-margin forearc setting. [ABSTRACT FROM AUTHOR]

Abstract A foraminiferal faunal study was carried out in a Holocene marine section from Arroyo Baliza, located on the northwest coast of the Beagle Channel, to contribute to the knowledge of the palaeoenvironmental conditions during the marine Holocene event. Foraminiferal assemblage was represented by 32 species distributed among 21 genera. The assemblage was dominated by Elphidium macellum (Fichtel & Moll) Elphidium alvarezianum (d’Orbigny), Cribroelphidium excavatum (Terquem) and Buccella peruviana (d’Orbigny), accompanied by Cibicides fletcheri Galloway & Wissler and Cibicidoides dispars (d’Orbigny) in low proportion. The predominance of Peridiniales dinocysts in the marine palynomorphs assemblage, suggested inner neritic conditions with cooler and more nutrient-rich waters. The distribution of the foraminiferal species was variable throughout the section indicating palaeoenvironmental changes in Arroyo Baliza between 3499–2595 cal yr BP. A gradual passage from high energy, cold and well-oxygenated marine waters towards a shallower environment with low energy and low to moderate salinity of the waters were linked to the regressive phase. This study complements and supports the previous palynological data from this section, which reflects an increase in number and diversity of dinocyst species indicating marine environmental conditions during the late Holocene as it exists today in the Beagle Channel.

A well‐developed 86 m‐thick Cenozoic sedimentary succession in the Matanomadh area, western Kachchh, was studied to assess the stratigraphic positions of different units, ascertain depositional environments, and the degree of climatic controls over time depositional processes. Age‐diagnostic nannoplankton species Cyclicargolithus floridanus (46.29–12.1 Ma), Reticulofenestra dictyoda (53–30.8 Ma), Reticulofenestra minuta (50.5–2.59 Ma) and foraminiferal species, for example, Orbulinoides beckmanni (41–39.5 Ma) found across studied units envisage the stratigraphic age and palaeoenvironment. CaO with strong negative elemental correlation, binary/ternary discriminant tectonic and depositional regimes cross‐plot from units indicate the biogenic origin of limestones and shales were formed in typical passive, marginal, shallow littoral settings with plausible detritus influx from Deccan basaltic provenance. Total organic carbon with TE‐REE respectively connotes a sedimentation process in a nearly consistent open shallow marine, locally transient semi‐restricted marginal basin in a tropical‐equatorial region. Furthermore, principal component analysis (PCA) of weathering indices based on elemental abundance and X‐ray diffraction data of clays deterministically suggest with empirical relation between humid tropical climate‐induced weathering and fluctuant terrestrial influx. Palaeoredox indices with biological data demonstrate localized redox‐stratified conditions. However, coherent signatures of the global events such as Eocene Thermal Maximum‐2, Middle Eocene Climatic Optimum, and Mid Miocene Climatic Optimum can be traced and validated by synthesizing geochemical data for direct/indirect estimation of sediment routing, rainfall (αAlMg and αAlCa) and climate proxies (PCA), productivity indices (Babio, Cubio and Nibio), and localized periodic oxic‐dysoxic environment (V/Cr, U/Th, Ni/Co) from core samples. [ABSTRACT FROM AUTHOR]

The Devonian–Carboniferous boundary beds in the Berchogur (Birshogyr) sections in the Mugodzhary (Mugalzhary) Mountains in western Kazakhstan, known to contain various fossil groups, including ammonoids, conodonts, foraminifers, corals, crinoids, and trilobites, are re-examined. The siliciclastic-carbonate succession of the Zhangana Formation reveals the presence of several ammonoid, conodont, and foraminiferal zones. The succession contains the Acutimitoceras ammonoid Genozone, equivalent to the level of the Stockum ammonoid fauna of Germany, with the conodont Siphonodella sulcata appearing within the Genozone. The same beds show mass occurrences of the foraminifer Tournayellina pseudobeata. The study of the Berchogur sections began in the 1980s; these sections are among very few successions globally with ammonoids of the Acutimitoceras Genozone in association with conodonts and foraminifers. At that time, several outcrops in a small area in the upper reaches of Burtybai (Zhangansai) Creek and two boreholes drilled near the sections were studied, and new taxa of ammonoids, foraminifers, ostracods, conodonts, algae, and spores were described. New excavations in 2018–2020, in conjunction with a search for a new definition of the Devonian–Carboniferous boundary, provided abundant new information on these taxa, on the lithology, and on crinoids, trilobites, and corals. The exact position of marker fossils and lithological changes are documented in several sections along Burtybai Creek allowing an amended correlation with sections of the D–C boundary beds in Western Europe. [ABSTRACT FROM AUTHOR]

A foraminifer assemblage has been studied from clay pulp of the Shugo mud volcano in the Kerch–Taman volcanic area (Taman Peninsula) to refine the stratigraphic section of this region. The mud volcanic breccia contains the foraminifera shells of the Miocene, middle Eocene (Lutetian), and Late Carboniferous (Santonian, Campanian, Maastrichtian) species. The shells of the Neogene and Paleogene foraminifers exhibit good preservation. The worse preservation of the Cretaceous shells can be related to the composition of host rocks, which probably include terrigenous and carbonate-terrigenous turbidites. The finding of relict Late Cretaceous and Middle Eocene foraminifers in the clay pulp indicate the presence of sequences of this age in the section. [ABSTRACT FROM AUTHOR]

Biostratigraphy and sedimentology of the Pelsonian (Middle Anisian) carbonate Jelovica Fm sequence have been documented in detail in the Spomen Dom section (Jelovica-Visočka Ržana region of the Stara Planina Mts, Eastern Serbia). Abundant ammonoids and foraminifers, together with rare brachiopods, nautiloids, bivalves and crinoids characterize faunal associations of the ammonoid Balatonites balatonicus Zone and the foraminiferal Pilammina densa Zone. This is the first report based on ammonoid and foraminiferal faunas, which allowed initial biostratigraphic subdivision of the Middle Anisian strata from the whole Eastern Serbia region. [ABSTRACT FROM AUTHOR]

This paper presents a detailed description of the lithostratigraphy of mostly contouritic deposits from the Piedra Buena Terrace (PBT), collected at water depth of 2–2.5 km. It is based upon a multi-proxy investigation of five gravity cores, including visual description and scanning, grain size distributions, microfossils and sand fraction study, supported by the analysis of high-resolution sub-bottom profiles. Two older seismic units were identified in addition to those previously described in the area. The defined lithostratigraphic units were correlated to the upper seismic units, while the age of the younger units was confirmed using AMS-14C dating. In terms of the sedimentary facies, the dark quartz-glauconitic sands, which seem to be a fingerprint of the Piedra Buena Terrace, were investigated by applying the X-ray diffraction and performing grain SEM - SE images. The sandy facies correspond to sea-level low-stands during cold glacials (MIS 2 and MIS 4), when glauconite and terrigenous material were transported from the emerged shelf down and along the Patagonian continental slope by vigorous bottom currents. The latter is confirmed by an occurrence of parts of bi-gradational sequences reported from the grain-size distributions in lithostratigraphic units 2 and 4. Units 1 and 3, represented by mostly hemipelagic calcareous ooze, were formed during warm high sea-level stages (MIS 1 and 3). Unlike Unit 1, Unit 3 also demonstrates clear contourite features, similar to Units 2 and 4. They include common bioturbation, occurrence of mottles, lenses, irregular thin layers of sand, erosional boundaries and hiatuses between and within the units, good sorting of fine sands, and microfossil reworking. Together with our previous data from canyons on the Perito Moreno Terrace and the Ameghino segment, supported by available publications from the PBT and Mar del Plata areas, this study demonstrates that the Patagonian Continental Margin could be used as a natural laboratory to investigate and better understand contourite systems. • Massive quartz-glauconite sands discovered on the PBT. • Detailed litho- and chronostratigraphy provided for ∼70 ka. • Contourite sediments identified between ∼70 and ∼14ka. • More developped glauconitization phase during glacials. • New seismic units and unconformities identified in the PBT. [ABSTRACT FROM AUTHOR]

Human-induced carbon emissions are altering the modern climate, with severe repercussions on ecosystems. Among others, anthropogenic pressure is causing deoxygenation of the bottom water, with the widespread establishment of hypoxic zones in several Mediterranean areas. The geological archives allow investigating past deoxygenation dynamics (sapropel events) and their impact on marine ecosystems. Here, we compare the causes and the evolution of deoxygenation dynamics which occurred during two different time periods (Messinian and Holocene) in different paleoceanographic settings based on their micropaleontological content. The Messinian sapropel events are the result of increased export productivity during a relatively cold and arid context, triggering bottom anoxic conditions. The Holocene sapropel formed in response to weakening/stopping of the thermohaline circulation due to increasing temperature and freshwater input. Our results suggest that the deoxygenation dynamics in the Mediterranean in the near future will not follow the trend characteristic of the Holocene deep-sea sapropel because of the predicted drying trend. Differently, the paleoceanographic setting triggering the Messinian shallow-sea sapropels is comparable with the modern situation in different Mediterranean areas, where human-induced eutrophication is promoting deoxygenation. Based on these results, we suggest that the patchy deoxygenation trend in the Mediterranean Sea caused by climate warming may lead to a drastic change in the ecosystem services which would likely impact human activities.

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The results of a comprehensive microfaunistic study of the Ogarkovo Upper Jurassic–Lower Cretaceous reference section on the Unzha River (Kostroma oblast) are presented. The Lower Kimmeridgian, the Upper Volgian and the Ryazanian stages contained variably mineralized three-dimensional remains of radiolarians. The radiolarian genera Protovallupus and Vallupus are recorded for the first time from the Russian Platform. Representative foraminiferal and nannoplankton assemblages and isolated ostracod shells Schuleridea triebeli were identified in the Lower Kimmeridgian. The foraminiferal-based Lenticulina kuznetsovae–Epistomina praetatariensis Zone and were established in the Lower Kimmeridgian. The occurrences of the Mniovniki Formation are for the first time recorded in the Kostroma Zavolzhye region. The age of the Ogarkovo Unit (Ryazanian Tzikwinianus Zone—Lower Valanginian Undulatoplicatilis Zone) is updated. [ABSTRACT FROM AUTHOR]

Research subject. The choice of the marker and the GSSP (Global Boundary Stratotype Section and Point) of the base of the Serpukhovian is currently one of the most urgent tasks of international stratigraphy. The first appearance datum (FAD) of the conodont Lochriea ziegleri in the lineage Lochriea nodosa – Lochriea ziegleri is proposed as a global marker for the lower boundary of the Serpukhovian Stage of the International Stratigraphic Scale. Foraminifers are widely used for the subdivision of the Carboniferous deposits and can serve as auxiliary markers. Materials and methods. In this paper, the stratigraphic distribution of the foraminiferal marker species Janischewskina delicatа, Neoarchaediscus postrugosus, Eolasiodiscus donbassicus, Monotaxinoides gracilis, Monotaxinoides subplanus is discussed. These species are used to define the lower boundary of the Serpukhovian in the Urals and in the East European Platform. Results. Data on the first descriptions of their holotypes are summarized. The distributions of these species in the sections of the western slope of the Urals (Kugarchi, Muradymovo, Ladeinaya), the eastern slope of the South Urals (“Verkhnyaya” Kardailovka, Bolshoi Kizil, Khudolaz), the Serpukhovian type sections of the Moscow Syneclise and the boreholes of the southeast of the East European Platform are compared. The published ranges of the marker species in the sections of Western Europe (Spain, France, and northern England), Morocco, Kazakhstan, and China, including the Naqing section are reviewed. Conclusion. In the shallow-water coral-brachiopod and bioherm facies of the Ural sections, two or three markers can be found simultaneously. In these sections, it is possible to unambiguously determine the lower boundary of the Serpukhovian. However, here, conodonts and ammonoids were not found. Deep-water cephalopod facies containing conodonts are not favorable for foraminifers. In sections where both conodonts and foraminifera are simultaneously encountered, the appearance of foraminiferal marker taxa and conodonts rarely coincide; however, the divergence is small. Regarding the marker taxa under study, their appearance has not been established in sediments older than those dated as the Serpukhovian.

Abstract A new early Visean coral assemblage has been recorded from turbidite facies in the southern part of the Azrou-Khenifra Basin, northwest of Khenifra, central Morocco. The newly discovered Ba Moussa West (BMW) coral fauna includes Siphonophyllia khenifrense sp. nov., Sychnoelasma urbanowitschi, Cravenia lamellata, Cravenia tela, Cravenia rhytoides, Turnacipora megastoma and Pleurosiphonella crustosa. The early Visean age of the coral assemblage is supported by foraminiferal and conodont data, with the recognition of the basal Visean MFZ9 Zone. This confirms that the first transgression in the Azrou-Khenifra Basin was during the earliest Visean. The allochthonous coral assemblage was recovered from coarse-grained proximal limestone debris flow and turbidite beds within a fault-bounded unit, lying to the west of a thrust syncline containing upper Visean limestones. No evidence exists of the former early Visean shallow-water platform from which the corals were derived. All other in situ platform carbonate rocks around the southern margin of the Azrou-Khenifra Basin are probably of late Visean (Asbian–Brigantian) age. The early Visean Ba Moussa West coral fauna can be compared with that at Tafilalt in eastern Morocco, as well as in other Saharian basins of Algeria. Many of the genera and species in the Ba Moussa West assemblage are identical to those in NW Europe, with which it must have had marine connections. The new rugose species described, Siphonophyllia khenifrense, is probably endemic to North Africa. Its ecological niche in NW Europe was occupied by S. cylindrica or S. aff. garwoodi.

The impacts on ostracods and foraminifers caused by three Late Quaternary ashfalls of different intensities and recovered in the ANTA02-NW2 core sediments (Drygalski Basin, western Ross Sea) were analysed for the first time. Albeit with different timing, both associations demonstrated similar response patterns associated with the deposition of material from volcanic eruptions. In particular, based on the palaeontological evidence, it was possible to divide the cores into four intervals/phases recording the evolution of the ecosystem before and after the deposition events: (1) Pre-extinction phase (high abundance and high diversity values). (2) Extinction phase, characterised by the complete disappearance of ostracod fauna; the foraminiferal assemblage, although not entirely absent, records extremely low values of abundance and diversity (survivor assemblage). (3) Recovery phase (increasing abundance and diversity values), characterised by the recolonisation of some opportunistic taxa; species such as Australicythere devexa and Australicythere polylyca dominate the ostracod assemblage. (4) Post-extinction phase (high abundance and high diversity values), with the return to an environmental equilibrium characterised by the colonisation of specialised taxa such as Argilloecia sp., Cytheropteron sp., Echinocythereis sp., and Hemicytherura spp. Our results may aid in the understanding of how communities (i.e., ostracods and foraminifers) recovered after the impact of direct deposits of volcanic ash into ocean waters. The mechanisms by which disappearance and/or mortality was induced are still not clear. The release of toxic metals during the reaction of the volcanic ash with seawater, the resulting chemical alteration in the seawater, and the change in pH, together with the possible suppression of planktonic organisms, may have caused the two main extinction phases recorded by the ANTA02-NW2 core sediments.

We combined biostratigraphical analyses, archaeological surveys, and Glacial Isostatic Adjustment (GIA) models to provide new insights into the relative sea-level evolution in the northeastern Aegean Sea (eastern Mediterranean). In this area, characterized by a very complex tectonic pattern, we produced a new typology of sea-level index point, based on the foraminiferal associations found in transgressive marine facies. Our results agree with the sea-level history previously produced in this region, therefore confirming the validity of this new type of index point. The expanded dataset presented in this paper further demonstrates a continuous Holocene RSL rise in this portion of the Aegean Sea. Comparing the new RSL record with the available geophysical predictions of sea-level evolution indicates that the crustal subsidence of the Samothraki Plateau and the North Aegean Trough played a major role in controlling millennial-scale sea-level evolution in the area. This major subsidence rate needs to be taken into account in the preparation of local future scenarios of sea-level rise in the coming decades. [ABSTRACT FROM AUTHOR]

In this paper, we present the detailed microfacies study and geochemical characteristics of carbonate exotics (olistoliths) associated with the Eocene Disang group of Assam–Arakan Basin, Northeast India to deduct their relative age, and depositional environment. The studied carbonate rocks contain diverse fauna with the dominance of foraminiferal assemblages (planktonic and benthic). The well-preserved planktonic foraminifera, especially Globotruncana spp. and Heterohelix spp. are recorded in carbonates and age has been assigned as late Cretaceous (Maastrichtian in age). Rare earth element (REE) contents (~ 56 ppm average value) in these carbonates are high compared with the average value of typical marine carbonate (~ 28 ppm). The Post-Archean Australian Shale (PAAS)-normalized REE patterns of these carbonates exhibit seawater-like REE patterns with light rare earth elements (LREE) depletion and relatively heavy rare earth elements (HREE) enrichment with negative Ce anomalies and positive Eu anomalies. The geochemical data along with microfacies suggest that the investigated carbonate rocks might have been formed in low energy environments deposited in neritic to bathyal palaeoenvironment during Campanian–Maastrichtian age. Our study also confirmed that the investigated Disang group carbonates are similar to the adjoining carbonates exposed in the ophiolitic mélange zone of Manipur ophiolites, NE India. It is likely that the carbonate rocks were influenced by diagenetic activities at different tectonic processes during the evolution of MOC and later emplaced with the Disang group flysch-like sediments during subduction and obduction processes of the Indian plate and Myanmar plate collision. [ABSTRACT FROM AUTHOR]

This paper reviews the foraminiferal biostratigraphy of the Devonian–Carboniferous (D–C) boundary beds in Russia and Western Kazakhstan. The regional records of the zonal successions of Russia are summarised from sections and boreholes of the Volga-Urals Subregion of the East European Platform (Syzran no. 401 Borehole, Melekesskaya no.1 Borehole); Timan-Pechora Province of the East European Platform (Kamenka Section); South Urals (Sikaza, Zigan, Ryauzyak and Dzerzhinka sections); Middle Urals (Pershino Section); and West Siberia, Vagai-Ishim Basin (Borehole no. 1 Kurgan-Uspenskaya), and the zonal successions of Western Kazakhstan are summarised from the Mugodzhary Mountains. Three foraminiferal biozones can be defined in the interval comprising the latest Devonian and earliest Carboniferous: Quasiendothyra kobeitusana Zone, the Tournayellina pseudobeata – remnant Quasiendothyra Zone, and the Earlandia minima Zone. The D–C boundary interval is situated within the Tournayellina pseudobeata–remnant Quasiendothyra Zone. A correlation with the ammonoid and conodont zonations is proposed, which is useful for correlating deep-water and shallow-water successions. [ABSTRACT FROM AUTHOR]

The continuous and well-accessible Devonian-Carboniferous boundary successions of the Czech Republic are part of the Brunovistulian Unit, which belongs to the Variscan Rhenohercynian Zone of the Bohemian Massif. The well-studied sections, with almost continuous carbonate sedimentation, crop out in the Moravian Karst area and are characterised by carbonate turbidites (Lesní lom) and hemipelagic successions (Křtiny). In the Lesní lom quarry, a complete succession of conodont zones of the Devonian-Carboniferous boundary interval (Upper expansa, praesulcata, costatus-kockeli, kockeli, sulcata/kuehni, bransoni, duplicata zones) was documented in calciturbidites and can be correlated with coeval foraminiferal zones (Quasiendothyra kobeitusana, Quasiendothyra konensis and Tournayellina pseudobeata zones). The Hangenberg Crisis and its three phases can be well recognised both with lithological, biostratigraphical and geochemical approaches in the Lesní lom section. At Křtiny, the nodular limestones yielded conodonts of the Devonian-Carboniferous boundary interval, but missing protognathodid fauna hampered identification of the kockeli Zone. A stratigraphic gap covering the basal part of the sulcata/kuehni Zone or strong condensation can be inferred from the occurrence of the transitional morphotype Si. sulcata-bransoni at the base of this zone. The tested "Montpellier criterion" for the Devonian-Carboniferous boundary redefinition can be used only in the Lesní lom section, where the first Protognathodus kockeli occurs above the regressive Hangenberg Sandstone Event deposits. [ABSTRACT FROM AUTHOR]

This paper presents the first detailed biostratigraphic investigation of deposits cropping out in stream Sumijevac near Koceljeva (western Serbia). The most important fossil communities and their significance are presented. New biostratigraphic results have been achieved by the study of calcareous nannoplankton, foraminifera and mollusks fauna which clearly indicate the presence of the lower Badenian zone (Lagenid Zone), and defines preciously time of the marine transgression in this area. Further, the revised age of the sedimentary deposits presented here provides the necessary background information for future research of the Badenian sediments of Serbia and neighbouring regions.

The fauna of benthic foraminifers from the northern Laptev Sea has been analyzed to identify the relationship between the distribution of benthic foraminifers and environmental conditions in the eastern and western parts of the sea. The abundance of benthic foraminifer tests in the Laptev Sea is universally low, no more than 3–9 ind./g. Greater foraminifer abundances were found in the west, on the shelf of the Vilkitsky Strait. Foraminifers with agglutinated tests were dominant, 77–100%. In the east, the assemblages consisted almost entirely of agglutinated tests (90–100%). Calcareous Melonis barleeanus was common, up to 10–15%, on the shelf and the continental slope in the western part of the sea. Small specimens of the polar planktic species Neogloboquadrina pachyderma sin occurred. In one sample at an abyssal water depth of 2996 m, the abundance of its tests increased to 302 ind./g; the assemblage was composed predominantly of N. pachyderma sin., both small (juvenile) and large (adult) individuals with good preservation. The massive presence of the polar species N. pachyderma sin. at an abyssal depth in the eastern region indicates the dominant influence of Arctic waters there. [ABSTRACT FROM AUTHOR]

A late Viséan fossiliferous limestone block from the Kirchbach Formation (Mississippian) in the Carnic Alps (southern Austria) has been studied for its palaeontological and petrographic characteristics. The limestone block contains abundant fossils and is composed of different microfacies including bioclastic floatstone, coral bafflestone, bryozoan bindstone, bryozoan wacketo grainstone, as well as bioclastic mudto wackestone. The described fauna of bryozoans and foraminifers identify the age of the block as early Serpukhovian (Tarusian), and indicate deposition in a shallow shelf environment with high to moderate energy levels, moderate to high sedimentation rates and flexible to hard substrates. The limestone block, like the exotic limestone clasts of the carbonate conglomerates of the Kirchbach Formation, were transported into deeper marine environments by gravitational sedimentary processes from a shallow marine carbonate shelf that was developed along the northern margin of the Hochwipfel flysch basin. [ABSTRACT FROM AUTHOR]

In this study of Mississippian rocks in Ireland, it is now recognized, based on faunal evidence, that several upper Viséan limestone formations which were previously excluded from the Serpukhovian now belong, in part, to the lower two substages of the Serpukhovian. A reassessment of previous foraminiferal determinations, together with new foraminiferal data, has confirmed that rocks equivalent to the Tarusian and Steshevian substages are present in several sections. In the Slievenaglasha Formation and Magowna Formation (County Clare) and Deer Park Formation (County Meath), Tarusian and Steshevian foraminiferal assemblages are thus recorded. In the Clogrenan Formation (County Carlow), Carganamuck Limestone Formation (County Armagh) and Rockdale Limestone Formation (County Tyrone), Tarusian foraminiferal assemblages are recorded in the upper beds of thick limestone successions. Key foraminiferal and algal taxa characterize each assemblage, which have been correlated with equivalent Serpukhovian strata in the north of England and Scotland. A three‐stage evolution is recognized in archaediscid foraminifers: from Neoarchaediscus gregorii, followed by Neoarchaediscus postrugosus form 1, and N. postrugosus form 2, with Neoarchaediscus postrugosus form 1 used to define the base of the Serpukhovian. The recognition of Tarusian and Steshevian foraminiferal assemblages implies that areas of shallow‐water platform carbonate sedimentation in Ireland during the upper Viséan (Brigantian) persisted into the Early Serpukhovian. [ABSTRACT FROM AUTHOR]

Microfossils of the upper Bajocian Garantiana garantiana Zone of the Kyafar River (a tributary of the Bolshoi Zelenchuk River, Karachay-Cherkess Republic) are studied. The zone is represented by dark gray claystone-like clay series with sporadically scattered nodules, often forming interlayers, and is recognized in the upper subformation of the Djangura Formation. The taxonomic composition and distribution in the section of foraminifers, ostracods, dinoflagellate cysts, and miospores are studied. The range of foraminiferal and dinocyst biostratigraphic units and their correlation with the ammonite scale are established. On the basis of benthic foraminifera, these are Beds with Ophthalmidium caucasicum, corresponding to most of the Garantiana Zone, and Beds with Sublamarckella terquemi, corresponding to the upper part of the Garantiana Zone and the lower part of the Parkinsoni Zone. The Beds with Globuligerina dagestanica, recognized on the basis of planktonic foraminifera, are compared with the entire studied interval from the Garantiana Zone to the bottom of the lower Bathonian inclusive. The Beds with Meiourogonyaulax valensii and Rhynchodiniopsis? regalis (dinocysts) are considered equivalent to the entire range of the Garantiana Zone to the lower part of the Parkinsoni Zone inclusive. The key fossils are illustrated. [ABSTRACT FROM AUTHOR]

To reconstruct the climatic and paleoceanographic variability offshore Northeast Greenland during the last ~10 ka with multidecadal resolution, sediment core PS93/025 from the outermost North-East Greenland continental shelf (80.5°N) was studied by a variety of micropaleontological, sedimentological and isotopic methods. High foraminiferal fluxes, together with high proportions of ice-rafted debris and high Ca/Fe ratios, indicate a maximum in bioproductivity until ~8 ka related to a low sea-ice coverage. Sortable silt values, planktic foraminifer associations, and stable isotope data of planktic and benthic foraminifers suggest a strong westward advection of relatively warm Atlantic Water by the Return Atlantic Current during this time, with a noticeable bottom current activity. This advection may have been facilitated by a greater water depth at our site, resulting from postglacial isostatic depression. For the following mid-Holocene interval (ca. 8–5 ka), isotope data, lower foraminiferal fluxes and a shift in grain size maxima point to a lasting but successively decreasing Atlantic Water inflow, a weakening productivity, and a growing sea-ice coverage which is also revealed by the PIIIIP25 index. A final stage in the environmental development was reached at ~5 ka with the establishment of pre-industrial conditions. Low Ca/Fe ratios, low foraminiferal fluxes, low sortable silt values and the sea-ice indicating PIIIIP25 index point to a limited productivity and a weak Atlantic Water inflow by the Return Atlantic Current to our research area, as well as a higher and/or seasonally more extended sea-ice coverage during the Late Holocene. Two intervals with somewhat enhanced Atlantic Water advection around 2.0 and 1.0 ka are indicated by slightly increased foraminiferal fluxes and the reoccurrence of subpolar foraminifers. These intervals may correlate with the Roman Warm Period and the Medieval Climate Anomaly, as defined in the North Atlantic region. [ABSTRACT FROM AUTHOR]

Lithofacies analyses and datings using calcareous nannofossils, proved to be an excellent opportunity to understand the palaeoenvironmental evolution of the area of the Tuscan coast, washed up by the Ligurian Sea. A multidisciplinary approach, through lithological and micropaleontological data, collected from fifteen boreholes and one outcrop, permitted the characterization of ten stratigraphic units in the subsurface of the Livorno area. The correlations of these units depicted a stratigraphic architecture chronologically constrained. This study detected early Pliocene (Zanclean) and early Pleistocene (Gelasian) marine deposits, referable to the outer neritic zone that were dated to the calcareous nannofossil biozones MNN13, MNN14-15 and MNN18. In addition, early Pleistocene (Calabrian) marine deposits, dated to the calcareous nannofossil biozones MNN19b, MNN19d, MNN19e, which may be attributed to different bathymetric depths on the basis of benthic foraminifers and ostracods, highlighted sea level changes. Finally, the areal distribution and the stratigraphic architecture of these units permitted the recognition and the better constraining of the sedimentary dynamics impacted by major eustatic and tectonic changes.

The paper contains multidisciplinary data on the lithology and palaeontology of the Devonian–Carboniferous boundary beds in the shallow-water facies in the Bolshaya Usa River section (Vorkuta Uplift). A recent discussion on the position and marker of the Devonian–Carboniferous GSSP shows that this study is highly relevant. In the Bolshaya Usa River section, the boundary almost coincides with the boundary of the Bakhromchataya Fm. and Vazhkhanovey Fm. The upper part of the Famennian (upper part of the Bakhromchataya Fm.), which is mainly composed of microbial, algal, and bioclastic carbonates (wackestone), contains poor conodont and foraminifer associations. Prioniodinida dominates the conodont associations. Foraminifers are mainly represented by unilocular forms accompanied by the rare Eoendothyra and Quasiendothyra. The lower part of the Tournaisian (basal beds of the Vazhkhanovey Fm.) is composed of clastic carbonates containing numerous brachiopod shells (Spinocarinifera). Conodont associations are represented by Prioniodinida of wide stratigraphic range, as well as by Pseudopolygnathus primus Branson et Mehl and Patrognathus crassus Kononova et Migdisova. Foraminifers are represented by just unilocular forms, namely: Parathuraminites, Parathuramina, Bisphaera, Vicinisphaera, and Earlandia. The position of the Devonian-Carboniferous boundary in the study section is defined by the first occurrence of conodonts Patrognathus crassus, Pseudopolygnathus cf. primus and foraminifers Earlandia cf. minima and E. elegans. These taxa can be considered as markers of the boundary in shallow-water facies of the carbonate platform.

Detail results of microfaunal, sedimentological and geochemical investigations are documented from a newly discovered section of the Permian–Triassic boundary (PTB) interval in the area of the town of Valjevo (northwestern Serbia). The presence of various and abundant microfossils (conodonts, foraminifers, and ostracodes) found in the Upper Permian “Bituminous limestone” Formation enabled a determination of the Changhsingian Hindeodus praeparvus conodont Zone. This paper is the first report of latest Permian strata from the region, as well as from all of Serbia, where the PTB interval sediments have been part of a complex/integrated study by means of biostratigraphy and geochemistry.

The Cenozoic marine deposits (two formations) developed in the eastern part of the Opukha–Pekulney Depression of the Koryak Upland are described. Until recently, there was scarce information about them. The lower (Retyrveem) formation is composed of dark conglomerates and sandstones with a large number of carbonate nodules and representative assemblages of bivalve and gastropod mollusks (more than 400 tests and imprints were studied) and Early Eocene benthic foraminifers. Two subformations and six units were distinguished in the formation. The upper (Morzhovaya) formation is composed of light loose gravestones and sandstones, including fragments of Early Miocene mollusks and foraminifers. The study of faunal assemblages makes it possible to correlate these formations with stratigraphic units of adjacent areas and to reveal hiatuses in the section covering most of the Paleocene sequence, on one hand, and the Upper Eocene and Oligocene, on the other hand. The Retyrveem Formation encloses warm-water molluscan assemblages, the appearance of which in the northern boreal latitudes is supposed to be related to the Early Eocene global warming. Images of the characteristic molluscan remains are given for the first time. [ABSTRACT FROM AUTHOR]