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EN
The Upper Cretaceous succession (Coniacian to lowermost Maastrichtian, with focus on the Campanian) at Petrich, Central Srednogorie Zone in Bulgaria, is described and calibrated stratigraphically based on nannofossils, dinoflagellate cysts and inoceramids. The following standard nannofossil zones and subzones are identified: UC10-UC11ab (middle to upper Coniacian), UC11c-UC12-UC13 (uppermost Coniacian to Santonian), UC14a (lowermost Campanian), UC14bTP-UC15cTP (lower Campanian to ‘middle’ Campanian), UC15dTP-UC15eTP (upper Campanian), UC16aTP (of Thibault et al. 2016; upper part of the upper Campanian), and UC16b (Campanian-Maastrichtian boundary). The base of the Campanian is defined by the FO of Broinsonia parca parca (Stradner) Bukry, 1969 and Calculites obscurus (Deflandre) Prins and Sissingh in Sissingh, 1977 (a morphotype with a wide central longitudinal suture). The Areoligera coronata dinoflagellate cyst Zone (upper lower Campanian to upper upper Campanian) is identified, corresponding to the UC14bTP-UC16aTP nannofossil subzones. The inoceramid assemblage indicates the ‘Inoceramus’ azerbaydjanensis-‘Inoceramus’ vorhelmensis Zone, correlated within the interval of nannofossil subzones UC15dTP-UC15eTP. The composition of the dinoflagellate cyst assemblages and palynofacies pattern suggest normal marine, oxic conditions and low nutrient availability within a distal shelf to open marine depositional environment during the Campanian.
EN
Among the rich dinoflagellate cyst assemblages recovered from the upper Campanian-lowermost Maastrichtian succession of the Middle Vistula River section (central Poland), four taxa (Callaiosphaeridium bicoronatum, Odontochitina dilatata, Oligosphaeridium araneum and Samlandia paucitabulata) have been described as new. An analysis of the distribution of particular dinoflagellate cyst taxa enabled the development of a highly resolved biostratigraphic framework, calibrated against other biozonal schemes (based, among others, on inoceramid bivalves, ammonites and belemnites), formerly established for the succession. A comparison of the Middle Vistula River record with the dinoflagellate cyst ranges documented in other European successions enabled correlations with selected sections in Belgium, the Netherlands, southern Germany and northern Italy, and with the Campanian/Maastrichtian boundary stratotype section in Tercis les Bains, southwest France. A palaeoecological analysis of the dino- flagellate cyst assemblages and of other components of phytoplankton communities revealed a well-defined trend in sea-level fluctuations (likely of eustatic origin), and palaeoclimatic changes probably related to the latest Cretaceous cooling episode, as observed elsewhere.
EN
The Coniacian quartz sandstones (Żerkowice Member, Rakowice Wielkie Formation) that crop out at quarries near Czaple-Nowa Wieś Grodziska (North Sudetic Synclinorium) contain a low-diversity assemblage of trace fossils: Gyrochorte isp., Ophiomorpha nodosa Lundgren, 1891, Ophiomorpha isp., Phycodes cf. curvipalmatum (Pollard, 1981), ?Phycodes isp., Planolites cf. beverleyensis (Billings, 1862), Thalassinoides paradoxicus Woodward, 1830 and ?Thalassinoides isp. Moreover, interesting compound burrow systems, here referred to as Thalassinoides-Phycodes cf. palmatus and ?Thalassinoides-Phycodes, were recognised at the Czaple Quarry. Additionally, ?Gyrochorte isp., Phycodes cf. flabellum (Miller and Dyer, 1878) and ?Treptichnus isp. were encountered at correlative levels in the Rakowice Małe Quarry. Some of these ichnotaxa have not been recorded previously from Coniacian sandstones of the Żerkowice Member. Additionally, in slabs of these sandstones, the gastropod Nerinea bicincta Bronn, 1836 and the bivalve Lima haidingeri Zittel, 1866 were found. These interesting finds, in particular the gastropods, were already noted from the study area in the first half of the twentieth century by Scupin (1912–1913). Ethologically, the trace fossil assemblage is represented by domichnia or domichnia/fodinichnia (Ophiomorpha, Thalassinoides), fodinichnia (Phycodes) and pascichnia (Gyrochorte, Planolites). The compound burrow systems (Thalassinoides-Phycodes) are interpreted as dwelling/feeding structures. The possible tracemakers are crustaceans (Ophiomorpha, Thalassinoides) or worm-like animals (annelids and other) (Planolites, ?Phycodes, Gyrochorte and ?Treptichnus). The assemblage of trace fossils is characteristic of the Skolithos ichnofacies and Cruziana ichnofacies, typical of shallow-marine settings. Ichnological studies, as well as the presence of accompanying fossils (bivalves, gastropods), confirm the palaeoenvironmental reconstruction of the Żerkowice Member sandstones by Leszczyński (2010). That author interpreted the Coniacian sandstones as bar and storm deposits laid down in a shallow epicontinental sea (mainly the foreshore-upper shoreface; up to the middle shoreface) under normal oxygenation and salinity, in soft substrate, above fair-weather wave base. The deposition of the Żerkowice Member sandstones is linked to a regression that started after uplift of the southeastern part of the North Sudetic Synclinorium.
EN
The lower (but not lowermost) part of the Upper Cretaceous Anaipadi Formation of the Trichinopoly Group in the area between Kulatur, Saradamangalam and Anaipadi, in the south-western part of the Cauvery Basin in southeast India yielded rich inoceramid and ammonite faunas. The ammonites: Mesopuzosia gaudama (Forbes, 1846), Damesites sugata (Forbes, 1846), Onitschoceras sp., Kossmaticeras (Kossmaticeras) theobald ianum (Stoliczka, 1865), Lewesiceras jimboi (Kossmat, 1898), Placenticeras kaffrarium Etheridge, 1904, and Pseudoxybeloceras (Schlueterella) sp., are characteristic of the Kossmaticeras theobaldianum Zone. The absence of Peroniceras (P.) dravidicum (Kossmat, 1895) indicates the presence of only lower part of this zone, referred to the nominative Kossmaticeras theobaldianum Subzone at the localities studied. The inoceramids present are Tethyoceramus madagascariensis (Heinz, 1933) and Cremnoceramus deformis erectus (Meek, 1877), recorded for the first time from the region. The latter dates the studied interval as early early Coniacian, and allows, for the first time, direct chronostratigraphic dating of the Tethyoceramus madagascariensis Zone, and consequently also of the Kossmaticeras theobaldianum Subzone. As inoceramids occur in the middle part of the ammonite-rich interval, the Kossmaticeras theobaldianum Subzone may be as old as latest Turonian and not younger than early early Coniacian. The base of the Coniacian lies in the lower, but not lowermost part of the Anaipadi Formation. Both inoceramids and ammonites represent taxa known from Madagascar and South Africa.
EN
The upper lower Cenomanian through middle Santonian (Upper Cretaceous) of the Boquillas Formation in the Big Bend Region of Trans-Pecos Texas consists of a marine carbonate succession deposited at the southern end of the Western Interior Seaway. The Boquillas Formation, subdivided into the lower, c. 78 m thick limestone-shale Ernst Member, and the upper, c. 132 m thick limestone/chalk/marl San Vicente Member, was deposited in a shallow shelf open marine environment at the junction between the Western Interior Seaway and the western margins of the Tethys Basin. Biogeographically, the area was closely tied with the southern Western Interior Seaway. The richly fossiliferous upper Turonian, Coniacian and lower Santonian parts of the Boquillas Formation are particularly promising for multistratigraphic studies.
EN
For a long time, outcrops at Potelych, Nahoryany and Lviv in western Ukraine have been of special interestfor Campanian andMaastrichtian (Upper Cretaceous) palaeontology and biostratigraphy. An overview of studies devoted to these classic sites is presented, including an early account of the locality of Nahoryany in a Polish newspaper, dated 1843. The biostratigraphic position ofthese successions is reviewed, based on recent progress in studies of inoceramid bivalves and ammonites. The succession at Potelych, from where a unique land flora was described at the beginning of the 20th century, represents the upper Campanian “Ino- ceramus” costaecus Zone. The Nahoryany opoka, the source of rich fossil collections that were sent to many European museums in the 19th century, belongs to the lower Maastrichtian Endo- costea typica and Trochoceramus radiosus zones. The so-called Lviv marls correspond to the lower upper Maastrichtian Spyridocera- mus tegulatus Zone. The giant scaphitid ammonites Hoploscaphites quadrispinosus and Acanthoscaphites tridens s. str from Potelych and Nahoryany corroborate the inoceramid-based dating of these successions.
EN
The biostratigraphic importance, current zonations, and potential for the recognition of the standard chronostratigraphic boundaries of five palaeontological groups (benthic foraminifers, ammonites, belemnites, inoceramid bivalves and echinoids), critical for the stratigraphy of the Santonian through Maastrichtian (Upper Cretaceous) of extra-Carpathian Poland, are presented and discussed. The summary is based on recent studies in selected sections of southern Poland (Nida Synclinorium; Puławy Trough including the Middle Vistula River composite section; and Mielnik and Kornica sections of south-eastern Mazury-Podlasie Homocline) and of western Ukraine (Dubivtsi). The new zonation based on benthic forams is presented for the entire interval studied. Zonations for ammonites, belemnites and inoceramid bivalves are compiled. All stage boundaries, as currently defined or understood, may easily be constrained or precisely located with the groups discussed: the base of the Santonian with the First Occurrence (FO) of the inoceramid Cladoceramus undulatoplicatus; the base of the Campanian with the Last Occurrence (LO) of the crinoid Marsupites testudinarius and approximated by the range of the foraminifer Stensioeina pommerana; and the base of the Maastrichtian approximated by the FO of the inoceramid bivalve Endocostea typica and the FO of the belemnite Belemnella vistulensis. The positions of substage boundaries, as currently understood, are constrained in terms of the groups discussed.
EN
Dynamic evolution of the Campanian and Maastrichtian (Upper Cretaceous) of the Miechów Synclinorium is presented. Through chronostratigraphic analysis, the geometry of the Campanian and Maastrichtian of the area is interpreted, while microfacies analysis allowed determination of some of the paleoenvironmental parameters (rate of sedimentation, bottom condition and terrigenous input). The chronostratigraphy is based on inoceramid biostratigraphy. Nine inoceramid zones are recognized: Sphenoceramus patootensiformis, Sphaeroceramus sarumensis-Cataceramus dariensis and ‘Inoceramus’ azerbaydjanensis-‘Inoceramus’ vorhelmensis, ‘Inoceramus’ tenuilineatus, Sphaeroceramus pertenuiformis, ‘Inoceramus’ inkermanensis and ‘Inoceramus’ costaecus-‘Inoceramus’ redbirdensis (Campanian); Endocostea typica and Trochoceramus radiosus (Maastrichtian). Five unconformities (isochronous in the study area) represented by horizons of slower sedimentation rate, were recognized. They correlate with eustatic sea-level changes, well recorded in European successions (Jarvis et al. 2002, 2006; Niebuhr et al. 2011). Unconformity horizons allow six alloformations to be distinguished. The thickness of particular chronostratigraphic units within the Campanian and Lower Maastrichtian increases progressively toward the axis of the Danish-Polish Trough, which indicates that the inversion of the trough could not have started before the Late Maastrichtian.
EN
Biostratigraphic correlations of inoceramid bivalves between the North Pacific and Euramerican provinces have been difficult because the inoceramid biostratigraphy of the Japanese strata has been based on endemic species of the northwest Pacific. In this study, carbon stable isotope fluctuations of terrestrial organic matter are assembled for the Upper Cretaceous Yezo Group in the Haboro and Obira areas, Hokkaido, Japan, in order to revise the chronology of the inoceramid biozonation in Japan. The carbon isotope curves are correlated with those of marine carbonates in English and German sections with the aid of age-diagnostic taxa. According to the correlations of the carbon isotope curves, 11 isotope events are recognised in the sections studied. As a result of these correlations, the chronology of the inoceramid biozones of the Northwest Pacific has been considerably revised. The revised inoceramid biozones suggest that the timing of the origination and extinction of the inoceramids in the North Pacific biotic province is different from the stage/substage boundaries defined by inoceramids, as used in Europe and North America.
EN
In Egypt, marine Upper Cenomanian.Turonian strata are well exposed in the Eastern Desert. The southernmost outcrops are located in the central part of Wadi Qena, where the lower Upper Cretaceous is represented by the fossiliferous Galala and Umm Omeiyid formations. From these strata, numerous ammonites have been collected bed-by-bed and 13 taxa have been identified, which are systematically described herein. Four of them (Euomphaloceras costatum, Vascoceras globosum globosum, Thomasites gongilensis and Pseudotissotia nigeriensis) are recorded from Egypt for the first time. The ammonite ranges are used for a biostratigraphic zonation of the lower Upper Cretaceous succession in the northern and central part of Wadi Qena: the Upper Cenomanian.Lower Turonian has been subdivided into five biozones (including a new upper Lower Turonian biozone based on the occurrence of Pseudotissotia nigeriensis), and one biozone has been recognized in the Upper Turonian. Palaeobiogeographically, the ammonite assemblage has a Tethyan character. During the Early Turonian, influences of the Vascoceratid Province were predominant with strong affinities to typical Nigerian faunas. This shows the significance of faunal exchange between Egypt and Central and West Africa via the Trans-Saharan Seaway. Compared to contemporaneous ammonoid faunas from the northern part of the Eastern Desert, Boreal influences are much less obvious in Wadi Qena. Thus, the present study greatly enhances the knowledge of the Late Cretaceous palaeobiogeography and biostratigraphy of Egypt and adjacent areas.
EN
An interesting phenomenon of echinoid accumulation occurring in the Lower Turonian (Mytiloides labiatus Zone) at Glanów village (Miechów Upland) is the main topic of the paper. The bed investigated consists of poorly cemented sandy-marly limestones with thickness of about 30 cm. The accumulation of echinoids is older than that of documented in Wielkanoc which is of middleto-late Turonian age and situated in the same region under study. Apart from a dominant echinoid species Conulus subrotundus Mantell represented by adult and juvenile forms that are dispersed in the bed, the second echinoid species -a regular form Salenocidaris granulosa (Woodward)-has also been noted. Additionally, the skeletal elements of crinoids, ophiuroids, asteroids, as well as bryozoans, annelids, poriferans and shark teeth have also been found in the bed under study. Preliminary observations indicate that the origin of the echinoid accumulation corresponds well with the Conulus bed from the Wielkanoc quarry as a result of luxuriant development of echinoids and complex sedimentological, paleoecological and tectonic factors.
EN
Artificial neural networks (ANNs), the computer software or systems that are able to "learn" on the basis of previously collected input data sets are proposed here as a new useful tool in paleontological modeling. Initially ANNs were designed to imitate the structure and function of natural neural systems such as the human brain. They are commonly used in many natural researches such as physics, geophysics, chemistry, biology, applied ecology etc. Special emphasis is put on the Kohonen self-organizing mapping algorithm, used in unsupervised networks for ordination purposes. The application of ANNs for paleontology is exemplified by study of Late Cretaceous belemnites. The Kohonen networks objectively subdivided the belemnite material] ~ 750 specimens) into consistent groups that could be treated as monospecific. The possibility of transferring these results to the language of classical statistics is also presented. Further development and possibility of use of ANNs in various areas of paleontology, paleobiology and paleoecology is briefly discussed.
EN
During the Late Cretaceous, both Mangyshlak and the Opole area were part of the North European Province, and irregular echinoid faunas during the Turonian and Coniacian in both areas were dominated by holasteroids and spatangoids, in particular by Plesiocorys, Echinocorys and Micraster. Almost 1,000 specimens from both areas have been studied. Taxonomically more varied are the faunas species in 3 genera. One species, Micraster (Micraster) praerogalae, a transitional form between Micraster (Micraster) cortestudinarium(GOLDFUSS) and Micraster (Micraster) rogalae NOWAK, is described as new. Micraster (Micraster) rogalae is markedly diachronous within the North European Province, first appearing in the late Coniacian in Mangyshlak and reaching central and western Europe during the late Early Santonian. A similar pattern is revealed by a large morphotype of Echinocorys ex gr. scutata LESKE. Palaeoecological and actualistic data show the taxa studied to have been shallow infaunal (Catopygus), shallow epifaunal [Conulus (Conulus) subrotundus], deeper infaunal [Micraster (Micraster)], deeper semi-infaunal [Micraster (Gibbaster), Plesiocorys (Sternotaxis) plana], deeper epifaunal [Echinocorys, Plesiocorys (Plesiocorys) placenta], and deeper infaunal (Hemiaster). Echinoid bioevents described originally from the Salzgitter-Salder section (Lower Saxony, Germany) can also be recognised in the Opole area, but not further afield in Mangyshlak.
EN
In the Santonian chalk glacial deposits exposed at Kornica (eastern Poland) an assemblage of echinoderms comprising asteroids, echinoids, ophiuroids, and crinoids (comatulids, roveacrinids, and Bourgueticrinus, Isocrinus, Isselicrinus, Marsupites) is documented. The Santonian age of sediments at Kornica has been determined with foraminifers. Numerous occurrences of the crinoid Marsupites testudinarius, indicate their late Santonian age.
15
Content available remote Olistolit w śródlądowych osadach miocenu rowu Kleszczowa
EN
The paper presents the problem of gravity-induced fossil surface mass movements. Along the margins of the Miocene inland basin formed in the Kleszczów Graben, Upper Cretaceous marls forming its northern wall underwent eboulement. Such fragments of older rocks hosted within the younger marine sediments are known as "olistoliths". However, this term has been applied to up to date to structures known from the marine basin shores. This paper describes such a feature occurring at the margin of a continental freshwater basin. As the genesis and formation mechanisms of both structures are identical, it is proposed to extend the usage of the term "olistolith" to cover the inland occurrences, as well.
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