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The paper presents detailed biostratigraphical division and lithological characteristics of the Turonian-Lower Santonian interval within the compiled Chukhonastovka section. The presence of the Lower Turonian deposits has been ascertained alongside with the unusual structure of the rock interval synchronous to the Lower Santonian “sponge” horizon.

Microfaunal analysis of Cretaceous and Paleogene sediments collected over several decades from Western Siberia has illuminated the diversity, stratigraphic distribution, and paleoecological signifi cance of the rare low trochospiral benthic foraminiferal genus Bagginoides. Here, we describe two new species B. yamalensis n.sp. and B. tibeisalinella n.sp [ABSTRACT FROM AUTHOR]

The lower Cenomanian ammonite Sharpeiceras cf. laticlavium (Sharpe, 1855) and the middle Cenomanian ammonite Calycoceras (Gentoniceras) gentoni (Brongniart, 1822) were found for the first time in the Selbuhra Mountain section in Southwestern Crimea. These finds allow us to complete the biostratigraphic subdivision of the Cenomanian in Southwestern Crimea and to expand our understanding of the distribution of these ammonites. [ABSTRACT FROM AUTHOR]

A Cenomanian ammonite, Calycoceras (Calycoceras) naviculare (Mantell, 1822) (Acanthoceratidae, Ammonoidea) has been found in the well-known section of the Selbukhra Mountain in the vicinity of the village of Nauchnyi in southwestern Crimea. This is the first find of the ammonite in the upper Cenomanian deposits in the Crimea and in Russia. [ABSTRACT FROM AUTHOR]

Ammonites of the subfamily Collignoniceratinae have been found in the Turonian Stage of Western Siberia. These findings have made it possible to substantiate the Collignoniceras woollgari zone in the Middle Turonian of this region, to recognize the ammonite dispersal features in the Arctic region, and to clarify the paleogeography of the Turonian age. Based on the occurrence frequency of Collignoniceras woollgari regulare in the boreholes in the north of Western Siberia, their penetration into the West Siberian basin through the Arctic region from the Western Interior Sea of North America is most likely. Collignoniceratinae has been identified for the first time in the Upper Turonian of the Yangoda River (west of the Yenisei–Khatanga regional trough). [ABSTRACT FROM AUTHOR]

A Turonian ammonite, Kamerunoceras sp. ex gr. turoniense (d'Orb.) has been found for the first time in the southwestern Crimea, in the section of the Aksu-Dere ravine, northward of the village of Kudrino (Kacha River basin). This is the first discovery of representatives of this genus in Russia. [ABSTRACT FROM AUTHOR]

Representatives of the genus Sororistirps, distinguished among the Ventriculites, have been detected in the Santonian – Maastrichtian rocks from the southeast of the Russian Plate. The structures of the skeletons and of the irrigation systems have been considered, the Sororistirps morphogenesis has been traced; the forms characteristic of the Santonian, Campanian and Maastrichtian spongiocomplexes have been determined.

The stratigraphy of the Kerch–Taman region has been refined based on foraminiferal assemblages from the clay pulp of the Semigorsky, Andrusov, and Borukh-Oba mud volcanoes. Comparison with the fauna from the reference section of the Paleogene along the Belaya River (Republic of Adygea) enabled us to reveal deposits of the Middle Eocene (Cherkessk and Kuma formations of the Lutetian and Bartonian stages); Lower Oligocene (Pshekha Formation, Rupelian Stage), confirmed by finds of remains of pteropods; and Middle Miocene (Konkian and Sarmatian stages of the Eastern Paratethys regional scale of the Miocene). Cretaceous deposits (Semigorsky Volcano) are attributed to the Late Campanian–Maastrichtian. [ABSTRACT FROM AUTHOR]

Abiostratigraphic assessment of the benthic foraminiferal record at International Ocean Discovery Program (IODP) Site U1513 in the Mentelle Basin (southeast Indian Ocean, offshore western Australia), yielding a Turonian through Santonian deep-water benthic foraminiferal assemblage is presented. Predominantly calcareous deep-water benthic foraminifera are recovered, whereas agglutinated benthic taxa show a rare occurrence. Epifaunal benthic foraminifera make up ~50% of the total assemblage during the Turonian to Santonian. The most frequently recorded taxa are gavelinellids and gyroidinoids. Adistal, bathyal depositional environment is inferred. Two distinct benthic foraminiferal associations, the Gavelinella berthelini association and the Notoplanulina rakauroana association, were identified in the 160 m-thick succession, and together they yield over 190 taxa. At Site U1513 the occurrence of important benthic foraminiferal markers such as Gavelinella berthelini and the Notoplanulina lineage allows a good correlation with other localities in the southern hemisphere and tentatively with the Pacific Realm. Gavelinella bethelini, which is present from the base of the Turonian succession, shows its last occurrence shortly after the Turonian/Coniacian boundary. Notoplanulina rakauroana is recorded to range from the lower Coniacian through the uppermost Santonian. Throughout the Southern Hemisphere, a similar sequence of benthic foraminiferal bioevents in the Upper Cretaceous can be identified at the Walvis Ridge, in South Africa, Argentina, Southern India, the Kerguelen Plateau, the Great Australian Bight, and in New Zealand. This study aims at contributing to the development of an Upper Cretaceous calcareous benthic foraminiferal zonation applicable to the Southern Hemisphere. [ABSTRACT FROM AUTHOR]

New data on the taxonomic composition and stratigraphic distribution of benthic and planktonic foraminifera in the Campanian–Maastrichtian interval of the Beshkosh section (Southwestern Crimea) are presented. Samples were collected using the "sample-to-sample" method for different types of analysis. Zones and Beds were established on the basis the foraminiferal succession. The Angulogavelinella gracilis LC 18 Zone, Bolivinoides draco LC 21 Zone, Brotzenella praeacuta LC 22 Zone and Beds with Gavelinella sahlstroemi were recognized using benthic foraminifera and Beds with Laeviheterohelix glabrans, Guembelitria cretacea Zone were recognized using planktonic foraminifera. All recognized biostrata are correlated with magnetostratigraphic, palynomorph and macrofauna events. Beds and zones recognized based on benthic foraminifera are correlated with Campanian–Maastrichtian bioevents in sections of the European paleobiogeographic region. Planktonic foraminiferal data are correlated with the International Stratigraphic Scale (Tethys Region) and the regional stratigraphic scheme of Poland. For the first time, 15 species of nine planktonic foraminifera genera and 38 species (25 of which were found for the first time) of 25 benthic foraminifera genera have been identified in the Beshkosh section. [ABSTRACT FROM AUTHOR]

The Upper Cretaceous strata of the Zagros area is named Gurpi Formation. The selected stratigraphic section is attributed to a part of Folded–Thrust belt Zone of the Zagros, located 90 km southeast of Shiraz (SW of Iran) and is affected by the Sarvestan basement Fault within the Interior Fars region. The Gurpi Formation is extended approximately 28 m thick and is mainly formed of marly limestone, shale and argillaceous limestone, The biostratigraphy of the Gurpi Formation was investigated by collecting 121 samples from a selected stratigraphic section. Microscopic investigation represents the presence of 12 genera and 27 species of planktonic foraminifera. The stratigraphic distribution of investigated planktonic foraminifera represents eight biozones. The identified biozones in the Kharameh area from base to the top of Gurpi Formation consist of Helvetoglobotruncana helvetica Total Range Zone, Marginotruncana sigali Partial Range Zone, Dicarinella primitiva Interval Zone, Dicarinella concavata Interval Zone, Dicarinella asymetrica Total Range Zone, Globotruncanita elevata Partial Range Zone, Globotruncana ventricosa Interval Zone, Globotruncana aegyptiaca Total Range Zone. Based on the identified planktonic foraminifera and the described biozones, the age of the Gurpi Formation is assigned from middle Turonian to early Maastrichtian. [ABSTRACT FROM AUTHOR]

This study is conducted on the Northern Borders Province, northernmost Saudi Arabia, mapping a newly identified Wadi Al Khirr transtensional fault zone, based on detailed fieldwork, image interpretation as well as GIS work. The Wadi Al-Khirr fault zone extends from west of Al Uwayqilah to Zahwah. Remote sensing satellite data indicate that it can be projected further to the south toward the central Arabian Shield. About 100 km to the east of the newly proposed fault zone, late Cretaceous Linah Formation is changing its eastern lithofacies within the Widyan basin. The changes in lithofacies represent the results of tense diagenetic alteration (many phases of dolomitization/de-dolomitization), accompanied by silicification and carbonate leaching of the carbonate rocks. This western (Mediterranean) and eastern (Arabian Gulf) lithofacies appear to be laterally equivalent in biostratigraphy as it is evidently having Loftusia sp. in both sides. The lithofacies changes occur 100 km to the east of the Wadi Al Khirr fault zone; therefore, it is likely postdating the Upper Cretaceous sequences and may not be associated tectonically with the east to west lithofacies. The Sirhan–Turayf and Widyan basins' boundary is found in this study to have complicated tectonic setting. Wadi Al Khirr fault zone to the east, and the Makkah-Madinah-Nafud with newly interpreted Sakaka lineaments to the west bound the Ha'il arch, separating the two basins. Moreover, the Ha'il arch is cross-cut and deformed by Ar'Ar arch in the upper northern part of the study area and by reactivation of Najd Faults to the south. [ABSTRACT FROM AUTHOR]

Cretaceous deposits containing pelagic red beds (CORBs - Cretaceous Oceanic Red Beds) are developed in the Ukrainian Carpathians. CORBs have a global distribution, they are sharply depleted in organic matter and their formation is associated with periods of cooling and intensive circulation of cold, oxygen-enriched deep-sea currents that oxidize organic carbon. CORBs in the Ukrainian Carpathians are common in the Upper Cretaceous, while the Lower Cretaceous sediments, especially in the Outer (Flysch) Carpathians, are often enriched in organic matter (in particular the black shales of the Shypot and Spas formations). Such change in sediments enriched and depleted in organic matter may be associated with regular climate changes. In the Inner Carpathians, in the both the Peniny Klippen Belt and the Marmarosh Klippen Zone, CORBs are represented by thick (100-200 m) mostly red-colored marls and shales that make up the Turonian - Maastrichtian Puchov Formation. A fragment of the Puchov Formation of the Turonian age is presented in the Marmarosh Massif. Stratigraphically, the lowest CORBs represented by layers of pink marls are noted in the upper part (Middle-Upper Cenomanian) of the Tysalo Formation in the Peniny Klippen Belt. Deposits containing CORBs in the Peniny Klippen Belt are intensively deformed, in some places they are transformed into thin shale rocks or friction mud and are part of the tectonic mélange, while in the Marmarosh Klippen Zone they lie monoclinally and are weakly deformed. In the Outer Carpathians, CORBs are represented by: Turonian-Paleocene variegated shales and marls of the Holyatyn Beds (Subsilesian Nappe); Turonian-Coniacian red-colored and variegated shales belonging to the lower member of the Yalovets Formation (Dukla, Chornohora, Svydovets, and Krasnoshora nappes); and pack of Turonian variegated marls included in the Sukhiv Formation (Burkut nappe). CORBs represented by red-brown interlayers, occur both in the uppermust Albian-lower Cenomanian (Eiffellithus turriseiffeli Zone) of the Sukhiv Formation, and in the Santonian upper member of the Yalovets Formation. CORBs in the Outer Carpathians are deformed to a greater or lesser extent, plastic marls of the Sukhiv Formation are especially strongly deformed, which makes it much more difficult to establish their stratigraphic sequence. The age of the deposits of the Ukrainian Carpathians, which contain CORBs, has been clarified. The studied sediments are correlated with the Geologic Time Scale (2020) on the basis of nannoplankton and planktonic foraminifera. The biozonal scale based on nannoplankton of A.M. Romaniv is compared in the range BC27/UC0 (upper Albian - lower Cenomanian) - UC20 (upper Maastrichtian) according to the first appearance of zonal species according to the scale of J. Barnett (1998). Accordantly, the Eiffellithus turriseiffeli Zone (uppermost Albian-Lower Senomanian); Gartnerago obliquum Zone (Middle Senomanian-lowermost Turonian); Eiffellithus eximius-Marthasterites furcatus Zone (Lower Turonian-lowermost Upper Coniacian); Micula staurophora-Tetralithus obscurus-Broinsonia parca Zone (Upper Coniacian-lowermost Middle Campanian); Tetralithus aculeus Zone (Middle Campanian); Tetralithus? trifidus (Middle Campanian-lowermost Upper Campanian); Nephrolithus frequens (Upper Campanian-Upper Maastrichtian) are distinguished. The biozonal division of the Upper Cretaceous of the Carpathians according to planktonic foraminifera after N.I. Maslakova was modified and compared with the biochronozones of a typical section of the Tethys region (Coccioni, Premoli Silva, 2015). In the studied sediments, the following zones are distinguished: Thalmanninella reicheli (middle part of the Lower Cenomanian), Rotalipora cushmani (middle part of the Lower Cenomanian-Upper Cenomanian), Helvetoglobotruncana helvetica (lower part of Turonian), Dicarinella concavata (top of Turonian-lowermost Santonian), Contusotruncana fornicata (most of Santonian), Globotruncanita elevata (lower part of the Campanian), Contusotruncana morozovae (middle part of the Campanian), Globotruncanita stuarti (top of the Campanian-lower part of the Maastrichtian), Abathomphalus mayaroensis (upper part of the Maastrichtian); beds with Thalmanninella globotruncanoides (lower part of the Lower Cenomanian), assemblage with Marginotruncana schneegansi, Marginotruncana sigali, Marginotruncana renzi (upper part of Turonian). Benthic foraminifera Uvigerinammina jankoi Zone (Turonian); Spiroplectinella costata Zone (Coniacian-Lower Santonian); Caudammina gigantea Zone (Upper Santonian-Lower Campanian); Rzehakina inclusa Zone (Upper Campanian-Maastrichtian); Rzehakina fissistomata Zone (Paleocene) were identified accordantly to zonal schemes of L.D. Ponomaryova and B. Olszewska. The lower boundary of the CORBs in the Ukrainian Carpathians is correlated with the Senomanian-Turonian boundary on the basis of appearance of planktonic foraminifers of Helvetoglobotruncana helvetica Zone and benthic foraminifers of Uvigerinammina jankoi Zone in the base of both Puchov Formation (Pieniny Klippen Belt) and Holyatun Beds (Subsilesian Nappe), as well as in the lowermost part of the Yalovets Formation (Dukla, Chornohora, Svydovets and Krasnoshora nappes). [ABSTRACT FROM AUTHOR]

The taxonomic typification of dinocyst assemblages was carried out on the basis of a qualitative and quantitative assessment of their generic composition for the Northern Hemisphere in the Cenomanian–Turonian time to identify correlation taxa. Three types of dinocyst assemblages were identified in the Cenomanian. Cenomanian dinocyst assemblages are poorly differentiated; a large number of cosmopolitan genera were identified, which is in good agreement with paleobotanical data indicating a very warm, humid climate. Three types of dinocyst assemblages were established for the Turonian. The number of cosmopolitan dinocyst genera decreases and species endemism sharply increases in some Turonian basins. The differentiation of assemblages increases and their correlation potential decreases. However, the identified common genera and species of dinocysts in different types of assemblages provide the possibility of interregional correlation of Upper Cretaceous deposits at the stage, substage, and, at some sections, even more detailed levels in different climatic zones. [ABSTRACT FROM AUTHOR]

In the Lower Campanian, Pachydiscus (Pachydiscus) launayi (De Grossouvre) was found for the first time above a soap (bentonite) clay layer, which has been described well in the literature, in an abandoned quarry on the outskirts of Kudrino village in Southwestern Crimea. This finding expands our understanding of the distribution of this species and precises the biostratigraphic position of the soap clay layer. [ABSTRACT FROM AUTHOR]

Planktonic foraminifers are abundant in the Upper Cretaceous deposits of the Mountainous Crimea, and their marker species are of great importance for biostratigraphy and correlation. Globotruncanita stuarti (De Lapparent, 1918) and Pseudotextularia elegans (Rzehak, 1891) are used as index species for local and regional biostratigraphic scales, and species of the genus Rugoglobigerina Brönnimann, 1952 are used as index species for beds with fauna. The biostratigraphically important species from five sections of the Mountainous Crimea, including Pseudotextularia elegans (Rzehak, 1891), Rugoglobigerina rugosa (Plummer, 1927), R. hexacamerata Brönnimann, 1952, R. milamensis Smith and Pessagno, 1973, R. macrocephala Brönnimann, 1952, and Globotruncanita stuarti (De Lapparent, 1918), are described systematically. [ABSTRACT FROM AUTHOR]

The Cretaceous Farrokhi Formation is located in theKhur area of central Iran and yielded a reasonablywell-preserved rich planktonic foraminiferal assemblage. This formation consists of 154mof fossiliferous marl and limestone. The lower and upper bounding surfaces of the Farrokhi Formation are unconformable with the underlying Haftoman Formation and the overlying Chupanan Formation. In this research, 46 planktonic foraminiferal species belonging to 19 genera were identified and resulted in recognition of the following three biozones (from base to top); the Globotruncana aegyptiaca Interval Zone (IZ), the Gansserina gansseri IZ, and the Contusotruncana contusa IZ. This biozonal framework places deposition of the Farrokhi Formation during the late Campanian to early Maastrichtian. Biostratigraphic comparison between the samples for this research and data from three other studied sections within the Farrokhi Formation indicates that the basal and upper boundaries of the formation are time-transgressive and migrate chronologically from north to southeast. Since the first occurrences of Pseudoguembelina palpebra and Rugoglobigerina pennyi mark the latest Campanian worldwide, we approximate the Campanian/Maastrichtian boundary based on the FOs of Trinitella scotti and Rugoglobigerina hexacamerata, and identify the basal Maastrichtian by the last occurrence of Laeviella bollii. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Forty-six species of radiolarians recovered from the Upper Cretaceous Smoking Hills and Mason River formations in the Northwest Territories represent the first assemblage of this age from mainland Arctic Canada. Four interval zones and two subzones, calibrated to radiometric ages, are proposed based on the lowest and highest occurrence of index radiolarian species. These are 1) the Santonian/early Campanian Kuppelella aff. cayeuxi Zone, 2) the middle Campanian Diacanthocapsa aff. rotunda Zone (subdivided into the Kreuzstella vierkantiga and Lithostrobus borealis subzones), 3) the late Campanian Canadasphaera inuita Zone, and 4) the early Maastrichtian Stichomitra cf. communis-Xitus sp. B Zone. Integration of these radiolarian biozones with previously reported diatom, silicoflagellate, palynological and foraminiferal biozones and new radiometric ages indicate a middle Coniacian-middle Campanian age for the Smoking Hills Formation and a middle Campanian-late Maastrichtian (probably Paleocene) age for the Mason River Formation. The radiolarian assemblages reported here resemble those of the North Slope of Alaska and western Siberia, allowing for biostratigraphic correlations within the Arctic Realm. • Highly diverse Cretaceous radiolarian assemblage recovered from the Canadian Arctic. • Four radiolarian biozones identified, spanning Santonian to lower Maastrichtian. • Age refined using correlation with siliceous microfossils and radiometric dating. • Potential for an Upper Cretaceous radiolarian biozonation in the Arctic Realm. [ABSTRACT FROM AUTHOR]

The vertical ranges of inocerams, belemnites, ammonites, echinoids, sponges, and brachiopods from lithologically monotonous carbonate rocks have been studied in the Kommunar section. The results obtained in the study of macrofaunistic assemblages confirm and complement the benthic foraminifera research data of distinguished units of the middle–upper Turonian, Coniacian, lower and upper Santonian, and lower Campanian basal horizon. The stratigraphically full upper Coniacian–lower Santonian interval in the Kommunar section has been identified in the Volga region for the first time. The defined macro- and microfaunistic biostratigraphic units have been correlated and discussed. The Boreal–Tethyan magnetochronological correlation of the Santonian–Campanian makes it possible to conclude that the Santonian lower boundary in different regions differs by about a million years, which is comparable to the duration of the Santonian. [ABSTRACT FROM AUTHOR]

Bakhtiariella, a new genus of Larger Benthic Foraminifera is described from the upper Maastrichtian Tarbur Formation of Iran. The new taxon is characterised by a trochospirally coiled initial test part with angular chamber margins, later uncoiling and becoming rectilinear and presenting a coarse subepidermal network of horizontal and vertical partitions. Appearing as an extension of the subepidermal alveolar layer (exoskeleton), the pseudotriangular-shaped main partitions extend inwards and stretch downwards to the chamber floor where their arrangement is related to the inner margin of the central area with irregularly distributed pore-like foramina. Together with Persiacyclammina, which also displays such peculiar 'subepidermal septula', Bakhtiariella is included into the new family Bakhtiarellidae, and further compared with the Jurassic–Lower Cretaceous Hauraniidae. The new family gives further evidence for the diversification and pronounced endemism (Arabian Plate) of Larger Benthic Foraminifera within the final phase of the so-called Upper Cretaceous Global Community Maturation Cycle. This leads to the conclusion that both Persiacyclammina and Bakhtiariella can be considered 'Key Mesozoic Benthic Foraminifera of the Middle East'. [ABSTRACT FROM AUTHOR]

The study area is located in Tang-e Bagh at Kuh-e Genu, approximately 69 km, northern Persian Gulf. The age relationships of Sarvak, Gurpi, and Pabdeh formations were unclear in the study area because of the low-resolution biostratigraphy. Therefore, 152 samples were collected. All samples contain well-preserved foraminifers that permit clarification of the age of these formations. Nine benthic species (5 genera) and sixty-eight planktonic foraminiferal species (29 genera) were identified that were arranged eleven biozones with high resolution of biostratigraphy. Biozone I corresponds to the total range of Orbitolina qatarica in the Mauddud Member of Sarvak Formation, suggesting the Cenomanian (middle Cenomanian) age. The biozone II is characterized by the total range of Dicarinella asymetrica in the basal part of Gurpi Formation, indicating the Santonian age. Therefore, there is a hiatus between the Sarvak and Gurpi formations that includes part of the Mauddud Member, the whole Ahmadi Member, and the Ilam Formation. This hiatus encompasses the late Cenomanian to Coniacian that is marked by a few meters of Fe-stained deposits in the Kuh-e Genu; the interval range zones III to VII as well as Abathomphalus mayaroensis zone VIII (TRZ) are present within the rest of Gurpi Formation and suggests the Campanian to Maastrichtian. The biozones IX-XI are present within the Pabdeh Formation that corresponds to a Not Zone and two interval range zones (P1b, P1c-P2), suggesting Danian. Based on microfacies, texture, and paleontological analysis, a deep-water environment suggests for Gurpi and Pabdeh formations and shallow marine conditions for Sarvak Formation. [ABSTRACT FROM AUTHOR]

The results of microfaunistic (benthic foraminifers) and magnetostratigraphic (paleomagnetic and petromagnetic) studies obtained in the lower part of the Upper Cretaceous deposits of the Kommunar section are presented. On the basis of the study of benthic foraminifers, the section consists of middle and upper Turonian, Coniacian, lower and upper Santonian, and basal horizon of the lower Campanian. In addition, all Coniacian zones and subzones of the East European Platform have been established. These data confirm the importance of the Kommunar section as a stratotype of the Volsk Formation (Coniacian of the Middle and Lower Volga region). In the Kommunar section, the Turonian and Coniacian are characterized by a normal polarity, and the Santonian and lower Campanian are characterized by a reversed polarity. [ABSTRACT FROM AUTHOR]

The Upper Cretaceous Sudr Formation at Wadi El Dakhl, West Gulf of Suez (Northeast Egypt) has been described to analyze the facies and their cycles in conjunction with the influence of sea level and tectonics. The Sudr Formation (~ 130 m thick) is composed mainly of chalk and chalky limestone, with intercalations of argillaceous limestone and marl. It could be divided into two members; the Markha of the early–middle Campanian age and Abu Zenima of the late Campanian–Maastrichtian age. Biostratigraphically, nine planktonic foraminiferal zones have been recorded which encompass the studied section. Petrographic studies of the Sudr Formation led to identify five facies types; four carbonate facies and one marl facies. These facies have been deposited in the environmental conditions of an inner, middle, outer shelf, and open marine basinal setting. Two types of cyclicity have been identified: shallowing-upward and deepening-upward cycles which indicate a change in oscillation in the relative sea level. The comparison of the studied sea-level curve with the global curves of Haq et al. (Science 365:1156–1167, 1987) and Haq (Glob Planet Change 113:44–58, 2014) refer to general correspondence between them in addition to the clear effect of the tectonic events that influenced the obtained sea-level curve of the present study. Three pronounced tectonic events that impacted the deposition of the studied Sudr Formation were recorded. These tectonics were operated during the late Santonian, middle Campanian, and late Maastrichtian time interval. These tectonics are most probably related to the collision of African/Arabian and Eurasia Plates. [ABSTRACT FROM AUTHOR]

New complex data have been obtained for two sections of the Santonian–Campanian boundary of Southwestern Crimea. Article 1 presents detailed geological descriptions of sections, lithological, mineralogical, and paleoichnological materials, and the results of determining macro- (crinoids, ammonoids, belemnites) and micropaleontological (dinocysts, nannoplankton, benthic and planktonic foraminifers) remains. On the basis of the results of research, sea level fluctuations, variations in the activity of allogenic input (including pyroclastic material), and other features of sedimentation have been reconstructed. All macro- and micropaleontological data confirm the late Santonian–early Campanian age of the rocks; for each of the micropaleontological groups, biostratigraphic units have been established and a detailed division of the sections has been carried out. [ABSTRACT FROM AUTHOR]

Over the past two decades, sequence stratigraphy has proven to be a valuable tool in addressing challenges arising from the inconsistent application of lithostratigraphic nomenclature across diverse geological provinces. It has been particularly successful in achieving regional correlations within the Cretaceous deposits of the Arabian Plate. The key sequence stratigraphic surface in the currently adopted standard sequence stratigraphic scheme is the K150 SB, marking the transition from a passive to an active margin along the eastern edge of the Arabian plate. Despite its importance, the chronostratigraphic age of this surface is poorly constrained. In the Zagros FTB, the uppermost part of the Sarvak Formation, just below the K150 SB, was recently assigned to the upper part of middle Turonian to upper Turonian, based on the presence of Reticulinella ? kaeveri. Our research reveals that the range of R. ? kaeveri extends above the K150 SB as this species is also present in the Laffan and base of Ilam formations. The Last Occurrence of this taxon provides a new chronostratigraphic marker of the upper Turonian within the Ilam Formation. This finding proves that more Turonian deposit are present in the study area than was previously recognized. We have studied the deposits enclosing the K150 SB in outcrop sections and wells along a transect from basin to platform margin to inner platform setting. Based on planktonic foraminifera and calcareous nannofossils biostratigraphy of basinal sections and sequence stratigraphic correlation to carbonate platform sections, the age of the uppermost part of the Sarvak Formation, immediately below the K150 SB, is firmly constrained within the interval lower Turonian–lower part of middle Turonian. Sequence stratigraphic correlation from basin to platform interior reveals also that the oldest deposits above the K150 SB are not younger than late Turonian. Our new data represents a significant improvement in the chronostratigraphic calibration of sequence stratigraphy in the Cretaceous of the Zagros fold-and-thrust belt. [ABSTRACT FROM AUTHOR]

Four rudist assemblages: lower Turonian, upper Turonian, upper Coniacian, and Santonian–?Campanian, are distinguished in the shallow water carbonate platform successions of the Iberian Basin, nowadays Iberian Range, a Mesozoic intra-continental basin in the western margin of the Mediterranean Tethys. Because of the depositional evolution of the Iberian Basin, the occurrence, abundance, taxonomic diversity, diagenetic processes, and shell preservation, for each assemblage, is linked, both, to the shallow character of these carbonate platform successions, and the successive high and low frequency sea level falls. Twenty identified rudist taxa are described and figured: Hippuritidae, six species of two genera; Radiolitidae, ten species of six genera, one new, Hoyosites tozoi gen. et sp. nov; Requieniidae, one genus. The knowledge of the shell characters of some taxa has been improved and the taxonomic, biostratigraphic, and palaeobiogeographic significance of most of them increased. The precise positioning of the first three rudist assemblages in high-frequency depositional stacking pattern (parasequence sets) and their correlation and calibration with ammonite biozones provide biostratigraphic datums of great importance. This fact notably improves the chronostratigraphic framework of the Cretaceous sedimentary successions of the Iberian Basin, especially towards the coastal margins, and allows the accurate quantification of the hiatuses associated with the parasequence sets boundaries, so enabling their precise hierarchization. • Seventeen rudist species (Hippuritidae and Radiolitidae) described and figured. • Intraspecific variability shown by figures of many specimens for each species. • A new upper Turoian radiolitid, Hoyosites tozoi gen. et sp. nov. • Three rudist assemblages positioned within sequence stratigraphy framework, calibrated with ammonite biozones. [ABSTRACT FROM AUTHOR]

The results of a palynological study of the Upper Cretaceous and Paleogene sediments of three boreholes drilled in the South Transurals are presented. The Upper Cretaceous Kuznetsovo, Kamyshlov, Zaikovo, Fadyushino, and Gan'kino formations are exposed by Boreholes 3, 9, and 13, which contain four spore and pollen biostratons. Five dinocyst biostratons are identified for the first time: local zone with Chatangiella spectabilis, local zone with Spinidinium sverdrupianum, local zone with Chatangiella chetiensis, local zone with Chatangiella manumii–Dinogymnium spp., and local zone with Cerodinium diebelii. The comparison of the Late Cretaceous dinocyst assemblages of the southern and northern territories of Western Siberia shows that, in spite of significant provincialism of dinoflagellates, there is a series of stratigraphic intervals in the middle–upper Turonian, lower Coniacian, lower Santonian, Campanian, and lower Maastrichtian, which have interregional correlation potential. In the Talitsa, Serov, Irbit, and Chegan formations, intervals of six zones of the Thanetian–Bartonian age of the dinocyst scale of Western Siberia are identified in Borehole 9 (Alisocysta margarita, Apectodinium hyperacanthum, Deflandrea oebisfeldensis (acme), Dracodinium simile, Rhombodinium draco, and Rh. ornatum), as well as five local zones by spores and pollen. The Kurtamysh Formation is characterized by a Rupelian spore and pollen assemblage. Significant sedimentation hiatuses in the Cretaceous–Paleogene sequence corresponding to the upper part of the Maastrichtian, the most part of the Danian and Selandian, the lowermost parts of the Ypresian, middle–upper Ypresian, Lutetian, the upper parts of Bartonian, Priabonian, and the lower parts of the Rupelian are established. [ABSTRACT FROM AUTHOR]

In this study, an Upper Cretaceous sedimentary sequence in the Anaran Anticline (located in the central Zagros) is investigated to assess planktonic foraminiferal biozonations and implications for sea level changes. The thickness of this sequence is about 215 m, characterized by shales and limestones with thin marly limestone intercalations. In total, 51 species and 22 genera of planktonic foraminifera in 12 biozones spanning the middle Campanian to late Danian ages were delineated in the studied sequence. Additionally, planktonic foraminiferal morphological models, species abundance percentages, and the planktonic/benthonic foraminiferal ratio (P/B) ratios were assessed to reconstruct changes in sea level. The statistical studies on the different genera and species and the P/B ratio from the base to the top of the sequence indicate sea level transgressions during the middle Campanian and Maastrichtian in the Contusotruncana plummerae Interval Zone, Radotruncana calcarata Total Range Zone, Globotruncanella havanensis Partial Range Zone, Globotruncana aegyptiaca Interval Zone, Contusotruncana contusa Interval Zone, and part of the Abathomphalus mayaroensis Interval Zone. Moreover, species belonging to the deep-water morphotype (G. arca, G. hilli, G. linneiana, and G. ventricosa) are mostly present. Furthermore, two intervals of this sequence are associated with falling sea levels: 1) at the Campanian/Maastrichtian boundary in the middle of the Gansserina gansseri biozone; 2) from the late Maastrichtian close to the Cretaceous/Paleogene boundary with marly lithology. [ABSTRACT FROM AUTHOR]

An upper Campanian to upper Oligocene stratigraphic succession has been examined from six deep exploration wells in the Palmyrides area of Syria. Most of the sedimentary succession contains rich and well to moderately preserved planktonic foraminiferal assemblages that enable successful age determination. The upper Campanian and Maastrichtian planktonic fauna is highly diverse with domination of warm water taxa such as Globotruncana aegyptiaca, Gansserina gansseri, Globotruncanella havanensis, Globotruncanita angulata and Pseudotextularia elegans. The most dramatic turnover occurred across the Cretaceous/Palaeocene boundary when most planktonic foraminiferal species became extinct. The oldest Palaeocene planktonic foraminiferal assemblage, rich in the number of specimens, but not very diverse, includes the following species: Eoglobigerina eobulloides, Globanomalina archeocompressa, Chiloguembelina morsei, Woodringina claytonensis and Parasubbotina pseudobulloides. The late Palaeocene is marked by origination of the morozovellids, acarininids and globanomalinids, while the early Eocene is characterized by a tropical assemblage, dominated by muricate species, and by intensive speciation of Acarinina and Subbotina in the latest part. Most of these species continue into the middle Eocene and become a significant component of the planktonic community. The middle Eocene is characterized by intensive speciation and domination of warm water genera such as Acarinina, Morozovelloides, and to a lesser degree Turborotalia, Globigerinatheka and Hantkenina. The middle/late Eocene boundary is marked by double extinction of the last muricate taxa Acarinina mcgowrani and Morozovelloides crasssatus, which indicate a variable climate, water column instability, and loss of surface habitats. In contrast, Turborotalia and Globigerinateheka become more important in the late Eocene. The Eocene/Oligocene boundary is marked by the extinction of most warm water taxa including Turborotalia cerroazulensis group, Hantkenina, Globigerinatheka and some subbotinids. The beginning of the early Oligocene is indicated by the domination of cool water taxa such as Dentoglobigerina, Globorotaloides, Tenuitella and Chiloguembelina. Speciation of the spinose surface dweller Ciperoella ciperoensis group reflects warming in the late Oligocene. The combined observations of lithology with the diversity and composition of planktonic foraminifera assemblages indicate that the Palmyrides area in Syria was a Tethyan bioprovince with a tropical to subtropical climate from the late Campanian to the end of the Eocene with deposition in deep sea environments (upper bathyal to outer shelf). In contrast, Oligocene deposits and their microfossil content suggest temperate to warm climate conditions and sedimentation in middle to inner shelf environments. [ABSTRACT FROM AUTHOR]

Planktonic foraminifera are one of the most stratigraphically important groups of organisms for the Cretaceous system. However, standard foraminiferal zonations based mostly on species from the Tethyan bioprovince are hardly applicable in temperate regions where warm-water taxa are scarce or lacking. We propose a foraminiferal zonation based on foraminiferal events recognized in the northern Foraminiferal Transitional Bioprovince, which likely has a high correlation potential at least at a regional scale. Fifteen planktonic foraminiferal zones are distinguished from the upper Albian up to the uppermost Maastrichtian strata in extra-Carpathian Poland and western Ukraine. From the bottom to the top, Thalmanninella appenninica, Th. globotruncanoides, Th. reicheli, Rotalipora cushmani, Whiteinella archaeocretacea, Helvetoglobotruncana helvetica, Marginotruncana coronata, M. sinuosa, Pseudotextularia nuttalli, Globotruncana linneiana, G. arca, Contusotruncana plummerae, Rugoglobigerina pennyi, Globotruncanella petaloidea and Guembelitria cretacea. These zones are calibrated by macrofaunal zonations.

An Upper Cretaceous deep marine unit containing planktonic foraminifera was studied based on the material recovered from a subsurface section at the northern part of the Moghan area. The unit contains a relatively diverse assemblage of planktonic foraminifera, which allowed identifying a number of three biozones spanning the late Santonian to early late Campanian. These are Dicarinella asymetrica Zone, Globotruncanita elevata Zone, and Globotruncana ventricosa Zone. Based on the stratigraphic values of the identified planktonic foraminifera, a late Santonian to middle-late Campanian age is ascribed to the examined strata. The biostratigraphic results also point to the earlier marine transgression in the northern Moghan area starting in the late Santonian. Our biostratigraphic results indicate a prominent stratigraphic hiatus at the contact of Upper Cretaceous unit with the overlying Sarmatian strata, comprising the late Campanian to middle Serravallian. [ABSTRACT FROM AUTHOR]

A new larger benthic foraminifera is described as Broeckinella hensoni from the upper Maastrichtian Tarbur Formation of SW Iran (Zagros Zone). In comparison to the type species of the genus, Broeckinella arabica Henson, which also occurs in the Tarbur Formation, the new species has distinctly larger dimensions (e.g., size and thickness of test, chamber height). The first record of a microspheric specimen of B. arabica shows previously unrecorded annular chambers in the final test stage. Therefore, the generic diagnosis is herein emended. In the Tarbur Formation, both B. hensoni n. sp. and B. arabica occur in foraminiferal-algal wackestones. However, B. arabica occurs in a wider range of microfacies, including packstones and grainstones. It is assumed that Broeckinella originated in the Upper Cretaceous with Broeckinella neumannae Gendrot. The upper Albian Broeckinella aragonensis Peybernès is herein transferred to the porcellaneous genus Peneroplis Montfort. [ABSTRACT FROM AUTHOR]

The most stratigraphically representative section of Turonian–Coniacian in the right-bank part of the Volga region is found at the Kamennyi Brod-1 section (Olkhovka district of Volgograd oblast). The subdivision of carbonate rocks into zones is based on the complexes of benthic foraminifera and other accompanying groups of invertebrates. Regressive-transgressive tendencies in the evolution of the Turonian–Coniacian basin is also reflected in the quantitative ratio between benthic and planktonic foraminifera. The earlier unknown representatives of Turonian and Coniacian marine biota are revealed: silicon sponges, crinoids, starfish, brittle stars, and brachiopods. The magnetostratigraphic (magnetopolar and petromagnetic) characteristic of the section is obtained, and the magnetic zone of anomalous polarity is revealed against the background of normal polarity (N). It is supposed that anomalous directions of magnetization represent the stabilized vector sum of oppositely directed components, one of which (corresponding to reverse polarity) is the primary one. [ABSTRACT FROM AUTHOR]

The results of palynological and micropaleontological studies of the Upper Cretaceous–Cenozoic strata penetrated by Boreholes 23 and 19 of the Aleiskaya area (Altai krai) are presented. The obtained data allowed us to substantiate the age of the deposits, make suggestions concerning their depositional environment, and to clarify the subdivision of geological section into formations. Two palynological assemblages were recognized in the Cretaceous part of the Borehole 23 section: the first one characterizes the Len'ki Formation and is dated as Cenomanian–Turonian; the second one is recognized in the Upper Sym Subformation and is dated as Maastrichtian. The Upper Cretaceous sequence is overlain by the terrestrial Ostrovnoe Formation (Paleogene). In Boreholes 19 and 23, this formation contains presumably Late Paleocene–Early Eocene and Middle Eocene spore and pollen spectra, respectively. Palynological data substantiate the Late Miocene age of sedimentary strata in the upper part of the geological section of Borehole 23 and their belonging to the Pavlodar Formation. The structure of the palynological assemblages, the specific features of the macerate, and the absence of foraminifers indicate the continental genesis of the Upper Cretaceous–Paleogene sedimentary deposits in the southern part of the Kulunda Depression in Altai krai. [ABSTRACT FROM AUTHOR]

The Rosario section in northern Coahuila, northeastern Mexico, contains a complete record of distal shelf deposits across the Turonian-Coniacian boundary. Here we describe the ammonoids, the biozonation based on these cephalopods, their taphonomy and some palaeobiogeographic relations. Gaudryceras mite , Peroniceras (P.) tridorsatum , P. (P.) dravidicum , Forresteria (F.) alluaudi , F. (F.) brancoi , F. (F.) peruana , Baculites sweetgrassensis , B. yokoyamai , Neocrioceras maximum , Schlueterella stinnesbecki , Scaphites (S.) frontierensis , S. (S.) preventricosus , S. (S.) sagensis , and S. (S.) uintensis were identified at El Rosario and a nearby complementary outcrop at Carranza. The lower Coniacian Scaphites preventricosus, F. (F.) alluaudi, P. (P.) dravidicum and Neocrioceras maximum zones are represented and provide correlation with sections of the US Western Interior and Europe. The original index for the base of the Coniacian, F. (F.) peruana is also present, although few data exist below the Turonian-Coniacian boundary level. The ammonoids were not transported far before deposition, indicated by their preservation and size distribution. A moderate diversification in open-coiled diplomoceratids seemed to have started in the early Coniacian in this region. The El Rosario section provides a detailed ammonoid record and biozonation, and it is one of very few sections in the world where it can be correlated with the standard inoceramid biozonation. [ABSTRACT FROM AUTHOR]

A new microgranular-imperforate foraminifera, attributed to the family Pfenderinidae, is described as Pseudochablaisia subglobosa gen. et sp. nov. from the upper Maastrichtian Tarbur Formation (Zagros Zone, SW Iran). It occurs in inner platform wackestones/packstones associated with other larger benthic foraminifera (e.g., Loftusia , Omphalocyclus , Gyroconulina) and dasycladacean green algae (e.g., Cymopolia , Dissocladella , Thyrsoporella). Pseudochablaisia gen. nov. is compared with possible ancestral morphotypes, the Middle Jurassic to Oxfordian homeomorph Chablaisia Septfontaine, 1978 and sections of a taxon classically assigned to the middle-Late Cretaceous " Nezzazatinella " Darmoian (1976) which type-material is incompletely known from loose isolated specimens. These two homeomorphic taxa and the new genus Pseudochablaisia possess a trochospirally coiled test, with a pseudokeriothecal wall texture (sometimes hardly visible). The central structure of the test comprises an umbilical ("siphonal") hollow columella in early stages continuing in a deep umbilical cavity in later stages. The chamber interior is occupied by a zone of coalescence of the septa and a septal button, lacking in sections of " Nezzazatinella ". [ABSTRACT FROM AUTHOR]

This study describes and interprets Upper Cretaceous volcaniclastics interbedded with hemipelagic to pelagic limestones, marls, and turbidites from the Western Pontides, northwestern Turkey. The Dereköy Formation, the Unaz Formation (red pelagic limestone unit), and the Cambu Formation can be distinguished, overlain by the turbiditic Akveren Formation. Biostratigraphic ages from the predominantly volcaniclastic Dereköy Formation indicate Turonian (Dicarinella concavata planktonic foraminifera zone, CC13/UC8-9 nannofossil zones) to middle/late Santonian ages up to CC17/UC13. The Unaz Formation, deposited during the late Santonian (UC13, Dicarinella asymetrica Zone), is overlain by the volcaniclastic Cambu Formation of latest Santonian (CC17b/UC13) to early/middle Campanian (CC20/UC15a) age. However, turbidite intercalations are already present diachronously from CC19/UC14d onwards, and the turbiditic Akveren Formation ranges up into the late Maastrichtian (Abathomphalus mayaroensis Zone). Geochemistry of the volcaniclastic units reveals information about the volcanic series and tectonic setting, although element mobility has to be considered. An overall trend of calc-alkaline to high-K calc-alkaline series and basaltic to basalt-andesitic rock types was identified. A negative Nb anomaly with respect to Th and Ce in all samples confirms the existence of a volcanic arc, also indicated by a negative Ti anomaly. Biostratigraphic age constraints give evidence for volcanic arc activity mainly between Turonian and early Campanian, ca. 91 - 79 Ma. Various geochemical data, especially element variations normalized to N-MORB, show two types of volcanic arc basalts (VAB): (1) Calc-alkaline to high-K calc-alkaline VAB have increased Nb and Zr values, (2) more tholeiitic VABs are depleted in Nb, Zr, Ti, V. The volcaniclastics successions were deposited in an arc setting triggered by different stages of subduction of the Neotethys Ocean to the south and contemporaneous spreading in the Western Black Sea Basin to the north. An extensional regime caused formation of small but deeper-water sedimentary basins along the southern shore of the Black Sea where volcaniclastic complexes interfingered within short lateral distances with pelagic and mass-flow deposits. [ABSTRACT FROM AUTHOR]

Anew pfenderinid taxon is described as Pachycolumella nov. gen. with the two species P. elongata n. sp. (type-species), and P. acuta n. sp. The type material comes from the upperMaastrichtian Tarbur Formation of the Zagros Zone, SWIran. Areconstruction of Pachycolumella nov. gen is presented including allmorpho-structural elements such as a conspicuous central columella. The wall of the elongate and triserially coiled test is microgranular-agglutinated displaying a pseudokeriothecal texture. Pachycolumella species are also reported from the Paleocene (Danian-early Thanetian) of Turkey,Oman, Iran (this paper), India, and Pakistan, thus representing aK-Pg survivor taxon. In Iran Pachycolumella is reported from various localities belonging to both the former northern and the southern Neo-Tethyan margin. In the western Neo-Tethyan realm (e.g., Adriatic Carbonate Platform), Pachycolumella seems to be absent. [ABSTRACT FROM AUTHOR]

Abstract Biostratigraphy of Santonian-Danian calcareous nannofossils and planktonic foraminifera was studied in Göynük village and close surroundings located in northwest Turkey. Calcareous nannofossil and planktonic foraminifera assemblages from this time interval were investigated in detail in seven stratigraphic sections measured in the Değirmenözü Member, Yenipazar Formation and Seben Formation. The UC12 zone in the Santonian, UC13 zone, UC14a-bTP and UC15a-b-c-dTP subzones in the Campanian and UC20a-b-c-dTP subzones in the Maastrichtian were defined with nannofossil species assemblages. Planktonic foraminifera assemblages determined included Dicarinella asymetrica Total Range Zone (TRZ) from the Santonian, Globotruncanita elevata Partial-range Zone and Globotruncana ventricosa Partial-range Zone from the Campanian and Racemiguembelina fructicosa Partial-range Zone and Pseudoguembelina hariaensis Partial-range Zone from the Maastrichtian. There was a significant reduction in nannofossil species at the Cretaceous-Paleogene (K-Pg) boundary with dominance of Braarudosphaera bigelowii, Thoracosphaera sp. and Markalius inversus species and increased abundance of biserial planktonic foraminifera species. Just above this boundary in the Danian NP1 and NP2 nannofossil zones and Parvularugoglobigerina eugubina Taxon-range Zone, Parasubbotina pseudobulloides Partial-range Subzone (P1a) , S. triloculinoides Lowest Occurrence Subzone (P1b), and G. compressa/Praemurica uncinata Lowest Occurrence Subzone (P1c) were identified from planktonic foraminifera. Highlights • Detailed nannofossil and planktonic foraminifera biostratigraphy was studied for the Değirmenözü Member, Yenipazar Formation and Seben Formation. • Seven nannofossil zones and nine planktonic foraminifera zones from the Santonian to the Danian. At the K-Pg boundary, Braarudosphaera bigelowii, Thoracosphaera sp. and Markalius inversus nannofossils are dominantly observed with biserial and smalldimension planktonic foraminifera species common. [ABSTRACT FROM AUTHOR]

Four new species of larger benthic foraminifera are described from lower–middle Campanian inner-platform carbonates of the island of Brač, Croatia: Bakhtiarella minima sp. nov. (family Bakhtiarellidae), Biconcava brattiana sp. nov. (family Mayncinidae), Paravanneauina campaniana gen. et sp. nov. and Calveziconus pygmaeus sp. nov. (family Orbitolinidae). The latter two taxa are also reported from time-equivalent strata of the Gavrovo–Tripolitza Platform, southwestern Greece. The new taxa provide further evidence for the pronounced Campanian diversification within the Late Cretaceous Global Maturation Cycle of larger benthic foraminifera in the inner platform facies of the Mediterranean Adriatic Carbonate Platform. [ABSTRACT FROM AUTHOR]

Recognizing the ranking optime sequence of fossil dinoflagellate cysts can be a challenge for qualitative biostratigraphy. For this reason, we present the result of a quantitative stratigraphic study through probabilistic analysis of six wells from Baja California (Mexico) and six from the Gulf of Suez and the Mediterranean Sea (Egypt), which allows us to recognize 22 species of dinoflagellate cysts in an optimal sequence with 95% probability for the Upper Cretaceous in subtropical areas of the Northern Hemisphere. Photoautotrophic species represent the largest number in the database (159 species), indicating that they are the main producers, while heterotrophic species are in the minority (74 species). Spiniferites and Florentinia are the most abundant and diverse taxa, which, together with the absence of the genus Impagidinium , indicates a shallow marine depositional environment. The quantitative analysis estimates an optimal classified succession that allows the Upper Cretaceous to be divided into five groups (G1 to G5) of species communities with similar ages. The greatest species diversity is found in group G4, associated with the Maastrichtian, and the least in group G1, associated with the early Cenomanian to early Turonian. These results and comparison with previous studies using the same method of quantitative biostratigraphy suggest a similarity of paleoenvironmental conditions in subtropical regions of the Northern Hemisphere and tropical regions during the Upper Cretaceous. • Statistically valid sequence of dinoflagellate events in Upper Cretaceous, in subtropical regions of the northern hemisphere. • Sequence effective in the Gulf of California and the Gulf of Suez. • Upper Cretaceous subtropical of the northern hemisphere dinoflagellate assemblages led by gonyaulacoid shallow water taxa. [ABSTRACT FROM AUTHOR]

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) theobaldianum (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. [ABSTRACT FROM AUTHOR]

Anew larger benthic foraminifera is here described as Neodubrovnikella maastrichtiana n. gen., n. sp. from thin-sections of the upperMaastrichtian Tarbur Formation of southwestern Iran (Zagros Zone). This Maastrichtian genus is homeomorphic to the Middle Jurassic Dubrovnikella Schlagintweit and Velié. Differences are due to the type of foramina and the coarseness/fineness of the pores in the wall. Neodubrovnikella n. gen. represents the second taxon ascribed to the Biokovinidae besides Zagrosella Schlagintweit and Rashidi due to the presence of a pseudokeriothecal wall texture. Representatives of this family exhibited a latest Cretaceous "revival" before finally becoming extinct at the K/Pg boundary. In agglutinating conical forms however the pseudokeriotheca may be still present in the Early Paleogene. [ABSTRACT FROM AUTHOR]

The distribution and stratigraphic potential of the family Prunobrachidae Pessagno are studied. The recent discovery of new locations of the Prunobrachidae representatives in the Northeast of Russia increases the correlation potential of this family. In the Pacific Province in the Northern Hemisphere, the northernmost location of the prunoid radiolarians, is in the Chaun Bay region at 69° N (in modern coordinates) and the southernmost location is the Shikotan Island (Lesser Kuril Ridge) at 43° N. The biostratigraphic subdivision as the layer with Prunobrachium articulatum was first traced in the sections of the Koryak Highlands, Kamchatka Peninsula, and Shikotan Island. The level with Prunobrachium articulatum can be traced from the Russian Platform through the Urals and Western Siberia to the Pacific Margin. [ABSTRACT FROM AUTHOR]

Well-preserved Late Cretaceous (Coniacian–Early Maastrichtian) radiolarians from the Perapedhi, Moni and Kannaviou formations (Cyprus) were investigated. Abundant and diverse members of the family Pseudoaulophacidae are recognized and studied. The description of the species Pseudoaulophacus lenticulatus and Pseudoaulophacus pargueraensis are emended. A new radiolarian genus Pseudoalievium with two new species ( P. parekklisiense and P. inflatum ), one new species of the genus Alievium ( A. mangaleniense ) and one new species of the genus Pseudoaulophacus ( P. decoratus ) are described. Geographical and stratigraphical ranges of the studied taxa of the family Pseudoaulophacidae are more exactly defined. Several rare species of this family are traced in the Tethyan Realm. [ABSTRACT FROM AUTHOR]

The planktic foraminifera from two sedimentary sequences of the Upper Cretaceous recovered by the Deep Sea Drilling Project (DSDP) Leg 80, Site 549 and Site 550 (Hole 550B) in the Goban Spur region were analysed in order to refine and integrate the zonal schemes for this area of the North Atlantic Ocean. In the studied intervals, 75 samples were analysed, and 88 species of planktic foraminifera were recognized, enabling the identification of the following biostratigraphic zones: Rotalipora cushmani (upper Cenomanian); Helvetoglobotruncana helvetica (lower Turonian); Dicarinella concavata (upper Turonian–Coniacian); Dicarinella asymetrica (upper Coniacian–Santonian); Racemiguembelina fructicosa and Abathomphalus mayaroensis (upper Maastrichtian). Two intervals in Hole 550B are likely correlative to composite biozones Pseudoguembelina palpebra/Gansserina gansseri (Campanian–Maastrichtian) and Racemiguembelina fructicosa/Abathomphalus mayaroensis (upper Maastrichtian). These zones indicate that the studied intervals were deposited from the late Cenomanian to the late Maastrichtian. The presence of high values (>6.6%) of Total Organic Carbon (TOC) in section 549-27-1 might be related to the Oceanic Anoxic Event 2 (OAE 2), globally recorded across the Cenomanian–Turonian boundary transition. The extinction of the Rotaliporidae family was observed in both sections and was associated with the onset of OAE2 in Site 549. [ABSTRACT FROM AUTHOR]

This article proposes a biostratigraphic scheme for the Upper Cretaceous of the East European Platform on the basis of the distribution in the sections of three groups of microfossils: foraminifera (both planktonic and benthic), radiolarians, and nannoplankton. Most of the stage and substage boundaries are confirmed by macropaleontological data. The most divided units are those distinguished based on benthic foraminifers and nannoplankton. The diversity of these microfossils and their constant presence allowed us to identify zones and subzones, while it is possible to subdivide only the beds by planktonic foraminifers and radiolarians. The most favorable stages in the development of plankton biota can be considered the Turonian-Coniacian interval when the basins of the East European Platform experienced an intensive influence from warm waters of the Tethys Ocean. The global Campanian cooling is clearly recorded, which affected the taxonomic diversity of all microfossil groups. [ABSTRACT FROM AUTHOR]

The detailed study of Boreholes 8, 10, and 2 in the Russkaya Polyana district (Omsk Trough) made it possible to reveal the complex structure of the Upper Cretaceous sediments formed in unstable conditions of the marginal part of the Western Siberian basin. The Pokur, Kuznetsovo, Ipatovo, Slavgorod, and Gan'kino formations were subjected to palynological analysis and substantiation of their Late Cretaceous age. Eight biostratigraphic units with dinocysts and five units with spores and pollen from the Albian to the Maastrichtian were identified. The joint application of biostratigraphic and magnetostratigraphic methods made it possible to reveal the stratigraphic breaks in the studied sedimentary stratum and to estimate their scope. The age of the Lower Lyulinvor Subformation was specified in the marginal part of the Omsk Trough. The ingression traces of the Western Siberian basin in the Albian were found for the first time in the considered region. [ABSTRACT FROM AUTHOR]