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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]

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]

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]

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]

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 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]

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]

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]

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]

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]

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]

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]

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]

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. [ABSTRACT FROM AUTHOR]

Hydrocarbon exploration involving the Urucutuca Formation is taking place in several basins located mainly in the central segment of the eastern Brazilian margin, including the Almada Basin. Relatively rich accumulations of organic material and promising prospects, especially for gas, have been discovered. The Brazilian National Petroleum Agency (ANP) considers the Urucutuca Formation as a speculative play exploratory (Urucutuca-Urucutuca) in deep and ultra-deep areas of the Almada Basin, including others. The focus was on improving the understanding of the sediments of the Urucutuca Formation and establishing a palynostratigraphic outline for the upper cretaceous strata, which still need to be updated. Therefore, integrated palynological, palynofaciological, and organic-geochemical (total organic carbon -TOC) investigation methods were carried out. For this purpose, 250 m of well 1-SST-01, drilled in the onshore part of the Almada Basin in Bahia State, were analyzed using 26 core samples along the Urucutuca Formation. By typifying palynofaciological variations based on organic matter content in conjunction with palynological and geochemical data, it was possible to distinguish three palynofacies with different characteristics of the marine influence environment. Palynofacies 1, the amorphous organic matter (AOM) group, predominates with proportions up to 54.1 and a TOC of 0.75%. The high phytoclasts percentage (70%) and a TOC content of 1% characterize the Palynofacies 2. Palynofacies 3, on the other hand, has the highest content of marine palynomorphs (40%). The analysis of total organic carbon yielded values ranging from 0.04% to 1.85%, which were heterogeneously distributed throughout the borehole. The palynological succession showed a dominance of representatives of continental origin. However, marine elements (dinoflagellates and microforaminiferal inner tests) are present throughout the section. Two expressive occurrences of dinoflagellate cysts are evident throughout the section. In the basal and middle portions, quantity and diversity suggest transgressive events or at least sea-level fluctuations. Biostratigraphically, the unit could be placed in the Tricornites elongatus (P-470) Biozone of the Crassitricolporites brasiliensis (P-450) Superzone and assigned to the Eomaastrichtian. These biostratigraphic units are consistent with the proposed zonation for other basins of the Brazilian Atlantic margin. Palynofacies and palynological data allowed the observation of variations in a predominantly platform paleoenvironment, sometimes distal and sometimes more proximal, with possible transgressions. • Palynological analysis revealed assemblages consisting of sporomorphs and dinocysts. • The Biozone Tricornites elongatus has been identified. • The amount of opaque phytoclasts increases in areas more distal to the coastline. • The range is predominantly composed of peridinoids indicating marginal marine area. • The Tricornites elongatus Zone was positioned in the EoMaastrichtian. [ABSTRACT FROM AUTHOR]

Two new genera, comprising three new species, of marine algal cysts are described here. The extinction horizons of all three occur with a high degree of consistency in many petroleum wells in the Alaska North Slope region. These horizons provide useful correlation events within the overall progradational sediments which filled a large and complex depositional basin during Cenomanian–Turonian time. The newly described taxa areParanelsoniella woodiigen. et sp. nov.,P. minutagen. et sp. nov. andXanthocysta ovatagen. et sp. nov. [ABSTRACT FROM PUBLISHER]

A sequence biostratigraphic analysis has been done for the Upper Cretaceous-Lower Paleogene sedimentary outcrops at Wadi Raha, Sudr El-Hetan and Wadi El-Giddi areas in west-central Sinai. The sequences are subdivided into four carbonate rock units; from base to top: the Wata, Themed, Sudr and Waseiyit formations. The biostratigraphic analysis of the studied samples led to the identification of two main planktonic foraminiferal zones, three benthic foraminiferal zones with the ammonite zone. Eleven microfacies associations are recorded in the rock units. Nine constitutes a limestone facies with one constitutes a dolostone facies and one a claystone facies. The stratigraphic data, and the facies study support the identification of three major breaks (sequence boundaries) and four depositional sequences. The depositional sequences are subdivided into four supercycles and seven cycles of 3rd order. The oldest break (∼90-88.5Ma.) exists at the top of the Wata Formation coincides with the intra Turonian drop in the global sea level with the initiation of the Syrian Arc inversion phase. The second major break (85 - ∼75Ma.) coincides with the major inversion phase and the evolution of the doubly plunging anticlines. The third major break (∼68 through ∼53Ma.) represents the last phase of the Syrian Arc inversion and complete the missing of Paleocene sequences. [ABSTRACT FROM AUTHOR]

The Upper Cretaceous of the Elbe Valley in Saxony and the erosion outliers west of it mark an Upper Cretaceous NW--SE-running strait between the Westsudetic Island in the NE and the Mid-European Island to the west. This street connected the NW-German-Polish Basin in the north and the Bohemian Cretaceous Basin (and adjacent regions of the Tethys) in the south. However, post-Cretaceous erosion north of Meißen removed any Upper Cretaceous deposits but erosion outliers at Siebenlehn and especially north of the Forest of Tharandt proof the presence of a marly through silty belt in this area. Three transgressions (base of uppermost Lower to Middle Cenomanian, base of Upper Cenomanian and base of the geslinianum Zone in the mid-Upper Cenomanian) have taken place. The sedimentation was infuenced by the topography of the mentioned islands and by movements at structural lines in the Proterozoic and Palaeozoic basement. During the early Late Cenomanian, a marly-silty sedimentation (Mobschatz Formation) in the north existed besides sandy sedimentation in the south (Oberhäslich Formation). The transgression at the base of the geslinianum Zone caused the fnal submergence of island chains between Meißen, Dresden and Pirna, and a litho- and biofacies bound to cliffs and submarine swells formed. A silty--marly lithofacies, a mixed sandy--silty lithofacies (Dölzschen Formation) and a sandy lithofacies in the south (Sächsisches Elbsandsteingebirge) co-existed during the latest Cenomanian. The frst mentioned biofacies yields a rich fauna mainly consisting of oysters, pectinids, rudists, and near-shore gastropods accompanied by echinids and, in some cliffs, teeth of sharks. The Pennrich fauna (Häntzschel 1933; Uhlig 1941) especially consists of the very common serpulids Pyrgopolon (P.) septemsulcata and Glomerula lombricus (formerly Hepteris septemsulcata and G. gordialis). [ABSTRACT FROM AUTHOR]

The results of complex palynological and microfaunistic studies of Upper Cretaceous and Cenozoic deposits of the Bakchar iron ore deposit are presented. Geochronologically, the age of the deposits varies from Campanian to Quaternary. It was established that the Slavgorod, Gan'kino, and Jurki (?) formations contain four biostratons in the rank of beds with dinocysts and three biostratons in the rank of beds with spores and pollen. The Cenozoic continental deposits contain four biostratons in the rank of beds, containing spores and pollen. As a result of the study, a large stratigraphic gap in the Cretaceous-Paleogene boundary deposits, covering a significant part of the Maastrichtian, Paleocene, Ypresian, and Lutetian stages of the Eocene, was established. The remnants of a new morphotype of heteromorphic ammonites of genus Baculites were first described in deposits of the Slavgorod Formation (preliminarily, upper Campanian). The distribution features of the different palynomorph groups in the Upper Cretaceous-Cenozoic deposits in the area of study due to transgressive-regressive cycles and climate fluctuations were revealed. [ABSTRACT FROM AUTHOR]

The Kocaeli Peninsula (NW Turkey) provides one of the best exposed deep marine Upper Cretaceous-Palaeocene sections in north-western Anatolia. The biostratigraphic framework from three sections, namely Belen, Bulduk, and Toylar, in the southern part of the Kocaeli Peninsula is established by means of planktonic foraminifera. A very rich planktonic foraminiferal assemblage analysed both in thin sections and washed residues records a biozonation ranging from the Contusotruncana contusa (CF6) Zone (Maastrichtian) to the Globanomalina pseudomenardii (P4) Zone (Thanetian). Although a major part of the biozones in the studied interval is clearly defined, the upper three zones (CF1-3) of the latest Maastrichtian and the P0 and P1a zones of the earliest Palaeocene cannot be recognised. These unrecorded biozones are either completely missing or occurred within a very condensed interval in the studied sections. A hardground layer characterised by oxidation and extensive bioturbation might indicate a possible biostratigraphic gap spanning the CF1-3 zones of the uppermost Maastrichtian in the Belen and Bulduk sections. In the Toylar section, on the other hand, the CF1-3 zones still cannot be detected although a hardground layer is not observed. The biostratigraphic resolution across the Cretaceous-Palaeogene (K-Pg) boundary in the studied sections cannot be improved due to the condensed and well-cemented pelagic carbonates of the boundary interval. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In this study, two stratigraphic sections of the Tarbur Formation named Kuh-e Gadvan and Kuh-e Tir were selected. The thicknesses of the whole sediments of the sections studied are about 1100 m of which 400 thin sections were studied. Two biozones are determined in Kuh-e Gadvan and three biozones are described in Kuh-e Tir section. According to established biozones, the age of Tarbur Formation of Kuh-e Gadvan section is assigned to Campanian-Maastrichtian and Tarbur Formation age determination shows relation to Maastrichtian-Lower Paleocene in Kuh-e Tir section. Seven major lithofacies are distinguished along two studied stratigraphic columns which are foraminifer-bioclast wackestone, algal-foraminifer- intraclast wackestone, rudist biclast wackestone, bioclast packstone, bioclast-intraclast grainstone, coral and rudist boundstone. According to the recognized lithofacies, paleoenvironment of the Tarbur formation consists of lagoon, open margin of the reef landward, margin of the reef, flat reef, and seaward margin of the reef. Comparison of studied sections allows that geologic setting had been controlled biostratigraphy and facies change. [ABSTRACT FROM AUTHOR]

Sequence stratigraphic analysis of four widely spaced outcrops of middle Cenomanian to middle Turonian strata deposited in the Western Interior foreland basin in southern New Mexico, USA, defines ten sequence boundaries in a marine shale-rich interval ca 200 m thick. The majority of sequence boundaries are based on basinward shifts in lithofacies characterized by either a non-Waltherian contact between distal-bar or lower shoreface sandstone and underlying lower offshore shale, or an erosional contact between distal-bar or lower shoreface sandstone and underlying upper offshore shale. The sequence boundaries commonly correlate basinward to packages of storm-deposited sandstone and to beds of sandy grainstone composed of winnowed inoceramid shell fragments. In several cases, however, the sequence boundaries pass basinward into presumably conformable successions of lower offshore shale. Maximum flooding surfaces within the sequences are represented by one or more beds of locally phosphatized globiginerid wackestone and packstone or exist within a conformable succession of lower offshore shale. Following initial south/south-westward transgression into the study area, the regional trend of palaeoeshorelines was north-west to south-east, although isopach data indicate that lobes of sandstone periodically spread south-eastward across the study area. The ten sequences in the study area are arranged into a third-order composite megasequence that is characterized by overall upward-deepening followed by upward-shallowing of sequences. The composite megasequence is similar but not identical to the previously established T-1 transgression and R-1 regression in New Mexico. Based on radioisotopic dates of bentonites, the average frequency of the sequences within the study area was ca 327 kyr, which is consistent with fourth-order cycles of ca 400 kyr interpreted in coeval marine strata elsewhere in the world. [ABSTRACT FROM AUTHOR]

Dynamic evolution of the Campanian and Maastrichtian (Upper Cretaceous) of the Miechow 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. [ABSTRACT FROM AUTHOR]

Rich assemblages of dinoflagellate cysts from two sections in the Norwegian Sea provide a solid basis for a palynostratigraphic framework for the upper Albian to upper Maastrichtian succession in this area. The framework is based on a unique composite section combining samples from the shallow stratigraphic core 6711/4-U-1 and core-samples from well 6707/10-1, the latter filling in data from the intervals represented by hiatuses in core 6711/4-U-1. Seven previously described, and one new palynostratigraphic zone, are recognised. These are based on the relative abundances of prominent taxa together with top and base occurrences of selected age-diagnostic dinoflagellate cyst taxa. The zones and their ages in ascending order from the oldest to youngest comprise: the intra late Albian to intra early Cenomanian Subtilisphaera kalaalliti Interval Zone sensu Nøhr-Hansen (1993a); the intra early Cenomanian to intra late Cenomanian Palaeohystrichophora infusorioides – Palaeohystrichophora palaeoinfusa Interval Zone sensu Radmacher et al. (2014b); the Turonian to ?intra early Coniacian Heterosphaeridium difficile Interval Zone sensu Nøhr-Hansen (2012); the ?intra early Coniacian to late Santonian Dinopterygium alatum Interval Zone sensu Radmacher et al. (2014b); the early Campanian Palaeoglenodinium cretaceum Interval Zone sensu Radmacher et al. (2014b); the new intra Campanian Hystrichosphaeridium dowlingii – Heterosphaeridium spp. Interval Zone; the intra late Campanian Chatangiella bondarenkoi Interval Zone sensu Radmacher et al. (2014b) and the intra late Maastrichtian Wodehouseia spinata Range Zone sensu Nøhr-Hansen (1996). Comparison of the palynological events with records in adjacent regions enables correlation across similar paleolatitudes in the Northern Hemisphere. [ABSTRACT FROM AUTHOR]

Palynological investigation of the Upper Cretaceous–lower Paleocene succession from the Tahar section near Arba Ayacha in northwestern Morocco (westernmost External Rif Chain) reveals the presence of rich, diverse and well-preserved dinoflagellate cyst assemblages. For the first time in the study region, biostratigraphic interpretations based on the dinoflagellate cyst assemblages from the studied interval allow the recognition of the upper Maastrichtian and Danian. Relevant upper Maastrichtian–Danian global dinoflagellate cyst events include: the First Appearance Datum of the upper Maastrichtian species Disphaerogena carposphaeropsis , Glaphyrocysta perforata , and Manumiella seelandica ; the Last Appearance Datum of the Cretaceous taxa Dinogymnium spp., Isabelidinium cooksoniae , and Pterodinium cretaceum ; and the First Appearance Datum of the earliest Danian markers Carpatella cornuta , Damassadinium californicum , Membranilarnacia ? tenella , and Senoniasphaera inornata . We formally describe the biostratigraphical range and potential of two new dinoflagellate cyst species, namely Nematosphaeropsis silsila Guédé and Slimani nov. sp., and Pterodinium ayachensis Guédé and Slimani nov. sp. Both species are found in the westernmost External Rif Chain and are restricted to the upper Maastrichtian. [ABSTRACT FROM AUTHOR]

Highlights: [•] Taxonomic (species level) diversity of Madagascan ammonites is much lower than previously supposed. [•] Madagascan inoceramids are quite distinct. [•] Madagascan ammonites demonstrate increasing provinciality with time. [•] Madagascan inoceramids do not demonstrate any stable biogeographic pattern. [Copyright &y& Elsevier]

The statistical and probabilistic analyses of a database of Upper Cretaceous tropical dinoflagellate cysts from Venezuela allow us to recognize 21 species in the optimal stratigraphic sequence. Compilation of the dinoflagellate cysts reported in ten studies of Upper Cretaceous tropical localities from northern South America and the Gulf of Guinea allow the recognition of a rich assemblage (262 species), dominated by gonyaulacoid (129 spp), followed by protoperidinioid (82 spp), areoligeroid (29 spp), gymnodinioid (12 spp) and ceratioid (10 spp) taxa. Seventy-three species in the tropical database are reported in both regions, allowing the age calibration of the optimal sequence from Venezuela. The proposed final sequence of bioevents allows recognition of most stages in tropical Upper Cretaceous strata. The high diversity of the Spiniferites-Achomosphaera group and scarcity of Impagidinium indicates shallow marine depositional environments for most of the Upper Cretaceous tropical localities included. The dominance of gonyaulacoid species in the tropical database suggests that these were the dominant primary producers in the tropical Late Cretaceous oceans. • Statistically valid sequence of dinoflagellate events in Upper Cretaceous, tropical localities. • Sequence effective in northern South America and Gulf of Guinea. • Upper Cretaceous tropical dinoflagellate assemblages led by gonyaulacoid shallow-water taxa. [ABSTRACT FROM AUTHOR]

Biostratigraphic analysis is an essential element for understanding global tectonics and the evolution of life on Earth. Quantitative analysis of sedimentary sequences provides the precise age constraints on timing of significant events in Earth's history. This paper presents results from quantitative stratigraphic analysis of Upper Cretaceous Tethyan Himalayan sequences. This analysis resulted in a new composite stratigraphic section for the Cretaceous strata of Tibet (TIBETKCS). The eight Upper Cretaceous sections were analyzed in this study and 12 planktonic foraminifera zones were recognized based on available data. Quantitative measurements were made using a Graphic Correlation with Graphcor 3.0 software and correlated to the world standard Cretaceous Composite Section (MIDKCS). The sections were also examined using Constrained Optimization software by CONOP9. Level Penalty was applied as the rule to measure misfit among automatically correlated sections. The new TIBETKCS correlates well with planktonic foraminifera ages from previous work in southern Tibet. A fitting equation of y=−0.19 x+305 with a correlation coefficient of 0.94 was obtained from this work The ages of the first and last appearances of 64 planktonic foraminifera can be calculated with this equation with ± 0.3 Ma precision. This level of precision is approximately 10 times higher than age determinations with traditional methods. Two extinction events were resolved within this analysis at ∼93.5 Ma and ∼85.5 Ma corresponding to the Ocean Anoxic Events at Cenomanian-Turonian and Coniacian-Santonian boundaries respectively. [ABSTRACT FROM AUTHOR]