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The Upper Cretaceous Postalm section in the Northern Calcareous Alps (Austria) exposes pelagic deposits of the northwestern Tethys whose cyclostratigraphy and palaeoenvironments were examined in this study. The section displays rhythmic deposits of Santonian to late Campanian age (Gosau Group). The Santonian/Campanian transition is characterised by condensed greyish carbonates, while the younger deposits are composed of reddish foraminiferal packstones displaying distinct limestone-marl alternations. A biostratigraphic framework based on planktonic foraminifera and calcareous nannofossils is supported by carbon and strontium isotope stratigraphy as well as magnetostratigraphy. The carbon isotope data allow to correlate the Postalm section to other Tethyan reference sites and to identify δ13C events, such as the Late Campanian Event. Spectral analyses of three independently assessed proxies (δ13C, Fe content and the thickness of limestone/marl couplets) in the upper, continuously exposed section part identified 17 to 18 405 ka cycles spanning the mid to upper Campanian (Contusotruncana plummerae to Gansserina gansseri Zones or CC21/UC15c to CC23a/UC16 nannofossil zones).

Integrated lithostratigraphic and biostratigraphic data of two well-exposed Maastrichtian–Paleocene successions, namely, the Owina and the Abu Minqar sections (Dakhla Oasis, Western Desert, Egypt), led to enhance the age resolution and shed lights on the paleoenvironmental conditions throughout the deposition of the investigated sequences. The integrated biostratigraphic data provide eight calcareous planktonic zones (five planktonic foraminifera, and three calcareous nannofossil zones) cover the studied interval. The paleoenvironmental setting of the Maastrichtian interval which represented by the lower Kharga Shale unit (Micula murus and Gansserina gansseri calcareous plankton zones) reveals shallow marine environmental conditions of inner neritic probably of marginal setting with high organic matter influx and low-oxygen level interrupted by some transgressive phases. While, shallower marine conditions associated with a sea-level drop mark the Cretaceous/Paleogene (K/Pg) boundary. The lowermost part of the Paleocene interval (NP3, NP4, P1b, P1c, and P2 calcareous plankton zones) which covered the lower part of the upper Kharga Shale unit is marked by middle-outer neritic depositional setting, well-oxygenated seawater, as well as a low organic matter influx coupled with relative sea-level rise. Above this level until reach the base of the Tarawan Formation, a major drop in the sea-level is observed. This interval is marked by absence of the calcareous planktonic taxa. Only agglutinated foraminiferal taxa are recorded during this interval. While the Tarawan Formation (P4b planktonic foraminiferal Zone) is marked by outer neritic depositional setting that represents a sea-level transgressive phase. According to the field observations and the presence/absence of the calcareous planktonic zonal marker species; two tectonic events are detected. The tectonic event I took place at the K/Pg boundary and resulted in a significant hiatus at the studied area. Tectonic event II is observed at the contact between the Dakhla and the Tarawan formations across the Danian–Selandian transition. It is evidenced by the existence of an erosive (irregular) surface at the basal part of the Tarawan Formation. These events could be attributed to the echo of the Syrian Arc tectonism which interrupted the global sea-level curve throughout the Maastrichtian–Paleocene time.

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.

To study the Gurpi Formation deposits in Fars area, 230 thin-sections which belong to Well No. 43 have been studied. The Gurpi Formation is 155 m in thickness. Lithology of the Gurpi Formation is mainly composed of thin to medium limestone, argillaceous limestone and shale. Lower boundary of the Gurpi Formation with the Ilam Formation is continuous and its upper boundary with the Pabdeh Formation is disconformity. In biostratigraphy analysis, 14 species belonging to 31 genera of planktonic and benthic foraminifers were identified, and 6 biozones were recognized based on planktonic foraminifera as follow: (1) Globotruncanita elevata Partial range Zone, (2) Globotruncana ventricosa Interval Zone, (3) Radotruncana calcarata Total range Zone, (4) Globotruncanella havanensis Partial range Zone, (5) Globotruncana aegyptiaca Interval range Zone, (6) Gansserina gansseri Interval range Zone. Based on the fossil contents and the identified biozones, the relative age of the Gurpi Formation is Early Campanian–Maastrichtian. Petrographic studies of the Gurpi Formation led to recognition of six facies including five carbonate facies and one shale facies. All facies of the Gurpi Formation belong to the open marine environment, which are deposited in a shelf model. Based on facies analysis and sea level curves, three depositional sequences along with four sequence boundaries due to discontinuities and relative levels of sea level falling were identified. The sequence boundaries at the lower boundary and in the middle part of the Gurpi Formation are type II sequence boundary (SB2). Only the upper boundary of depositional sequence 3 (the boundary between the Gurpi and Pabdeh formations) due to exposure and presence of erosion effects is revealed as a type I sequence boundary (SB1).

Gurpi Formation is an important sedimentary sequence in the Zagros area of southwest Iran. It provides effective cap rock at the top of the Bangestan reservoirs and acts as a possible source for younger hydrocarbon reservoirs. Integrated facies analysis and paleontological study of this formation are presented in two surface sections located on the Samand and Anaran anticlines of Lorestan Province. The formation has mainly composed of 203–298 m of argillaceous limestones with two clean limestone members of “Seymareh” and “Imam Hassan.” In the biostratigraphic part of this study, 51 species related to 16 genera of planktonic foraminifers in the Dareh Vorazan section and 44 species belong to 16 genera of planktonic foraminifera in Pahleh section were distinguished. Accordingly, four biozones have been determined in the Dareh Vorazan and the Pahleh sections which are Globotruncana aegyptiaca, Gansserina gansseri, Contusotruncana contusa, and Abathomphalus mayaroensis. Consequently, the Gurpi Formation has an age of Late Campanian–Late Maastrichtian. The location of the Cretaceous–Paleogene (K-Pg) boundary is detected at the top of this formation. Macroscopic field observations integrated with microscopic studies have resulted in the recognition of four microfacies types that belong to open lagoon, shoal, proximal, and distal open marine environments of shallow inner to deep basinal settings. Depositional facies and environments of studied sections are interpreted in a regional depositional model.

Upper Cretaceous strata at Göynük, northwestern Anatolia, Turkey, provide a geological record of the Campanian–Maastrichtian from the Sakarya Terrane along the active Neotethys margin. Shales and shaly marls with siliciclastic and volcaniclastic intercalations indicate a pelagic palaeoenvironment rich in planktonic and benthonic foraminifera and calcareous nannofossil assemblages. A composite record from the Campanian to the Maastrichtian records nannofossil standard zones UC15c (CC21) to UC20a (CC26) as well as the Globotrunanella havanensis planktonic foraminifera Zone to the Racemiguembelina fructicosa planktonic foraminifera Zone. The complete ‘mid’-Campanian to early Maastrichtian composite section can be correlated to other western Tethyan sections. The Campanian–Maastrichtian boundary is positioned between the first occurrence of the planktonic foraminifera Gansserina gansseri and the last occurrence of the nannofossil Uniplanarius trifidus. Clastic input and higher sedimentation rates constrain regional sea-level lowstands around the late Campanian calcarata Zone and the Campanian–Maastrichtian boundary, corresponding to the Campanian–Maastrichtian boundary event.

Two exposed sections of the Lower/Upper Maastrichtian to Danian at northern and northeastern Farafra Oasis, Western Desert (Egypt) namely, the Farafra–Ain Dalla road and the Ain Maqfi sections have been analyzed for their planktonic and benthonic foraminifera to constrain the biostratigraphy and infer the paleoenvironmental conditions. Lithostratigraphically, the successions of the present study are classified into the Khoman Chalk and the Dakhla Shale. Biostratigraphically, six planktonic foraminiferal zones; Gansserina gansseri, Racemiguembelina powelli and Plummerita reicheli of the Maastrichtian as well as the Praemurica inconstans (P1c), Praemurica uncinata (P2) and Morozovella angulata (P3a) of the Danian are recognized. A detailed quantitative benthonic foraminiferal analysis has been performed and yields a total of 172 identified benthonic foraminiferal species belonging to 62 different genera. The various foraminiferal parameters as well as cluster analysis provide good information about the paleoenvironmental conditions and sea–level fluctuations across the Maastrichtian–Danian transition. The Maastrichtian revealed outer neritic shelf with slightly shallowing conditions recorded only at the Ain Maqfi section, well oxygenated conditions with low organic matter influx coupled with sea–level rise. During the Maastrichtian–Danian transition, a paleoenvironmental shift to inner-shallow middle neritic shelf, low oxygenated conditions with moderate organic matter influx coupled with sea–level fall is interpreted. This transition is characterized by a major hiatus due to absences of Guembelitria cretacea (P0), Parvularugoglobigerina eugubina (Pα), Parasubbotina pseudobulloides (P1a) and Subbotina triloculinoides (P1b) zones and subzones. It is well marked in the field by an irregular contact and conglomeratic phosphatic dolostone bed at the Farafra-Ain Dalla road section while the disconformity surface can be detected by planktonic foraminifera in the Ain Maqfi section. The lowermost Danian is phosphatic argillaceous chalky limestone with intensive reworking. Low oxygen and/or relatively high–moderate organic matter influx within inner–middle neritic shelf paleoenvironmental conditions can be reconstructed for the lowermost Danian associated with a slight increase in sea–level during the Praemurica inconstans (P1c) zone. The uppermost Danian reflected very well oxygenated conditions and/or low organic matter influx in middle–outer neritic shelf conditions associated with sea–level rise during ages of the planktonic foraminiferal zones P2–P3a.

In this paper, we present a biostratigraphic study of the planktonic foraminiferal associations of the Gurpi Formation outcropping in the Bandar Abbas area of the Zagros Belt (SW Iran). Two stratigraphic sections, Kuh-e Khush and Kuh-e Khamir, were logged and sampled, and the identification of the planktonic foraminiferal assemblages has allowed the recognition of eight Cretaceous biozones, namely Dicarinella asymetrica Zone, Globotruncanita elevata-Globotruncana ventricosa Zone, Radotruncana calcarata Zone, Globotruncanella havanensis Zone, Radotruncana calcarata–Globotruncana aegyptiaca Zone, Globotruncana aegyptiaca-Gansserina gansseri Zone, Gansserina gansseri Zone and Contusotruncana contusa-Abathomphalus mayaroensis Zone. This planktonic foraminiferal zonal framework reveals a latest Coniacian to late Maastrichtian age for the deposits of the Gurpi Formation in the two studied sections. The Cenozoic Interval of the studied sections, represented by the Pabdeh Formation, is attributed to the P3–P6a integrated Zone in the Khush section and the P4c Subzone (Acarinina soldadoensis) in the Khamir section. The data show that the Gurpi Formation at the Khamir locality rests disconformably upon the shallow neritic facies of the Ilam Formation, while in the Khush section this formation disconformably overlies the shallow carbonates of the Sarvak Formation. In addition to the in situ biota, reworked microfossils, such as calpionellids, calcareous algae and benthic foraminifera from older Jurassic (Surmeh Formation) and Cretaceous formations (Surgah equivalent, Sarvak, Kazhdumi and Dariyan formations) are recorded within several stratigraphic levels of the Gurpi Formation.

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.

The Upper Cretaceous sediments in the Moghan area, NW Iran, contain diverse planktonic and benthic foraminifera , with a total of 33 genera and 53 species (17 genera and 38 species of planktonic foraminifera and 16 genera and 15 species from benthic foraminifera), which led to the identification of six biozones spanning the middle Campanian to late Maastrichtian . A detailed paleontological study and biostratigraphic zonation of these sequences has been carried out in four surface sections. This study shows that there are two different facies in the Moghan area, based on the faunal content. A deep open marine condition exists in the Molok, Selenchai and Nasirkandi sections. In these sections, Upper Cretaceous sequences have diverse planktonic foraminiferal species including the Globotruncana ventricosa (middle to late Campanian), Globotruncanella havanensis (late Campanian), Globotruncana aegyptiaca (latest Campanian), Gansserina gansseri (latest Campanian to early Maastrichtian), Contusotruncana contusa- Racemiguembelina fructicosa (early to late Maastrichtian) and Abathomphalus mayaroensis (late Maastrichtian) zones. This deep open marine setting grades laterally into shallower marine condition dominated by large benthic foraminifera such as Orbitoides media, Orbitoides gruenbachensis, Orbitoides cf. apiculata, Lepidorbitoides minor, Pseudosiderolites sp., Siderolites praecalcitrapoides, Siderolites aff. calcitrapoides and Siderolites calcitrapoides . This facies is mainly recorded in the Hovay section. A detailed biostratigraphic zonation scheme is presented for the studied sections and correlated with the results of other studies in the Tethyan realm. This is the first biozonation scheme for Upper Cretaceous sequences of the Moghan area that can be used as a basis for ongoing studies in this area and other parts of Tethys basin.

The study of Globotruncanids of the Gurpi Formation at Sepidar anticline in Zagros Mountains led to distinguishing Santonian to Late Maastrichtian biozones. Eight biozones were determined: biozone I (Dicarinella asymmetrica Zone) belongs to Santonian. Biozone II (Globotruncanita elevata Zone), biozone III (Globotruncana ventricosa Zone), biozone IV (Radotruncana calcarata Zone), biozone V (Globotruncana stuarti Zone) and biozone VI (Globotruncanella havanensis Zone) are of the Early to Late Campanian. Biozone VII (Gansserina gansseri Zone) and VIII (Contusotruncana contusa Zone) suggest the latest Campanian to Late Maastrichtian.

The Farokhi Formation is one of the informal Central Iran formations, which is located in the NW Tabas township. The Tabas area is a part of the Central Iran sedimentary basin which is located in the Yazd Province. The Farokhi stratigraphic section is located 7 km northwest from Farokhi village (33°54' 9''N and 54°52'48''E). The Bazyab, Debarso, Haftoman and Choopanan formations are well-exposed in the studied area. In this study, the Farokhi Formation is investigated in the Farokhi stratigraphic section with regard to planktonic foraminifera. The Farokhi Formation is mainly composed of thick-bedded limestones with ammonoids, thin-bedded limestone with silicified echinoids and ichnofossils, marls with nodular cherts, spherical corals and bivalves. Biostratigraphy of the Farokhi Formation at type section has been concentrated in view of planktonic foraminifera. Thickness of this formation is 251 meters. The lower and upper contacts of studied formation with Haftoman and Choopanan formations are respectively conform and inconsistent. In view of late research, it has been identified that 28 planktonic foraminifera species have a place with 9 genera in edge of 6 biozones, for example: 1) Globotruncanita elevata Partial Range Zone. 2) Globotruncana ventricosa Interval Zone. 3) Globotruncanita stuartiformis Partial Range Zone. 4) Globotruncana aegyptiaca Interval Zone. 5) Gansserina gansseri Interval Zone. 6) Contu-sotruncana contusa Interval Zone. Finally based on this research, Early Campanian-Late Maastrichtian ages for the Farokhi Formation at type locality have been determined.

A 250-m-thick sedimentary succession dominated by siliciclastic deposits occurs in the Kąkolowka Structure of the Skole Nappe. The succession was deposited in the inner part of the Skole Basin during the Late Cretaceous. In position and age, it corresponds to the Kropivnik Fucoid Marl of the Wiar Member (a subdivision of the Ropianka Formation), which was comprehensively described in the external part of the Skole Nappe. In this study, the authors provide the first complete data set on the lithological development and biostratigraphy of the Kropivnik Fucoid Marl from the inner part of the Skole Nappe. The results are compared to previous data from the outer part of the Skole Nappe. In the Kropivnik Fucoid Marl of the Kąkolowka Structure, three main heterolithic facies associations are distinguished: shale-sandstone, marl-sandstone and sandstone-shale. The occurrences of hard, platy and soft marls within siliciclastic rocks are typical of the sections studied. The features observed indicate a turbiditic origin of the deposits studied, including the hard, platy marls. The allogenic material of the strata described includes the small, fragile tests of planktonic foraminifera, which were redeposited from the outer parts of the Skole Basin. Particularly large concentrations of planktonic foraminifera were observed in the hard, platy marls. They are less common in the soft marls and shales. In the Zimny Dzial section, a diverse assemblage of benthic and planktonic foraminifera was found. The Kropivnik Fucoid Marl was dated as uppermost Campanian to lowermost Maastrichtian on the basis of planktonic foraminifera, which represent the Gansserina gansseri Zone. The agglutinated foraminiferal assemblages are representative for the lower part of the Rzehakina inclusa Zone and the co-occurrence of the Caudammina gigantean (Geroch) acme with Rzehakina inclusa (Grzybowski) was observed.

During the Cretaceous, vast amounts of marine sediments were deposited along the south-facing active margin of the Eurasia. A stratigraphic section of 91 m was analyzed for planktonic foraminifera (75 samples), with the aim of establishing a refined biostratigraphy of Cenomanian–Campanian deposits in Central Anatolia. A biostratigraphic framework comprising nine biozones was established. In ascending order, the Rotalipora cushmani, Whiteinella archaeocretacea and Helvetoglobotruncana helvetica zones were defined in the uppermost Cenomanian–Turonian interval. The lack of Coniacian index markers suggests the existence of a hiatus for this interval. In the upper part of the section, the Dicarinella asymetrica, Globotruncanita elevata, Contusotruncana plummerae, Globotruncanella havanensis and Globotruncana aegyptiaca zones were identified for the Santonian and Campanian deposits. The presence of Gansserina gansseri, Globotruncanita angulata, G. conica and G. pettersi in the uppermost part of the section shows that the section ends at the base of the Gansserina gansseri Zone, indicating uppermost Campanian. The planktonic foraminifera biozonation framework provides strong evidence for the timing of the depositional history of the active continental margin that developed south of the Pontides. These phases are mainly the formation of olistostromes of pre-Santonian age, following condensed carbonate deposition during the Santonian and finally the switch from forearc deposition to the formation of a thick sequence of siliciclastic succession starting in the Campanian.

The Upper Cretaceous–Paleogene successions are well exposed at the Farafra Oasis, Western Desert, Egypt. The studied succession is distinguished into three formations arranged from base to top: Khoman (Maastrichtian), Dakhla and Tarawan (Paleocene). The identification of foraminiferal association yielded 55 species (28 planktonic and 27 benthonic). Most of them are considered as important biostratigraphical markers, especially in the Tethyan Realm. Based on planktonic foraminifera, nine biozones are differentiated, the Globotruncana aegyptiaca Zone, Gansserina gansseri Zone, Contusotruncana contusa Zone, Parasubbotina pseudobulloides Zone, Subbotina triloculinoides Zone, Praemurica uncinata Zone, Morozovella angulata-Igorina albeari Zone, Igorina albeari - Globanomalina pseudomenardii Zone and Globanomalina pseudomenardii- Acarinina subsphaerica Zone. The Cretaceous/Paleogene boundary (K/P) lies at the boundary between the Khoman and Dakhla formations. The biostratigraphic framework points to the absence of the Abathomphalus mayaroensis Zone of Late Masstrichtian and Guembelitria cretacea (P0) and Parvularugoglobigerina eugubina (Pα) zones of Early Paleocene. Therefore, the K/P boundary starts with the sudden disappearance of all the Cretaceous genera such as Globotruncana, Globotruncanita, Hedbergella Archaeoglobigerina, Heterohelix, Gansserina and Contusotruncana, followed by the appearance of Danian species such as Parasubbotina pseudobulloides (Plummer), Subbotina triloculinoides (Plummer) and Praemurica uncinata (Bolli). An attempt to estimate the paleobathymetry is done based on the investigated foraminiferal assemblages.

The Qutbabad section of the Gurpi, Tarbur and Sachun Formations in the Fars Province (Zagros Basin) has been studied, in order to determinate its microfacies and sequence stratigraphy. On the basis of thin section studies of cores from Qutbabad Well in the Gurpi, Tarbur and Sachun Formations of the Zagros Basin, four main microfacies have been recognized within four stratigraphic sequences deposited during the Campanian to Maastrichtian. Depth and sea level changes were the main controls on the distribution of these microfacies. The microfacies are: Pelagic; Hemi-Pelagic; Outer ramp; and Middle ramp. The lowermost sequence was deposited in the Early Campanian-early Late Campanian and includes wackestone to packestone textures with biozones Globotruncanita elevate and Globotruncana ventricosa representative of the Pelagic, Hemipelagic and Outer (ramp/shelf). The intermediate and uppermost sequences (sequence two, three and four) display well developed deposits formed at the end of the Campanian (Radotruncana calcarata zone and Globotruncanella havanensis zone), beginning of the Maastrichtian (Globotruncana aegyptiaca zone and Gansserina gansseri zone) and the end of the Maastrichtian (Omphalocyclus macroporus - loftusia sp assemblage zone) on the Pelagic, Hemipelagic, Outer and Middle ramp. On the basis of the sequence stratigraphic chart, the transgression of the Upper Cretaceous Sea started from the Early Campanian and continued gradually towards the Early Maastrichtian. Then, until the end of Maastrichtian, has had regression. This resulted that the sequence stratigraphic model of the Campanian- Maastrichtian Gurpi, Tarbur and Sachun Formations has architecture similar to those that have developed from global sea level changes.

Upper Campanian–Maastrichtian sections on the western flank of the Hun Graben in the Western Sirte Basin (WSB) are displaying two major type facies based on the foraminiferal assemblages. The first one indicates open-marine to outer-shelf conditions, and is represented by numerous bathy-pelagic planktonic foraminiferal species referable to the Radotruncana calcarata, Globotruncana aegyptiaca and the lower part of the Gansserina gansseri Zone (all late Campanian).The second type facies indicates an inner-shelf environment and is represented in the middle-upper part of the Gansserina gansseri Zone (early Maastrichtian) and Racemiguembelina fructicosa (late Maastrichtian) dominated by epi-pelagic planktonic and large benthic foraminifers. Large benthic foraminiferal index species Siderolites calcitrapoides Lamarck and Omphalocyclus macroporus (Lamarck) occur in abundance by the middle–late Maastrichtian. Correlation between planktonic foraminiferal zonation and large benthic foraminiferal zonation is given. An open-marine to outer-shelf environment passed into shallower marine conditions during the late Campanian–early Maastrichtian to late Maastrichtian, then a slight deepening and again shallowing is noticed.

The foraminiferal contents of three surface sections [Gebel Tarboul, Wadi Tarfa (WT) and Bir Dakhl (BD) sections] in southern Galala area, North-Eastern Desert, Egypt, have been studied in detail and used in biostratigraphy and chronostratigraphy of the upper Cretaceous–Paleogene successions. Sixty-nine planktonic foraminiferal species belonging to 23 genera have yielded 17 biozones. They are given in ascending order: Globotruncana aegyptiaca Interval Zone (IZ), Gansserina gansseri IZ, Contusotruncana contusa–Racemiguembelina fructicosa IZ, Abathomphalus mayaroensis IZ, P1c, P2, P3, P3a, P3b, P4, P4a, P4b, P4c, P5, E1, E2, E3, E4 and E5. Moreover, local and widespread regional hiatus was detected in the pelagic to hemipelagic sequence during Cretaceous–Paleogene boundary in southern Galala Sub-basin. This hiatus corresponds to the Early Maastrichtian–Early Eocene in Gebel Tarboul, the interval between Late Maastrichtian–Early Paleocene throughout WT sequences and Late Maastrichtian–Late Paleocene in BD se...

The Oued Necham (ON) section (Kalâat Senan, central Tunisia) provides a well-exposed outcrop of a Campanian-Maastrichtian series that consists essentially of chalky limestones (i.e. the Abiod Formation) grading progressively to a marly unit (i.e. the El Haria Formation). The transitional Abiod-El Haria succession comprises a rich hemipelagic-pelagic fauna in the study area, but ammonites (e.g., Pachydiscus neubergicus, the Campanian/Maastrichtian (C/M) boundary index taxon) are scarce to absent, thus preventing the recognition of the standard zones defined for the Tethyan realm. However, the rich planktonic foraminiferal taxa of the El Haria Formation allow us to establish an accurate biostratigraphical scheme. Accordingly, this work presents a high-resolution planktonic foraminiferal biostratigraphy that is characterised by distinct bioevents associated with the reported C/M boundary (i.e. lowest occurrences (LOs) of Rugoglobigerina scotti and Contusotruncana contusa) at the Global Stratotype Section and Point (GSSP) of the Tercis-les-Bains section, south-western France. Based on these zonal markers, the rugoglobigerinids and multiserial heterohelicids are used to define a subzonal scheme spanning the standard Gansserina gansseri Zone, including the Rugoglobigerina rotundata Subzone indicative of the late Campanian and the Rugoglobigerina scotti Subzone and the Planoglobulina acervulinoides Subzone, respectively, indicative of the early Maastrichtian. The abundance of foraminiferal assemblages allowed us to carry out high-resolution quantitative analyses that document a significant climate cooling during the early Maastrichtian intermittent with short-term warming episodes. Thus, opportunist taxa (r strategists, mostly heterohelicids) thrived during the earliest Maastrichtian cooling event, whereas specialist taxa (k strategists, mostly double-keeled) that had dominated the late Campanian assemblages declined gradually without any extinction. Opportunist and specialist taxa fluctuated in opposite phases throughout the early Maastrichtian (LO of Rugoglobigerina scotti ? LO of Abathomphalus mayaroensis), suggesting essentially variations in water temperature. Since surface dwellers dominated the assemblages, they imply continuous sea surface optimal conditions of nutrient supply and water connectivity induced from upwelling currents.

The stratigraphy, sedimentology and syn-depositional tectonic events (SdTEs) of the Upper Cretaceous/Paleogene (K–P) succession at four localities in north Eastern Desert (NED) of Egypt have been studied. These localities are distributed from south-southwest to north-northeast at Gebel Millaha, at North Wadi Qena, at Wadi El Dakhal, and at Saint Paul Monastery. Lithostratigraphically, four rock units have been recorded: Sudr Formation (Campanian–Maastrichtian); Dakhla Formation (Danian–Selandian); Tarawan Formation (Selandian–Thanetian) and Esna Formation (Thanetian–Ypresian). These rock units are not completely represented all over the study area because some of them are absent at certain sites and others have variable thicknesses. Biostratigrapgically, 18 planktonic foraminiferal zones have been recorded. These are in stratigraphic order: Globotruncana ventricosa Zone (Campanian); Gansserina gansseri , Contusotruncana contusa , Recimguembelina fructicosa , Pseudohastigerina hariaensis , Pseudohastigerina palpebra and Plummerita hantkenenoides zones (Maastrichtian); Praemurica incostans , Praemurica uncinata , Morozovella angulata and Praemurica carinata / Igorina albeari zones (Danian); Igorina albeari , Globanomanlina pseudomenradii / Parasubbotina variospira , Acarinina subsphaerica , Acarinina soldadoensis / Globanomanlina pseudomenardii and Morozovella velascoensis zones (Selandian/Thantian); and Acarinina sibaiyaensis , Pseudohastigerina wilcoxensis / Morozovella velascoensis zones (earliest Ypresian). Sedimentologically, four sedimentary facies belts forming southwest gently-dipping slope to basin transect have been detected. They include tidal flats, outer shelf, slumped continental slope and open marine hemipelagic facies. This transect can be subdivided into a stable basin plain plus outer shelf in the extreme southwestern parts; and an unstable slope shelf platform in the northeastern parts. The unstable slope shelf platform is characterized by open marine hemipelagic, fine-grained limestones and fine siliciclastic shales (Sudr, Dakhla, Tarawan and Esna formations). The northeastern parts are marked by little contents of planktonic foraminifera and dolomitized, slumped carbonates, intercalated with basinal facies. Tectonically, four remarkable syn-depositional tectonic events (SdTEs) controlled the evolution of the studied succession. These events took place strongly within the Campanian–Ypresian time interval and were still active till Late Eocene. These events took place at: the Santonian/Campanian (S/C) boundary; the Campanian/Maastrichtian (C/M) boundary; the Cretaceous/Paleogene (K/P) boundary; and the Middle Paleocene–Early Eocene interval. These tectonic events are four pronounced phases in the tectonic history of the Syrian Arc System (SAS), the collision of the Afro-Arabian and Eurasian plates as well as the closure of the Tethys Sea.

The palaeogeographic setting of the studied Ain Medheker section represents an Early Campanian to Early Maastrichtian moderately deep carbonate shelf to distal ramp position with high rates of hemipelagic carbonate production, periodically triggered by mass-flow processes. Syndepositional extensional tectonic processes are confirmed to the Early Campanian. Planktonic foraminifera identified in thin sections and calcareous nannofossils allow the identification of the following biozones: Globotruncanita elevata, Contusotruncana plummerae (replacing former Globotruncana ventricosa Zone), Radotruncana calcarata, Globotruncana falsostuarti , and Gansserina gansseri . The following stable C-isotope events were identified: the Santonian/Campanian boundary Event, the Mid-Campanian Event, and the Late Campanian Event. Together with further four minor isotopic events, they allow for correlation between the western and eastern realms of Tunisia. Frequently occurring turbidites were studied in detail and discussed in comparison with contourites.

The planktic foraminifera of the Chuangde Formation (Upper Cretaceous Oceanic Red Beds, CORBs) as exposed at Tianbadong section, Kangmar, southern Tibet has been firstly studied for a detailed for a detailed biostratigraphy elaboration. A rich and well-preserved planktic foraminifera were recovered from the Chuangde Formation of the Tianbadong section and the Globotruncanita elevata, Globotruncana ventricosa, Radotruncana calcarata, Globotruncanella havanensis, Globotruncana aegyptiaca, Gansserina gansseri and Abathomphalus mayaroensis zones have been recognized. The planktic foraminiferal assemblage points to an early Campanian to Maastrichitian age for the CORBs of the eastern North Tethyan Himalayan sub-belt, which also provides a better understanding of the shifting progress of the Indian Plate to the north and the evolution of the Neotethyan ocean. The lithostratigraphy of the Chuangde Formation of the Tianbadong section comprises two lithological sequences observed in ascending succession: a lower unit (the Shale Member) mainly composed of purple (cherry-red, violet-red) shales with interbedded siltstones and siliceous rocks; and an upper unit (the Limestone Member) of variegated limestones. The strata of the Chuangde Formation in the Tianbadong section are similar to CORBs in other parts of the northern Tethyan Himalaya area of Asia (Gyangze, Sa'gya, Sangdanlin, northern Zanskar, etc.). The fossil contents of the Chuangde Formation in the sections (CORBs) studied provide a means of correlation with the zonation schemes for those of the northern Tethyan Himalayan sub-belt and the Upper Cretaceous of the southern Tethyan Himalayan sub-belt. Paleogeographic reconstruction for the Late Cretaceous indicates that the Upper Cretaceous Chuangde Formation (CORBs) and correlatable strata in northern Zanskar were representative of slope to basinal deposits, which were situated in the northern Tethyan Belt. Correlatable Cretaceous strata in Spiti and Gamba situated in the southern Tethyan Belt in contrast were deposited in shelf environments along the Tethyan Himalayan passive margin. CORBs are most likely formed by the oxidation of Fe(II)-enriched, anoxic deep ocean water near the chemocline that separated the oxic oceanic surface from the anoxic.

The first data on the taxonomic composition and stratigraphic range of the late Campanian planktonic foraminifers encountered in the middle and upper parts of the Moni Formation, southern Cyprus, are reported. Finds of planktonic foraminifers are associated with the bentonitic clay that composes the matrix of the Moni Formation. The planktonic foraminiferal assemblages revealed are very similar to those from the Kannaviou Formation, western Cyprus, but they are more diverse and yield several key species missing in the Kannaviou sediments. The planktonic foraminiferal assemblages discussed are referred to the Globotruncana aegyptiaca Zone and to the lowermost Gansserina gansseri Zone of the upper upper Campanian of the standard scale. The intraregional correlation of the Moni sections, depth of erosion of the upper part of the formation, and its relationship with the Kannaviou Formation have been refined. When subdividing the upper Campanian sediments based on planktonic foraminifers it is suggested that additional datum planes are used, such as the FADs of Globotruncanella citae and Trinitella scotti. For tracing the Campanian-Maastrichtian boundary (GSSP), attention should be paid to the LADs of Globotruncana bulloides and Contusotruncana fornicata and the potential use of Globotruncanita (Elevatotruncana) eolita sp. nov. should be assessed. It is shown that subfamily Archaeoglobigerininae Salaj, 1987, emend. O. Korchagin is the older synonym of subfamily Archaeoglobigerininae Georgescu, 2005. Two poorly known and three new planktonic foraminiferal species are described.

A new chronostratigraphic framework is presented for upper Campanian-Maastrichtian pelagic sediments cored at DSDP/ODP Sites 390A/1049, 1050, and 1052, which were drilled across a 1300-m depth transect on the Blake Nose (subtropical western Atlantic Ocean). The planktonic foraminiferal zonation is based on standard global biozones for this interval, but rare and sporadic occurrence of two zonal biomarkers, Gansserina gansseri and Globotruncana aegyptiaca , precludes reliable identification of the nominate zones for those species. The Pseudoguembelina palpebra Partial-range Zone is defined as a means of subdividing this upper Campanian biostratigraphic interval. Planktonic foraminiferal, calcareous nannofossil and paleomagnetic datums are integrated to construct reliable age-depth curves for each of the Blake Nose drill sites. These age models are largely confirmed by Sr-isotopic data and suggest significant unconformities at various positions within the sections. Compilation of stable isotope datasets for this time interval from the Blake Nose sites reveals no significant shifts in δ 18O and δ 13C at the time of the inoceramid bivalve extinction (now dated as 68.5–68.7 Ma in the Blake Nose sections) and no correlation with proposed Campanian-Maastrichtian glacial intervals. However, benthic warming associated with Deccan volcanism during the late Maastrichtian is supported.

Five sections of the Cardenas and Tabaco formations in east-central Mexico have been analyzed by means of bio-, Sr-isotope, and sequence stratigraphy, in order to evaluate their age as well as the timing of rudist decline. Ammonites [ Pachydiscus (Pachydiscus) neubergicus (Hauer), Sphenodiscus pleurisepta (Conrad), Coahuilites sheltoni Bose] indicate an early Maastrichtian age for the topmost lower member of the Cardenas Formation and planktic foraminifera [e.g., Globotruncanita stuarti (de Lapparent), Archaeoglobigerina cretacea (d’Orbigny), Globotruncanella petaloidea (Gandolfi), Gansserina gansseri (Bolli), Globotruncana linneiana (d’Orbigny)] a late early Maastrichtian age for the middle member corresponding to the foraminiferal zones CF5 and CF6. Sr-isotope stratigraphic data yield an early late Maastrichtian age (66.93 Ma 17 small-scale and 3 large-scale depositional cycles have been identified, which correspond to para- and depositional sequences. The progradational pattern of the large-scale cycles indicates an overall regression trend, which terminated in subaerial exposure of the area, indicated by paleosoils in the red beds of the Tabaco Formation. The correlation of the large-scale cycles with the global sea level charts indicate that eustatic sea level fall caused the regression and led to the exposure during the middle late Maastrichtian. This subaerial exposure resulted in the loss of habitat and thus the disappearance of rudists in east-central Mexico.

Omphalocyclus is an orbitoidal taxon poorly known from the Late Cretaceous benthonic foraminiferal inventory of the Tethyan realm. Apart from its debatable diagnosis only in the late Maastrichtian of western Tethys, the genus has also been discovered in much older beds in association with Orbitoides and Lepidorbitoides having rather primitive developmental stages. The morphometric analysis of A-forms in successive assemblages, ranging in age from (late) Campanian to terminal Maastrichtian, enables the documentation of phylogenetic changes for the first time. The most conspicuous change is found to be the general increase in the size of the embryon, which on average doubles by the end of the Maastrichtian. This trend is followed by the increase in the number of epi-embryonic chamberlets, which is however, not as significant as the former parameter. Omphalocyclus in the stratigraphically lowermost populations has mainly three to four primary epi-embryonic and no accessory epi-embryonic chamberlets. With the introduction of radial stolons, which seems to have taken place in horizons referable to the Gansserina gansseri Zone, only several accessory epi-embryonic chamberlets arise from the tritoconch. Instead, epi-embryonic chamberlets become rather larger in size and they also cover a wider portion of the embryon along its thick outer wall. Considering the suitable change in embryon size, and also some other morphologic features in successive populations, two new species, O. anatoliensis sp. nov. and O. cideensis sp. nov. are erected in late Campanian and late Campanian-early Maastrichtian populations respectively. The most advanced specimens in the late Maastrichtian are attributed to the long-known species O. macroporus [Lamarck, J.B., 1816. Histoire naturelle des animaux sans vertebres, vol. 2. Verdiere, Paris, pp. 1–568]. Thus, a tentative subdivision scheme comprising three successive species, O. anatoliensis – O. cideensis – O. macroporus , is proposed.

We interpret the subsurface distribution pattern of Late Cretaceous sandstone reservoirs in the Ramnad sub-basin within the framework of sequence stratigraphy via biostratigraphic and lithostratigraphic correlation with outcrop sections in the Ariyalur area of the Cauvery basin. The sequence stratigraphic surfaces recognized in outcrop sections can be correlated to subsurface sections by using biostratigraphic datum markers. By this method five 2 nd and 3 rd order sequences can be recognized in outcrops of the Ariyalur area based on sequence boundaries (SB): 1) the top of the Terani Formation (latest Aptian-earliest Albian SB1), 2) the Karai Formation (middle Turonian Marginotruncana sigali Zone SB2), 3) the Anaipadi member of Garudamangalam Formation (late Santonian Dicarinella asymetrica Zone SB3), 4) the Sillakudi Formation (late Campanian Globotruncanita calcarata Zone SB4), 5) the Ottakovil Formation (early late Maastrichtian Gansserina gansseri Zone SB5), and 6) the Kallamedu Formation (late Maastrichtian Abathomphalus mayaroensis Zone SB6). Examination of log profiles of the Koluvur, Ramnad, Perungulam, Chumaitangi, Kanjirangudi, Periapattinam, Ramanavalasai and Uchipuli structures show that sea level lowstands at the end of the middle Turonian, late Santonian and late Maastrichtian are associated with coarser clastic sediments in deeper parts of the basin. This suggests that low sea levels are associated with bypass of coarser clastics in shelf areas and deposition as fan deposits in the deeper parts of the basin. Major sea level falls thus significantly influence the distribution of coarser clastic sediments and the application of sequence stratigraphic concepts aids the understanding of sandstone reservoirs in the Ramnad sub-basin.

In central Chiapas (southeastern Mexico) the last occurrence of inoceramid bivalves was recorded in strata of the predominantly terrigenous Ocozocoautla Formation. The inoceramids are associated with foraminifers of the Gansserina gansseri Zone (Late Campanian to Early Maastrichtian). The described species are: Cataceramus ? cf. barabini (Morton, 1834), Cataceramus ? cf. subcircularis (Meek, 1876), Trochoceramus aff. costaecus (Khalafova, 1966), Trochoceramus nahorianensis (Kociubynskij, 1968), and Trochoceramus tricostatus n. sp. Based on the inoceramid and foraminifer species present, the assemblage is assigned to the Early Maastrichtian. This age is important because at this level most of the typical inoceramids globally disappeared. This is the first report of the genus Trochoceramus in Mexico, which is a good index fossil for the Early Maastrichtian and has a cosmopolitan distribution.

The Upper Cretaceous sequence of the Korkuteli area (Western Taurides) comprises two formations. The Bey Daglari Formation lies at the base and can be divided into two parts. A 600-m-thick neritic lower part is capped with thin, massive, hemipelagic limestones. The Akdag Formation disconformably overlies different stratigraphic levels of the Bey Daglari Formation along a prominent erosional surface and consists of thin-bedded, cherty, pelagic, clayey limestones. Paleogene marls form the base of the Tertiary sequence and disconformably overlie different stratigraphic levels of the Upper Cretaceous succession. This study identifies from thin sections and analyzes the Late Cretaceous planktonic foraminifera. Identification of forty-five species belonging to the genera Contusotruncana , Dicarinella, Gansserina , Globotruncana , Globotruncanella , Globotruncanita, Marginotruncana and Radotruncana has led to the recognition of five biostratigraphic zones, in ascending order: Dicarinella concavata Interval Zone (IZ), Dicarinella asymetrica Total Range Zone (TRZ), Radotruncana calcarata TRZ, Globotruncana falsostuarti Partial Range Zone (PRZ) and Gansserina gansseri IZ, from the Senonian succession of the Bey Daglari autochthon. The Dicarinella concavata IZ and Dicarinella asymetrica TRZ have been identified from the massive hemipelagic limestones of the Bey Daglari Formation and indicate a Coniacian-Santonian age. The Radotruncana calcarata TRZ, Globotruncana falsostuarti PRZ and Gansserina gansseri IZ have been recognized from the pelagic limestones of the Akdag Formation and suggest a late Campanian-early Maastrichtian age. The identified planktonic foraminiferal biozones indicate that the Bey Daglari carbonate platform drowned after the late Turonian; the Upper Cretaceous (Coniacian-early Maastrichtian) pelagic succession includes two stratigraphic gaps in the Korkuteli area corresponding to lower-middle Campanian and upper Maastrichtian. Slight drowning of the platform after the late Turonian may have been related to the regional extension which affected peri-Mediterranean alpine belts. The regional hiatuses in the pelagic succession are also ascribed to the tectonic events, as the Late Cretaceous is a time of great tectonic activity in this critical area of Tethys. Eustatic sea-level changes may have had a secondary effect on the Upper Cretaceous carbonate succession of the Bey Daglari autochthon.

Initial results from scientific drilling in southern coastal Tanzania are described. In a field season in 2003, a total of five sites was drilled (mostly using continuous coring) by the Tanzania Drilling Project for paleoclimate studies. The sediments are predominantly marine clays and claystones deposited in an outer shelf or slope environment and often contain excellently preserved microfossils suitable for geochemical analysis. The studies reported here include summaries of the lithostratigraphy, biostratigraphy (planktonic foraminifers, calcareous nannofossils, benthic foraminifers, and palynology) and organic geochemistry. TDP Site 6 was drilled near Kilwa Masoko (UTM 37L 555752, 9014922), 350 m to the south-east of a previous site, TDP Site 1. The top 59.58 m, which was mostly drilled without coring, consists of an Oligocene clay formation belonging to nannofossil Zone NP23. The rest of the hole, to a total depth of 61.25 m, consists of a fault zone in which the Oligocene sediments are intermixed with middle Eocene clays of planktonic foraminifer Zone E9 and nannofossil Subzone NP15b. TDP Site 7 consists of two holes (Hole TDP7A: UTM 37L 547126, 9030142; Hole TDP7B: UTM 37L 0547130, 9030140) drilled just 5 m apart at Kwamatola, a creek to the south of Kilwa Kivinje. Underneath approximately 20 m of unconsolidated sands and gravels, claystones and siltstones were recovered to a total depth of 128.00 m. The site spans lower Eocene planktonic foraminifer Zones E1, E2 and E3 and nannofossil Subzones NP 9b and NP10. The bottom of Hole TDP7B approaches the Paleocene–Eocene boundary but no unambiguously Paleocene sediments were recovered. TDP Site 8 was drilled to the south-east of Singino Hill (UTM 37L 548033, 9025811). Below a covering of surface gravels, it yielded predominantly dark greenish-grey claystones to a total depth of 22.95 m. The sediments are from the lower Eocene and span the boundary between planktonic foraminifer Zones E3 and E4 and fall within nannofossil Zone NP10. TDP Site 9 was drilled near Nangurukuru junction (UTM 37L 538987, 9027049). It yielded predominantly dark greenish-grey siltstones to a total depth of 88.80 m. Thin siliciclastic beds with trace fossils of the Nereites ichnofacies are common in the lower third of the site. These sediments span the Campanian–Maastrichtian stage boundary and are assigned to the Globotruncanella havanensis to Gansserina gansseri planktonic foraminifer zones and nannofossil Subzones UC15eTP to UC17. TDP Site 10 was drilled to the west of Singino Hill, adjacent to the main Kilwa road (UTM 37L 0541243, 9028791). Below a superficial covering of gravel, it yielded predominantly dark greenish-grey silty claystones to a total depth of 100.80 m. These sediments are assigned to Paleocene planktonic foraminifer Zone P4c–P5 and nannofossil Subzone NP9b. Organic geochemical analyses from all the sites revealed biomarkers of predominantly terrestrial origin and collectively indicate an unusually low degree of thermal maturity for the area, suggesting shallow maximum burial depths. Traces of migrated hydrocarbons were found in TDP Sites 7 and 10.

A group of red beds occurs in the hemipelagic to pelagic Upper Cretaceous succession of southern Tibet. They are composed of red shale, marl and foraminiferal wackestone and packstone, and considered to be deep-marine sediments that accumulated under oxic conditions following an environmental recovery after anoxia in the world's oceans. Abundant planktonic foraminifera occur in them. The Dicarinella asymetrica , Globotruncanita elevata , Globotruncana ventricosa and Globotruncanita calcarata zones are recognized in the Chuangde succession, indicating an age range of late Santonian–middle Campanian. The age of the red beds in the Gyangze and Sagya regions spans the late Santonian–Campanian. In the Gyirong-Saga region the foraminiferal fauna is characterized by the Gansserina gansseri and Abathomphalus mayaroensis zones, indicating a late Campanian–Maastrichtian age. The oceanic, oxic-bottom, depositional environment developed during the Campanian and Maastrichtian period in southern Tibet, but disappeared from east to west following the regression that is thought to have been caused by the collision between the Indian and Asian plates.

The middle–late Campanian was marked by an increase in the bioprovinciality of calcareous microfossil assemblages into distinct Tethyan, Transitional, and Austral Provinces that persisted to the end of the Maastrichtian. The northwestern Australian margin belonged to the Transitional Province and the absence of key Tethyan marker species such as Radotruncana calcarata and Gansserina gansseri has led petroleum companies operating in the area to use the locally developed KCCM integrated calcareous microfossil zonation scheme. The KCCM zonation is a composite scheme comprising calcareous nannofossil (KCN), planktonic foraminiferal (KPF) and benthonic foraminiferal (KBF) zones. This paper presents the definitions and revisions of Zones KCCM8–19, from the highest occurrence (HO) of Aspidolithus parcus constrictus to the lowest occurrence (LO) of Ceratolithoides aculeus, and builds on our previous early–late Maastrichtian study. The presence of a middle–upper Campanian disconformity is confirmed by microfossil evidence from the Vulcan Sub-basin, Exmouth and Wombat plateaus, and the Southern Carnarvon Platform. In the Vulcan Sub-basin and on the Exmouth Plateau (ODP Hole 762C) the hiatus extends from slightly above the LO of common Rugoglobigerina rugosa to above the LO of Quadrum gothicum. On the Wombat Plateau (ODP Hole 761B) it spans from above the LO of Heterohelix semicostata to above the LO of Quadrum gothicum; and in the Southern Carnarvon Platform the disconformity has its longest duration from above the HO of Heterohelix semicostata to above the LO of Quadrum sissinghii. A significant revision of the events which define Zones KCCM18 and 19 was necessary owing to the observation that the LO of Ceratolithoides aculeus occurs below the HOs of Archaeoglobigerina cretacea and Stensioeina granulata incondita and the LO of common Rugoglobigerina rugosa. In the original zonation these events were considered to be coincident.

A precise correlation of Upper Campanian–Maastrichtian (Upper Cretaceous) sections on the western side of the Northern Oman Mountains (Jabals Qarn El Barr, El Aqabah and Malaqet in the United Arab Emirates and Jabal El Rawdah in the Sultanate of Oman), reveals two distinct facies based on microfaunal assemblages. The first indicates open marine conditions, and is represented by the Qarn El Barr section. This yields numerous planktonic foraminiferal species referable to the Globotruncana aegyptiaca (Upper Campanian), Gansserina gansseri (Upper Campanian–Middle Maastrichtian) and Abathomphalus mayaroensis (Upper Maastrichtian) planktonic foraminiferal zones. During the Campanian–Maastrichtian, this open marine environment passed laterally into shallower marine conditions that were characterized by larger foraminiferal species including Loftusia morgani, Orbitoides media, O. apiculata, Omphalocyclus macropora, Lepidorbitoides minor, Sulcoperculina dickersoni, and Siderolites calcitrapoides. This facies is well developed in the Jabal El Aqabah, Jabal El Rawdah and Jabal Malaqet sections. 2003 Elsevier Ltd. All rights reserved.

The lithological and micropaleontological study of samples collected from several boreholes drilled in the Mesozoic deposits of Istria Depression (Black See shelf) allowed the characterization of intersected Cretaceous successions. The Berriasian - Valanginian deposits are terrigenous, represented mainly by sandstones in the lower parts, and clays above. It is impossible to document the presence of Hauterivian-Aptian deposits in the succession. The Albian deposits are still terrigenous (predominantly clays, sometimes with sponge spicules). The Cenomanian transgressive deposits are coarser, and contain Conicorbitolina conica (d'Archiac), Rotalipora cushmani (Morrow) and Hedbergella-Praeglobotruncana sp. The following Turonian?-Campanian-Maastrictian deposits are micritic limestones with planctonic foraminifera in specific successions: Globotruncana cf. elevata (Brotzen), Globotruncana bulloides (Vogler), Globotruncana arca (Cushman), Globotruncana contusa (Cushman), Gansserina sp. For these specific successions the assemblage indicates a Campanian-Maastrictian age. The age of the most underlying deposits could be estimated only by comparisons with published data (B¾ ncil¾ et al., 1997).

Litho- and planktonic foraminiferal biostratigraphical studies were carried out on the Upper Cretaceous-Lower Eocene succession in three measured sections in the Bani Walid area, northwest Libya. The lithostratigraphical investigations led to the recognition of three formations and six members, from base to top: (i) Zmam Formation, which includes: (a) the Lower Tar Marl Member (Late Cretaceous, Maastrichtian); (b) the Upper Tar Member (Early Palaeocene, Danian); and (c) the Had Limestone Member (Middle Palaeocene, Selandian); (ii) Shurafah Formation, which comprise: (a) the Bu Ras Marl Member; and (b) the Galta Chalk Member (Late Palaeocene, Thanetian); and (iii) Beshima Formation (Kheir Member) of Early Eocene (Ypresian) age. Based on the abundance and stratigraphical distribution of the planktonic foraminiferal species, 12 planktonic foraminiferal zones were recognised, from base to top: Globotruncana aegyptiaca, Gansserina gansseri, Abathomphalus mayaroensis and Plummerita hantkeninoides zones of Late Cretaceous (Maastrichtian) age; Parasubbotina pseudobulloides and Praemurica trinidadensis zones of Early Palaeocene (Danian) age; Praemurica uncinata and Morozovella angulat, as well as Igorina pusilla pusilla zones of Middle Palaeocene (Selandian) age; Globanomalina pseudomenardii and Morozovella velascoensis zones of Late Palaeocene (Thanetian) age and Morozovella formosa formosa zone of Early Eocene (Ypresian) age. The litho- and biostratigraphical results show the presence of two hiatuses in the studied sequence. The first is placed at the Late Cretaceous-Early Palaeocene boundary (K/P boundary) and is located within the Zmam Formation, more precisely at the contact between the Lower and Upper Tar Marl Members and is accompanied by a palaeontological gap, indicated by the absence of the earliest Palaeocene Guembelitria cretacea (P0) and Parvularugoglobigerina eugubina zones (P1a). The second one is located between the Late Palaeocene Galta Chalk Member of the Shurafah Formation (Morozovella velascoensis zone) and the Early Eocene Kheir Member of Beshima Formation (Morozovella formosa formosa zone) and is detected by the absence of the Morozovella edgari and Morozovella subbotinae zones, indicating the instability of the study area during Late Cretaceous-Early Eocene times.

Planktonic foraminiferal assemblages from the Late Cretaceous-Early Tertiary sedimentary sequence in Quseir (Hammadat section), Safaga (Wasif section) and Esh El-Mellaha (Esh El-Mellaha section) areas along the Red Sea Coast, provide a database for biostratigraphical subdivisions and marking of faunal changes. Ten planktonic foraminiferal zones were found. There are, from base to top, the Late Cretaceous Globotruncana aegyptiaca and Gansserina gansseri Zones and the Early Tertiary Parasubbotina pseudobulloides, Praemurica trinidadensis, P. uncinata, Morozovella angulata, Igorina pusilla, Globanomalina pseudomenardii, Morozovella velascoensis and M. edgari zones. Two intervals of non-deposition of sediments (hiatuses) in the study areas are recorded, indicating tectonic events. The first hiatus occurred all over the study areas near the Cretaceous/Tertiary boundary. The second hiatus is restricted to the Late Palaeocene of the Safaga area. Two global planktonic foraminiferal faunal turnover events are identified, reflecting major palaeoceanographic changes. The faunal turnover event I occurred near the M. angulata/I. pusilla boundary near the Palaeocene/Eocene boundary. These turnovers are characterised by the appearance and disappearance of species and changes in relative abundance, diversity and richness of species. Oscillation in the mean sea level in the study areas during the Late Cretaceous-Early Tertiary may be related to a true eustatic change in addition to the evidence for local tectonic control.

Late Campanian through Maastrichtian sea-level changes are examined based on lithology, macrofossils and benthic foraminifera at the Elles and El Kef sections in Tunisia. Six major sea-level regressions are identified during the late Campanian (74.4–74.2 Ma, 74.0–72.5 Ma), the Campanian-Maastrichtian transition (72.2–70.3 Ma), early Maastrichtian (69.6–69.3 Ma, 68.9–68.3 Ma), and late Maastrichtian (∼65.5 Ma). Correlation of the Maastrichtian sea-level regressions with the oxygen isotope record of DSDP Site 525 in the middle latitude South Atlantic reveals that they coincide with episodes of high latitude cooling and appear to be of eustatic origin.

WOS: 000079744700007, The Coreklik Member of the Hekimhan Formation crops out in the Hekimhan (Malatya) region of SE Turkey. It includes beds that are rich in planktic and benthic foraminifera, and in calcareous nannoplankton. Eighty-eight rock samples, considered to be representative of the stratigraphic section, were examined. Seventeen species of planktic foraminifera and the Globotruncana ventricosa, Globotruncanita calcarata (Campanian), Globotruncanella havanensis, Globotruncana aegyptiaca, and Gansserina gansseri (Maastrichtian) planktic foraminiferal zones were recognised. Thirty-two calcareous nannoplankton species and the Ceratolithoides aculeus (CC-20), Quadrum sissinghii (CC-21), Quadrum trifidum (CC-22) (Campanian), Tranolithus phacelosus (CC-23) (Late Campanian-Early Maastrichtian), Reinhardites levis (CC-24), Arkhangelskiella cymbiformis (CC-25), and Lithraphidites quadratus (Early-Late Maastrichtian) zones were identified. Analyses of the sediments, the distribution of planktic and benthic foraminifera and calcareous nannoplankton, the sea-surface palaeotemperature values and palaeosalinity levels respectively calculated from delta(18)O parts per thousand (PDB) and delta(13)C parts per thousand (PDB) isotope Values obtained from globotruncanid tests, and the abundance and diversity of temperature-sensitive calcareous nannoplankton groups allowed the following conclusions to be drawn. (1) Maximum phytoplankton abundances and highest sea level were reached during the Early Campanian; (2) both the numbers of phytoplankton and the sea level began to fall from the Late Campanian onwards, reaching their lowest levels during the Late Maastrichtian; and (3) sea-surface temperature values were stable through the Campanian-Early Maastrichtian but began to fall slowly and intermittently from the end of Early Maastrichtian, reaching minimum values during the Late Maastrichtian. (C) 1999 Academic Press.

Stratigraphic, faunal and isotopic analyses of the Maastrichtian at DSDP sites 525A and 21 in the South Atlantic reveal a planktic foraminiferal fauna characterized by two major events, an early late Maastrichtian diversification and end-Maastrichtian mass extinction. Both events are accompanied by major changes in climate and productivity. The diversification event which occurred in two steps between 70.5 and 69.1 Ma increased species richness by a total of 43% and coincided with the onset of major cooling in surface and bottom waters and increased surface productivity. The onset of the terminal decline in Maastrichtian species richness began at 67.5 Ma and the first significant decline in surface productivity occurred at 66.2 Ma, coincident maximum cooling to 13°C in surface waters and the reduction of the surface-to-deep temperature gradient to less than 5°C. Major climatic and moderate productivity changes mark the mass extinction and the last 500 kyr of the Maastrichtian. Between 200 and 400 kyr before the KT boundary surface and deep waters warmed rapidly by 3–4°C and cooled again during the last 100 kyr of the Maastrichtian. Surface productivity decreased only moderately across the KT boundary. Species richness began to decline during the late Maastrichtian cooling and by KT boundary time, the mass extinction had claimed 66% of the species. Viewed within the context of Maastrichtian climate and productivity changes, the KT mass extinction could have resulted from extreme environmental stress even without the addition of an extraterrestrial impact.

Surface and subsurface Cretaceous sediments in the Ain El-Wadi area, NNE Farafra Oasis have yielded diverse assemblages of palynofloras and foraminifera. The succesion is composed of siliciclastic sediments of the El-Hefhuf Formation which are unconformably overlain by carbonates of the Khoman Formation. Terrestrial palynomorphs are the predominant constituents of the El-Hefhuf Formation in the Ain El-Wadi borehole which is dated as late Turonian-Santonian on the basis of the presence ofArecipitesspp.,Droseridites senonicus,Foveotricolpitesgiganteus,F. cf. gigantoreticulatus,F.cf. tienabaensis, Liliaciditesspp.,Scabratriporites simpliformisand other triporate and tricolporate pollen. One new pollen species,Liliacidites farafraensissp. nov., is described. Deposition of the El-Hefhuf Formation took place in a swamp or marsh environment under the influence of marine incursions for short periods. The white chalk of the Khoman Formation exposed in the Ain El-Khadra section is dated as middle to latest middle Maastrichtian (Gansserina gansseriandContusotruncana contusaforaminiferal Zones). An open marine, warm Tethyan outer shelf environment of deposition is inferred.

"During the early Maastrichtian an assemblage rich in large foraminifera, mostly composed of orbitoidal foraminifera, developed in the shallow-water deposits of the Cárdenas Formation (Valles–San Luis Potosí Platform, Mexico). Among them, the most abundant is Lepidorbitoides minima, some of which display a morphologically abnormal test consisting of polyvalent forms, conical tests and budding, which could be induced by abrupt changes in environmental factors. The occurrence of the abnormalities preceded the demise of this species and of all the larger foraminiferal association in the upper part of the Gansserina gansseri Zone (early Maastrichtian). The abnormalities could be induced by environmental stress, probably related to interplay of different events such as increased terrigenous input and the transition to deeper facies due to Laramide tectonic instability before the K/P boundary. A late Maastrichtian community of dwarfed planktic foraminifera composed of Trinitella scotti Brönnimann, Plummerita reicheli Brönnimann, Rugoglobigerina cf. macrocephala Brönnimann, Rugoglobigerina hexacamerata Brönnimann, Heterohelix punctulata (Cushman), Pseudoguembelina costulata (Cushman), Pseudotextularia intermedia de Klasz, Globigerinelloides asperus Bolli, Guembelitria cretacea Cushman, Rugoglobigerina rugosa (Plummer), Rugotruncana sp., Globotruncanita stuarti (de Lapparent), and Globotruncana arca (Cushman) developed in the upper part of the sequence. This uncommon morphology could also be related to the highly stressed paleoenvironmental conditions related to global climatic change and local tectonic activity. Associated with this planktic assemblage is a deeper-water dwarfed benthic foraminiferal community composed of Gyroidinoides nitidus (Reuss), Coryphostoma incrassata (Reuss), Pseudouvigerina plummerae Cushman, P. cretacea Cushman, Bolivina cretosa Cushman, Planulina texana Cushman and Cibicides harperi (Sandidge)."

There is good evidence that high sea-levels peaked simultaneously during the Late Albian to Turonian in the USA and northwest Europe. Therefore, it is to be expected that the principal peaks during the Campanian-Maastrichtian, now well dated in northwest Europe, should be detectable in the USA. Of the four main peaks in Europe, no. 3, low in the Zone of Belemnitella langei , is the most prominent, and can be recognized with confidence in the Western Interior, New Jersey, Alabama-Mississippi and probably in Texas. The other peaks can be identified with various degrees of confidence, but the sea did not persist long enough in the Western Interior for the last peak, early in the Late Maastrichtian, to be developed there. The results change the generally assumed position of the Campanian-Maastrichtian boundary on the foraminiferal scale: the base of the Maastrichtian on the belemnite scale is a considerable distance above the top of the Zone of Globotruncanita calcarata , possibly as high as the base of the Zone of Gansserina gansseri in north temperate regions. On the ammonite scale in the western interior of the USA the boundary is probably at the base of the Zone of Baculites baculus at 70.7 Ma, but could be at the base of the Zone of B. eliasi .

[1] The lengthy warm, stable climate of the Cretaceous terminated in the Campanian with a cooling trend, interrupted in the early and latest Maastrichtian by two events of global warming, at ∼70–68 Ma and at 65.78–65.57 Ma. These climatic oscillations had a profound effect on pelagic ecosystems, especially on planktic foraminiferal populations. Here we compare biotic responses in the tropical-subtropical (Tethyan) open ocean and mesotrophic (Zin Valley, Israel) and oligotrophic (Tunisia) slopes, which correlate directly with global warming and cooling. The two warming events coincide with blooms of Guembelitria, an extreme opportunist genus best known as the main survivor of the Cretaceous-Paleogene (K-Pg) catastrophe. In the Maastrichtian, Guembelitria bloomed in the uppermost surface water above shelf and slope environments but failed to reach the open ocean as it did at K-Pg. The coldest interval of the late Maastrichtian (∼68–65.78 Ma) is marked by an acme of the otherwise rare species Gansserina gansseri, a deep-dwelling keeled globotruncanid. The G. gansseri acme event can be traced from the deep ocean even onto the Tethyan slope, marking copious production and circulation of cold intermediate water. This acme is abruptly terminated by extinction of the species, a dramatic reversal attributed to a short-term global warming episode. This extinction corresponds precisely with the second bloom of Guembelitria that began ∼300 kyr prior to the K-Pg event. The antithetical relationship between blooming of Guembelitria and the G. gansseri acme reflects planktic foraminiferal sensitivity to warm-cool-warm-cool climatic oscillations marking the end of the Cretaceous.

The two most commonly used biostratigraphic standards for the Campanian–Maastrichtian boundary are the appearance of the belemniteBelemnella lanceolata(Schlotheim) and the disappearance of the planktic foraminiferanGlobotruncanita calcarata(Cushman). The first is a boreal standard, the second tethyan. The assumption that the two coincide is false. In Mississippi the disappearance ofG. calcaratais the same eustatic peak of sea-level which in north Germany lies near the top of theNostoceras polyplocumZone, within boreal nannofossil Zone CC/B22. This places the foraminiferal standard somewhere between 1.3 and 3.5 m.y. older than the belemnite standard. The belemnite standard is at or close to the appearance ofGansserina gansseri(Bolli) in Mississippi.

Planktonic foraminifer distributions in seventeen stratigraphic sections of Upper Cretaceous hemipelagic and pelagic sequences of northern Bey Daglan Autochthon (western Taurides) yield six biozones such as, Dicarinella concavata Interval Zone, Dicarinella asymetrica Range Zone. Radotruncana calcarata Range Zone, Globotruncana falsostuarti Partial Range Zone, Gansserina gansseri Interval Zone, and Abathompholus mayaroensis Concurrent Range Zone. Two of the zones, Dicarinella concavata Zone and Dicarinella asymetrica Zone, are identified in the massive hemipelagic limestones of the Bey Daglan Formation, of Coniacian-Santonian age. They are characterized by scarce planktonic foraminifera and abundant calcisphaerulids. The other four biozones are determined from the cherty pelagic limestones of the Akdag Formation and indicate a late Campanian-late Maastrichtian time interval. The planktonic foraminifera observed in these four biozones are diverse, complex morphotypes (K-selection), suggesting open oceans. The assemblage of the Abathomphalus mayaroensis Zone shows that the latest Maastrichtian record is absent throughout the northern part of the autochthon. Two main sedimentary hiatuses are recognized within the Upper Cretaceous pelagic sequence. Early to middle Campanian and latest Maastrichtian-middle Paleocene planktonic foraminifera are absent in all measured stratigraphic sections. Hiatus durations differ between sections as a result of diachronism of onset of the hemipelagic and pelagic deposition and the post-Santonian and post-Maastrichtian erosional phases. Drowning event and the early-middle Campanian and latest Maastrichtian-middle Paleocene hiatuses in the pelagic sequence are attributed to regional tectonics during the Late Cretaceous. (C) 2009 Elsevier Ltd. All rights reserved.

The study of planktonic foraminifera of the Gurpi formations at Lar area (Kuh-e-kurdeh section) enables me to find the most standard biozones defined in mediterranean regions, especially Tethysian domain. Five biozones were determined. Biozones I (Globotruncanita elevata zone) and II (Globotruncana ventricosa zone) and III (Radotruncana calcarata zone) indicate the Early Campanian and Middle and Late Campanian, respectively. Biozones IV (Globotruncanita stuarti zone) and V (Gansserina gansseri zone) suggest the Early and Middle Maastrichtian, respectively. In the Late Maastrichtian, due to decreasing in water depth at the study area, Abathomphalus mayaroensis zone defined in Tethysian domain was not recognised.

Remarkably thick sequences of upper Cretaceous and lower Tertiary sediments outcrop on the northern coast of the Basque country. We have sampled the well exposed section along the Sopelana beach over 150 m, spanning roughly from middle Maastrichtian (71 Ma) to lower Paleocene (66 Ma), for both biostratigraphic and magnetostratigraphic studies. Thermal demagnetization of ∼ 400 specimens revealed both normal and reversed recent overprints unblocked below 200°C, and both normal and reversed characteristic directions at higher temperatures (200–450°C in the grey limestones; 350–550°C in the redder marls and limestones). Thermal and AF demagnetization and monitoring of weak field susceptibility are consistent with some form of (titano-) magnetite as the main carrier of magnetization. 259 demagnetization diagrams yielded two nearly antipodal clusters of directions, which are still polluted by some 20% remaining recent overprint. The overall mean direction in stratigraphic coordinates is D = 356°, I = 51° (α = 3°), consistent with what is expected for Eurasia at KTB time. Magnetic stratigraphy outlines a succession of eight polarity intervals and is rather straightforward, except for two highly complex zones (52 to 40 m, and 28 to 26 m below the KTB) where the magnetic polarity appears to flip at an unreasonable rate. Biostratigraphic check allows unambiguous assignment of several chrons, with the recognition of the Gansserina gansseri, Abathomphalus mayaroensis, “Globigerina” eugubina, Eoglobigerina edita ( = E. pseudobulloides) and E. trinidadensis zones. The magnetostratigraphic section therefore begins in chron 31R and ends in 29N. Further detailed study of the complex zones reveals that specimens there have a distinct magnetic behaviour: susceptibility increases beyond 400°C, indicating instability and mineralogical change, intensities are higher than elsewhere and more scattered, and a higher unblocking temperature/higher coercivity magnetic component is uncovered. This component, which is absent from the rest of the section, could be an early chemical remagnetization. Indeed the complex zones contain larger amounts of chlorite, a sign of more intense diagenesis. We have therefore discarded samples showing this anomalous behaviour, and have retained only the 223 samples where demagnetization was achieved by 450°C. The thicker, lower complex zone reduces to a reversed chron which we propose to correlate with 30R. We have identified an extra short reversed event within chron 30N, for which independent support is found in DSDP Sites 524 and 577a, and possibly in Gubbio. Finally, the high-sedimentation rate section at Sopelana (25 m/Ma in the Maastrichtian, 7 m/Ma in the Danian) displays one of the best resolved on-land magnetostratigraphies around KTB time. The two complex zones of early remagnetization form an “echo” which may have been generated some 100 kyr after deposition of the sediments. The KTB itself occurs approximately halfway to 3/5 up 29R in terms of time.

The type section of the Upper Cretaceous (Maastrichtian) Tarbur Formation (692 m thick) was defined by James and Wynd (1965, AAPG Bulletin, v., 49, p. 2218) in the paper: Stratigraphic nomenclature of Iranian oil consortium agreement area. We have revised the definition based on field observation and thin section studies. Above the Tarbur Formation, we did not recognize the previously defined Sachun Formation, consisting of red and green marls. Instead we found the upper boundary of the Tarbur Formation to be bounded by a fault, which renders it indistinguishable from the Sachun Formation. Accordingly we propose a new type section for the Tarbur Formation in Kuh-e-Chel Cheshmeh, Kherameh, southeast of Shiraz city. Our study also recognized that marls with pelagic facies that yielded abundant planktonic foraminifera (Gansserina gansseri- Contusotruncana contusa subzone) are Mid-Maastrichtian in age. These marls may occur as a tongue followed by alternating marls and limestones, and finally by a thick-to-massive rudist reefal limestone (34 m thick).