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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).

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.

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 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.

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.

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.

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.

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.