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A hemipelagic succession 29m thick, situated in South Tibet within the Tethyan Himalaya tectonic unit, has been investigated for its calcareous nannofossil content. A total of 17 samples were subject to qualitative and semi-quantitative analysis. The studied interval belongs to the upper Albian-lowermost Cenomanian and extends into the UC0 nannofossil zone; based on the last occurrence of Hayesites albiensis, the UC0a and UC0b-c subzones were recognized. The most abundant nannofossil of the Youxia section is Watznaueria barnesiae. Other common taxa are Eiffellithus turriseiffelii, Eprolithus floralis, Rhagodiscus spp., and Zeugrhabdotus spp. In the lowermost part of the studied section, below the beginning of the Albian-Cenomanian Boundary Event (ACBE), i.e., prior to the δ13C positive excursion related to OAE1d, the nannofossils confined to high paleolatitudes, namely Repagulum parvidentatum, Seribiscutum primitivum, and Sollasites horticus, are present with a low abundance. This occurrence is believed to be evidence of a short episode of cooler surface waters linked to a transgressive event. The nannofossil abundance and diversity, along with the fluctuation patterns of the nutrient and temperature indices throughout the section, reflects a primary signal of mesotrophic to eutrophic conditions from the base of the succession up to the two oldest δ13C peaks of ACBE, both late Albian in age and within the OAE1d. By contrast, the dominance of Watznaueria barnesiae, representing more than 80% of the total assemblages, along with the significant drop in abundance and diversity shown by nannofossils within late phases of ACBE, are interpreted as a diagenetic signal. Mesotrophic to eutrophic conditions returned towards the top of the studied succession, where Biscutum constans and Zeugrhabdotus erectus again show a higher abundance.

A hemipelagic succession 29m thick, situated in South Tibet within the Tethyan Himalaya tectonic unit, has been investigated for its calcareous nannofossil content. A total of 17 samples were subject to qualitative and semi-quantitative analysis. The studied interval belongs to the upper Albian-lowermost Cenomanian and extends into the UC0 nannofossil zone; based on the last occurrence of Hayesites albiensis , the UC0a and UC0b-c subzones were recognized. The most abundant nannofossil of the Youxia section is Watznaueria barnesiae. Other common taxa are Eiffellithus turriseiffelii , Eprolithus floralis, Rhagodiscus spp., and Zeugrhabdotus spp. In the lowermost part of the studied section, below the beginning of the Albian-Cenomanian Boundary Event (ACBE), i.e., prior to the δ13C positive excursion related to OAE1d, the nannofossils confined to high paleolatitudes, namely Repagulum parvidentatum , Seribiscutum primitivum , and Sollasites horticus , are present with a low abundance. This occurrence is believed to be evidence of a short episode of cooler surface waters linked to a transgressive event. The nannofossil abundance and diversity, along with the fluctuation patterns of the nutrient and temperature indices throughout the section, reflects a primary signal of mesotrophic to eutrophic conditions from the base of the succession up to the two oldest δ13C peaks of ACBE, both late Albian in age and within the OAE1d. By contrast, the dominance of Watznaueria barnesiae , representing more than 80% of the total assemblages, along with the significant drop in abundance and diversity shown by nannofossils within late phases of ACBE, are interpreted as a diagenetic signal. Mesotrophic to eutrophic conditions returned towards the top of the studied succession, where Biscutum constans and Zeugrhabdotus erectus again show a higher abundance. [ABSTRACT FROM AUTHOR]

Two sediment sections are investigated at Cape Arkhangelos, island of Rhodes, where Pleistocene marine sediments crop out in horsts and grabens of a Mesozoic basement. There, hemipelagic sediments characterized by upper bathyal communities are atypically mixed with much shallower faunal components because they were deposited close to rugged coastal landforms. Biostratigraphic analyses show that the sections were deposited between 1.8 and 0.9 Ma, and between 1.8 and 1.6 Ma, respectively. By combining the planktonic/benthic foraminiferal ratio with 31 bathymetric indicators chosen among extant species of benthic foraminifera, mollusks, and bryozoans, we show that relative sea-level fluctuations can be reconstructed in these atypical settings despite the proximity of steep slopes that favored transportation of allochthonous fauna. The shallow-water components (including gravels and calcareous algae) were transported downslope by the combined action of gravity, currents, and tectonic disturbance that promoted drowning (with a maximum flooding recorded at ca. 1.7 Ma) and then uplift of fault-bounded paleovalleys that formed during the Early Pleistocene. Abrupt facies changes and age differences between sections have been triggered by the irregular paleotopography of the Mesozoic basement, which fostered differential depositional settings, with outer to middle neritic deposits above the horsts and upper bathyal deposits in paleovalleys. [ABSTRACT FROM AUTHOR]

This work presents the calcareous nannofossils assemblages identified in samples recovered from 5 boreholes, drilled on the western side of the Olt River, in the Băbeni area. These boreholes crossed the Lower Oligocene-Lower Miocene sedimentary successions. The identified assemblages were included in the following intervals: (i) upper part of NP21 calcareous nannofossil zone to the lower part of NP23 biozone, corresponding to the early Rupelian, (ii) upper part of NP23 biozone up to NP25 biozone, spanning the late Rupelian-Chattian interval, and (iii) NN1 up to NN3 biozones, covering the Aquitanian and Burdigalian stages. The diversity and abundance of the identified nannofossil assemblages allow paleoenvironmental reconstructions. [ABSTRACT FROM AUTHOR]

This study aims to bring new constraints on the Eocene stratigraphy of the northern edge of Istria Basin, located in Western Black Sea. For achieving our goal, we have studied several core reports containing the description of the lithology and microfossils assemblages (foraminifera, ostracods and calcareous nannofossils) from 3 wells drilled in the northern Istria Basin. Thus, we were able to identify lithological and biostratigraphic constraints, allowing to generate a coherent correlation scheme for the Eocene deposits, with precise age assignment and advanced models of the IB evolution during the Eocene. The lithology of the 3 wells, situated in the Sinoe, Lebăda West and Lebăda East areas, is mainly represented by calcareous sandstones and siliciclastic ones. The biostratigraphy indicates that the deposits of the Sinoe and Lebăda West wells are Middle Eocene in age (mostly the upper part), while in the Lebăda East well a late Early to Middle Eocene age was assigned. [ABSTRACT FROM AUTHOR]

Calcareous nannofossil investigations were carried out on successions cropping out in an expanded section situated in the Romanian Carpathians bend area (nearby the Pucheni village, Dâmbovia River basin). Nannofossil biostratigraphy indicates a Santonian - late Maastrichtian age for the investigated deposits. The studied red and variegated sediments are correlated with similar deposits occurring in the bend region of the Romanian Carpathians. [ABSTRACT FROM AUTHOR]

This paper presents investigation carried out on two sections containing successions of the middle Sarmatian s.l. (Bessarabian) and upper Sarmatian s.l. (Khersonian). Both substages are mainly characterized, from lithological point of view, by the presence of chalky limestones, argillaceous limestones, oolithic limestones and coquinas. The boundary between the two substages is marked by coquinas mainly containing small-sized specimens of the bivalve Cardium spp. The upper Bessarabian is characterized by the Plicatiforma fittoni bivalve zone, while in the Khersonian substage the Mactra caspia bivalve zone, followed by Mactra bulgarica biozones are present. The Techirghiol section contains no calcareous nannofossils, while in the Limanu section a few specimens assigned to the genus Noelaerhabdus were discovered in the upper Bessarabian. This finding indicates a possible connection of the South Dobrogea (part of the Euxinian-Caspian domain) with the Central Paratethys, during the middle Sarmatian s.l. (Bessarabian). [ABSTRACT FROM AUTHOR]

The calcareous nannofossil Ceratolithus acutus (= C. armatus ) is an important species associated with the final flooding that ended the Messinian Salinity Crisis in the Mediterranean. We emphasize its robust identifying features and stratigraphic value in the global ocean. This species is particularly useful in recognising and constraining the Messinian–Zanclean boundary in the Mediterranean, as evidenced by reports from 75 localities and 20 references in addition to our own papers. Our emphasis is prompted by the assessment of Stoica et al. (2016) that Ceratolithus acutus is a “dubious” species with its lowest occurrence an “unreliable” biostratigraphic event. Such assessments by non-specialists, especially when “supported” by selective referencing of the literature warrant an explanation. [ABSTRACT FROM AUTHOR]

This study presents detailed foraminiferal, ostracod, and calcareous nannofossil analyses of five Middle Miocene sections located in the Central Paratethyan realm, namely in Poland, Romania and the Republic of Moldova. Based on foraminiferal distribution, five biostratigraphically important assemblages (labelled A-E) are distinguished. Foraminifera data combined with ostracoda and nannofossil evidence allowed correlation between the studied sections, and a comparison with the deposits of similar age from the Transylvanian, Vienna and Pannonian basins, as well as with the Transcarpathian regions. The micropaleontological record across the Badenian-Sarmatian boundary interval is also presented. [ABSTRACT FROM AUTHOR]

An integrated magneto-biostratigraphic study, based on calcareous nannofossils and foraminifers, together with the radiometric dating of a volcaniclastic layer found in several outcrops, was carried out on the hemipelagic deposits of the Lindos Bay Formation (LBF) at six localities on the island of Rhodes (Greece). Our highly refined chronostratigraphic framework indicates that the lower and upper lithostratigraphic boundaries of the LBF are diachronous. Associated with the 40 Ar/ 39 Ar age determination of 1.85 ± 0.08 Ma for the volcaniclastic layer, our data show that among the investigated outcrops, the Lindos Bay type locality section provides the longest record (1.1 Ma) of the LBF. Hemipelagic deposition occurred continuously from the late Gelasian (∼1.9 Ma) to the late Calabrian (∼0.8 Ma), i.e., from Chrons C2n (Olduvai) to C1r.1r (Matuyama) and from nannofossil Zones CNPL7 to CNPL10. This long record, together with the hemipelagic nature of the deposits, make the Lindos Bay type locality section a unique element in the eastern Mediterranean region, allowing future comparisons with other early Quaternary deep-sea sections available in the central and western Mediterranean regions. [ABSTRACT FROM AUTHOR]

Several sites from the NW Black Sea, namely, the Romanian Black Sea shelf, situated at water depths ranging from 17 m to 80 m, have been investigated. The superficial sediments, i.e., the water/sediment interface, were analyzed for their calcareous nannoplankton content. Both quantitative and qualitative nannofloral analyses have been performed. The nannofloral assemblages that are in situ contain only Emiliania huxleyi and Braarudosphaera bigelowii. Offshore, in front of the Danube mouth, only resedimented calcareous nannofossils from older Mesozoic-Tertiary deposits are present. Concerning the nannofloras in situ, the maximum bloom of Emiliania huxleyi in the studied area is placed in the region where the influx in sediments and waters rich in nutrients is significant, due to the input of both the Danube and Dniepr rivers, at a distance exceeding 30-40 km from the coastline. Apart from the coccolithophore algae, other groups of organisms, such as silicoflagellates, diatoms and dinoflagellates, were recorded. Their distribution pattern clearly reflects the marine setting; hence, differences in abundance and diversity between the inner and outer shelves have been observed. [ABSTRACT FROM AUTHOR]

Abstract: This study presents carbon and oxygen isotope fluctuations identified in marine red marlstones and claystones of the Fizeşti Formation from the SE Haţeg area (Southern Carpathians, Romania). Biostratigraphy based on calcareous nannoplankton allow the identification of nannofossil standard zones and subzones CC16–CC17 up to CC20, and respectively UC11c up to UC15b, indicating that the investigated deposits are latest Coniacian–late Early Campanian in age. Throughout the studied succession, δ13C values fluctuate between 1.4‰ and 2.65‰, while δ18O values are between −3‰ and −4‰. In the middle Santonian (within the UC12 calcareous nannofossil zone), we found a slight positive carbon isotope excursion, with values increasing by 0.3‰, up to a value of 2.44‰, which we assume to represent the regional expression of the Horseshoe Bay Event, originally recognized in the English Chalk. In the uppermost Santonian, just below the first occurrence of the crinoid Marsupites testudinarius (within the UC13 calcareous nannofossil zone), we recorded a δ13C increase, from 2.38‰ up to 2.63‰, correlative with the Hawks Brow Event, firstly described in UK. The most significant δ13C increase identified by us, up to 2.63‰, is coincident with the last occurrence of the crinoid Marsupites testudinarius (=the Santonian–Campanian boundary) and represents the regional expression of the worldwide distributed Santonian/Campanian Boundary Event. The Santonian–Campanian boundary is associated with a slight positive excursion for δ18O. In the lower part of the Campanian stage, δ13C values progressively decrease to around 1.5‰. A decrease of the water surface temperature in the region is suggested for the lower part of the Santonian, an assumption based on the significant shift to less negative values of δ18O and on the mixed (Tethyan and Boreal) character of the identified nannofloras. From the Santonian–Campanian boundary interval upwards, the temperatures were rising, leading to an arid and warm climate in the region. This climate mode continued probably into the Maastrichtian, when the Haţeg area became part of an island situated in the Northern Tethys Realm. [Copyright &y& Elsevier]

Abstract: This paper presents the lithological and biostratigraphical (mainly based on calcareous nannofossils) record of the marine sediments which crop out in the NW and SE Haţeg regions. Upper Cretaceous marine deposition starts in these two regions in the Early Cenomanian (both in the CC9 calcareous nannofossil zone, and within UC1–UC2 biozones, respectively). In NW Haţeg, a hemipelagic sequence composed of red shales and marlstones, followed by white marlstones, probably associated with a deep-water paleoenvironment, marked the beginning of Upper Cretaceous marine sedimentation. In the SE, marine deposition started with sandstones and calcarenites, interlayered with Actaeonella and Ytruvia coquina, indicating an infralittoral paleoenvironment. From the Cenomanian up to the Coniacian, the marine setting becomes progressively shallower in the two Upper Cretaceous marine depositional Haţeg areas; this change is marked by the occurrence of outer shelf deposits in the NW and inner shelf sediments up to infralittoral ones in the SE. These deposits are followed by lower Santonian–upper Campanian turbidites in the NW, and by Lower Santonian–Campanian pro parte red marlstones and Upper Campanian turbidites, in the SE. The marine sedimentation ends, in NW Haţeg, with distal turbidites, Late Campanian in age (placed in the CC22 calcareous nannofossil zone, in the UC15d subzone respectively, slightly above the first occurrence of the nannofossil Uniplanarius trifidus). Towards the end of the Campanian, conglomerates and sandstones with Actaeonella and Ytruvia coquina, yielding reworked nannofloras (including Late Campanian taxa), occur in SE Haţeg. Associated with the paroxysmal Laramian tectonic phase, continental deposition started, probably within the Campanian/Maastrichtian boundary interval, both in the NW and SE parts of the Haţeg region. During the Late Cretaceous interval, different paleoenvironmental settings may be distinguished in the NW Haţeg (where a deep marine basin developed for most of the Early Cenomanian up to the Late Campanian interval), and in the SE Haţeg (characterised by an outer oscillating basin with an episodic shallow-water deposition in the same interval). Despite the various backgrounds of the two regions, some common regional events, such as the Early–Middle Cenomanian and the Early Santonian–Early Late Campanian sea level highstand, as well as the Late Cenomanian–Coniacian sea-level lowstand were recognised in both investigated areas. [Copyright &y& Elsevier]

Oceanic Anoxic Events (OAEs) were intervals known to produce conditions that favoured increased organic carbon burial rates. Most of the OAEs took place in mid Cretaceous times that are characterised by a global greenhouse climate. This paper discusses biotical and palaeoenvironmental changes (based on geochemical record) of a short mid Cretaceous OAE, namely OAE1d, produced during the Albian stage. Sections from Eastern Carpathians (Romania) and Tibet (China) were investigated for the calcareous nannofossils events along with 13C and 18O isotopic records. The OAE1d from the Youxia section (Tibet) extends within the nannofossil subzones UC0b–UC0c, containing Albian nannofossil events such as the last occurrence of Hayesites albiensis, followed by successive first occurrences of Gartnerago chiasta and Cylindralithus serratus. A positive excursion of the 13C isotope was identified within this interval, including four sub-events (Yao et al., 2018). Besides, before the beginning of OAE1d, the occurrence of nannofossils more related to cold-water surfaces such as Seribiscutum primitivum, Biscutum constans, Repagulum parvidentatum and Crucicribrum anglicum (Bown et al., 1998; Mutterlose et al., 2009) was recorded, in an interval coincident with the latest Albian transgression (Haq, 2014).Based on isotope and palaeontological records, the OAE1d was identified in the southern part of the Eastern Carpathians bend. The positive shift of isotope 13C is situated in the Stoliczkaia dispar ammonite zone (Melinte-Dobrinescu et al., 2015). The calcareous nannofossil assemblages are scarce, but contain, among other taxa, Eiffellithus monechiae and E. turriseiffelii, indicating a late Albian age. From the nannofossils showing a high-latitude affinity and upwelling conditions, rare Biscutum constans and Seribiscutum salebrosum are present. Spectral analysis of CaCO3 content in the studied successions reveals that the sedimentary record was mainly controlled by eccentricity (~100 kyr) and precession (22.2 kyr). The interval covers by OAE1d is ~233 kyr.ReferencesBown, P.R., Rutledge, D., Crux, J.A., Gallagher, L.T., 1998. Lower Cretaceous. In: Bown, P. R. (Ed.), Calcareous Nannofossil Biostratigraphy. Kluwer Academic, Cambridge University Press, 86–131.Haq, B.U., 2014. Cretaceous eustasy revisited. Global and Planetary Change 113, 44–58Melinte-Dobrinescu, M., Roban, R., Stoica, M. 2015. Palaeoenvironmental changes across the Albian/Cenomanian boundary interval in the Eastern Carpathians. Cretaceous Research 54, 68–85.Mutterlose, J., Bornemann, A., Herrle, J., 2009. The Aptian-Albian cold snap: Evidence for "mid" Cretaceous icehouse interludes. Neues Jahrb. Geol. Paläont. Abh. 252/2, 217–225.Yao, H., Chen, X., Melinte-Dobrinescu, M.C., Wu, H., Liang, H., Weissert, H., 2018. Biostratigraphy, carbon isotopes and cyclostratigraphy of the Albian- Cenomanian transition and Oceanic Anoxic Event 1d in southern Tibet. Palaeogeography, Palaeoclimatology, Palaeoecology 499, 45–55. [ABSTRACT FROM AUTHOR]

Abstract: New field observations and fossil analyses complete and clarify the strong impact of the Mediterranean sea-level changes linked to the peak of the Messinian Salinity Crisis on the Dacic Basin in southwestern Romania. In addition to the Gilbert-type fan delta already evidenced along the Danube River in the area of Turnu Severin, a new Gilbert-type fan delta is described northward. Early Zanclean bottomset beds are evidenced and dated based on nannofossils at the junction of the two coalescing Gilbert-type fan deltas. A clear sedimentological, morphological and chronologic differentiation is established in the area between the Carpathians Late Miocene piedmont alluvial fans and the early Zanclean Gilbert-type fan deltas. The early Zanclean age of the Hinova clays, where the bottomset beds of the Gilbert-type fan deltas are mostly developed, is confirmed by the occurrence of nannofossil markers of Subzone NN12b and a Bosphorian mollusk macrofauna. Early Zanclean inflow of Mediterranean marine waters into the Dacic Basin is also supported by the record of planktonic foraminifers. In the Dacic Basin, the Messinian Salinity Crisis resulted in the cutting of the Iron Gates by a Carpathians river. Fluvial erosion also affected the residual Pannonian Basin and probably catched the paleo-Tisza River which contributed to the erosion of the Iron Gates and to the fluvial drainage of the partly desiccated Dacic Basin. Arguments are reinforced in favor of a marine gateway between the Mediterranean and Dacic Basin through the Balkans before and after the Messinian Salinity Crisis. [Copyright &y& Elsevier]

Submarine canyons are commonly controlled by tectonic structures and, therefore, are key elements of the evolution of convergent margins. The present study focuses on the Southern French Alpine Foreland Basin. Here we use the outcrops of Grès d'Annot Formation and Schistes à Blocs Formation of the Sanguinière-Restefond Sub-basin to study the formation of an ancient canyon in relation to extensive tectonics of the Colombart Structure. The Grès d'Annot Upper Erosion Surface (GAUES) and faults have been mapped in the field and using airborne and drone pictures. Moreover, the planform pattern of the canyon was reconstructed using GIS modelling. Finally, the deposition age of the Schistes à Blocs Formation, which is considered to belong to the Lower Rupelian, has been constrained by the analysis of calcareous nannofossils and benthic foraminifera coming from nine samples. The Colombart Structure is composed of two normal faults of southern vergence bordering a northward dipping rollover anticline, and axially controls the 700 m deep La Bonette Canyon cutting through the underlying Annot Sandstones. The La Bonette Canyon exhibits a succession of sharp erosive features, such as erosive walls, ramps and terraces. The cross-section profile of the La Bonette Canyon exhibits a tectonic control at several scales: it is asymmetric as well as the thalweg is, which is made of an erosive ramp exploiting the underlying structural dip, and an axial incision whose location is controlled by faults. Faults also commonly control smaller scale morphologies, but also the capture of tributaries at right angles with the canyon axis, testifying for a rectangular drainage pattern. The GAUES is interpreted to result from retrogressive erosion and erosion by gravity currents affecting partially lithified turbidites following three main triggering factors which are: i) a possible tilting of the basin towards the west or north-west, and ii) the 3rd order eustatic fall linked to the Oi1a δ18O event, and iii) the increasing erosive power of gravity currents, which were sourced from the remobilized front of the Autapie nappe during its advance in the basin. Tectonic activity and canyon excavation also triggered destabilization of the flanks during deposition of the Schistes à Blocs Formation. • Characterization of an ancient submarine canyon in an Oligocene foreland basin and reconstruction of its planform pattern by combining field observations and GIS modelling. • Asymmetrical cross-section profile of a submarine canyon controlled by syn-sedimentary normal faults and rollover anticline. • Formation of walls, ramps and terraces shaping canyon flanks by retrogressive erosion affecting partially lithified sandstones. • Control on location of walls, ramps and terraces by syn-sedimentary normal faults. • Canyon incision and retrogressive erosion both triggered by basin deformation and eustatic fall. [ABSTRACT FROM AUTHOR]

Sediments deposited after the peak of the Messinian Salinity Crisis (MSC) in the Apennine foredeep of Italy embody a topic debated on both chronostratigraphic and palaeoenvironmental grounds. We performed micropalaeontological (calcareous nannofossil and dinoflagellate cyst) analyses on four stratigraphic sections (Monticino, Civitella del Tronto, Fonte dei Pulcini, Fonte la Casa) and reused those previously published from Maccarone. All sections belong to the p-ev 2 Fm. that includes the Colombacci deposits, usually considered emblematic of the Lago Mare in the area. Marine microfossils recorded in previous studies have often been neglected or considered reworked and hence discarded. We propose the occurrence of at least four marine inflows between 5.36 and 5.33 Ma, the first of which is reflected in the Apennine foredeep by marine dinoflagellates that are then replaced by Paratethyan (brackish) ones. Paratethyan species occupied favourable environments during intervals separating marine inflows while the marine species survived elsewhere. From this perspective, the Apennine foredeep was an isolated perched basin during most of the peak of the MSC (5.60–5.36 Ma), and was progressively and repeatedly invaded by marine waters overflowing a palaeo-sill before the beginning of the Zanclean (5.33 Ma) which itself reflects a continuing eustatic rise. The Gargano Peninsula and, offshore, the present-day Pelagosa sill may be regarded as the remnants of this Messinian sill. This interpretation provides new possibilities for ecostratigraphically correlating the sections with Lago Mare biofacies, the deposition of which unquestionably started prior to the deposition of Colombacci sediments and continued into the earliest Zanclean. The results of this study show that the Lago Mare facies cannot be restricted to a single brackish palaeoenvironment but included competing marine and brackish waters controlled by geographic and chronological factors. Deposits overlying the unconformity separating the regional p-ev 1 and p-ev 2 formations are considered to represent the first marine incursion into the Apennine foredeep. These results allow us to refine the palaeogeographic reconstruction of the Apennine foredeep during the peak of the MSC. Although this basin was deep, its history during the peak of the MSC did not parallel that of the central Mediterranean basins. [ABSTRACT FROM AUTHOR]

New insights into the geodynamic evolution, the paleogeographic framework and the paleoclimatic setting of the Upper Eocene-Oligocene lacustrine basins from South-East France have been provided by an integrative approach combining geochronology, micropaleontology and stable isotope analyses. U Pb dating on calcite, pollen-based climatostratigraphy and strontium and sulfur isotope signatures of sulfates provided a robust chronostratigraphic framework for the Upper Eocene and Oligocene succession from the Vistrenque, Alès and Roussillon basins. The thick Priabonian- lower Rupelian lacustrine succession from the Vistrenque Basin is interpreted to be deposited in a strike-slip basin associated with the latest stages of pyrenean shortening. Floral assemblages are used to reconstruct the vegetation cover in the lacustrine systems and their neighbouring lowlands and highlands. Composition of saltwater inferred from strontium and sulfur isotope signatures of sulfates, the occurrence of calcareous nannofossils, dinoflagellate cysts and pollen grains of mangrove-related plants provided strong evidence for marine intrusions into the Alès Basin during the Priabonian and the Vistrenque Basin during the Rupelian and Chattian. Paleogeographic reconstructions of Southeast France during the Priabonian and late Rupelian strongly suggest marine incursions from the Alpine Sea via two potential pathways: upper Rhône Valley via the Crest Sill and lower Rhône Valley via the Haut-Var Pyrenean synclines. On the other hand, Upper Oligocene evaporite basins in the Camargue area have been subjected to marine intrusions from the Western Mediterranean Sea following the collapse of the eastern pyrenean relief during the Liguro-Provençal rifting stage. Finally, pollen analysis and Climate Amplitude Method revealed a brief but significant stage of cooling and aridification at the very base of the Rupelian which could represent the regional and terrestrial expression of the global climate cooling following the Eocene-Oligocene Transition. • Marine incursions occurred during the Priabonian in the Ales and Saint-Chaptes basins; • Marine incursions are evidenced in the Vistrenque Basin in early Rupelian to Chattian times; • Marine water is sourced from the Alpine Sea during the Priabonian and Rupelian; • Marine water derived from the western Neotethys during the Chattian; • A brief but significant stage of cooling and aridification occurred during the earliest Rupelian; [ABSTRACT FROM AUTHOR]

New data from the Neogene Boudinar and Arbaa Taourirt basins (northeastern Morocco) provide constraints on the late Miocene evolution of the North Rifian Corridor. The chronostratigraphy of these basins is clarified on the basis of biostratigraphic (planktonic foraminifers, calcareous nannoplankton) and radio-isotope ages. Marine sedimentation in the Boudinar Basin began during the early Tortonian at ~ 10 Ma and persisted until the late-early Messinian at ~ 6.1 Ma. In the Arbaa Taourirt basin, it occurred between the late Tortonian and the earliest Messinian. Paleoenvironmental data (benthic foraminifera and pollen grains) record a major drowning in association with extensive tectonism in the Boudinar basin during the early Messinian (~ 7.2 Ma). Synchronously, there was a major sedimentological change in the Arbaa Taourirt basin with progradation of conglomerates and sandstones over late Tortonian marls. Large-scale cross-bedded sandstones indicate paleo-currents flowing from the Atlantic Ocean toward the Mediterranean Sea. During the late-early Messinian, a shallowing trend occurred, culminating with the progradation of reefal carbonates. Our findings indicate that the North Rifian Corridor opened at ~ 7.2 Ma ensuring Atlantic-Mediterranean connections. The Corridor was progressively restricted during the late-early Messinian with complete closure by ~ 6.1 Ma. The results of this study thus question existing hypotheses for the timing and nature of Atlantic-Mediterranean connections during the late Messinian. [ABSTRACT FROM AUTHOR]

We present a high-resolution analysis of planktonic foraminifers, calcareous nannofossils, ostracods, dinoflagellate cysts and pollen grains in four sequences from DSDP–ODP holes in the southwestern Mediterranean Alboran and Balearic basins (976B, 977A, 978A and 134B) encompassing the previously defined Messinian–Zanclean boundary. The study focuses on (1) the marine reflooding, which closed the Messinian Salinity Crisis prior to the Zanclean GSSP; (2) the nature of the Lago Mare in the deep basins (indicated by Paratethyan dinoflagellate cysts), which appears to comprise several Paratethyan influxes without climatic control; and (3) the depositional context of the youngest Messinian evaporites which accumulated in a marine environment relatively close to the palaeoshoreline. Isolation of the Aegean Basin during the paroxysmic second step of the crisis is considered to have stored Paratethyan waters, which may then have poured into the Mediterranean central basins after deposition of the evaporitic sequence. [ABSTRACT FROM AUTHOR]

The Sorbas Basin is the land reference of the Messinian Salinity Crisis (MSC) that affected the Mediterranean Sea in the latest Miocene. Its stratigraphy has been re-visited using calcareous nannofossils and planktonic foraminifers, which provide a reliable biostratigraphic frame and lead to particularly specify the relationships between the Sorbas and Zorreras members with Yesares evaporites. The evaporites overlie a shallowing upward sequence ending with the deposition of the Reef Unit and Terminal Carbonate Complex (TCC) on the periphery of the basin. The reefal carbonates of the TCC are overlain by clastic deposits that are foreset beds of post-MSC Gilbert-type fan deltas developed on the northern edge of the basin. These sedimentary structures are separated from reefal carbonates and the Reef Unit by the Messinian Erosional Surface (MES). The various facies of the Sorbas Member have been correlated with the bottomset beds of the Gilbert-type fan deltas despite some differences in palaeobathymetry. In the southeastern periphery of the basin, the MES separates the Sorbas Member from the Yesares gypsums. In the central part of the basin, a hiatus characterizes the contact between these members. The Zorreras Member postdates the MSC and entirely belongs to Zanclean. Its white “Lago Mare” layers are lagoonal deposits, the fauna of which is confirmed to result from Mediterranean–Paratethys high sea-level exchange after the post-MSC marine reflooding of the Mediterranean Basin. This study allows to re-assert the two-step scenario of the MSC (Clauzon et al., 1996) with the following events: - at 5.971–5.600 Ma, minor sea-level fall resulting in the desiccation of this peripheral basin with secondary fluctuations; - at 5.600–5.460 Ma, significant subaerial erosion (or lack of sedimentation) caused by the almost complete desiccation of the Mediterranean Sea; - instantaneous marine reflooding, accepted at 5.460 Ma, followed by continuing sea-level rise. [ABSTRACT FROM AUTHOR]

Since the discovery of calcareous nannofossils, dinoflagellate cysts and planktonic foraminifers in deposits from the Dacic Basin, intensive research has been performed in order to evidence which gateway this microplankton used to connect Paratethys and the Mediterranean prior and after the Messinian Salinity Crisis (MSC). Such a gateway is also to be regarded at the origin of successive influxes of Paratethyan organisms (molluscs, ostracods, dinoflagellates) into the Mediterranean Basin (“Lago Mare” events). Observing that the İstanbul area, usually proposed for this purpose, was inefficient, we examine the succession of marine well-dated pre-MSC and post-MSC deltaic deposits through the Balkans, from northern Greece to southern Romania, that constitutes a reliable candidate for such a marine corridor, the origin of which was caused by the regional tectonic extension. The reconstructed palaeogeography for high sea level episodes that encompassed the MSC clarifies the context of the so-called North Aegean Lake. This marine gateway probably evolved as a powerful river during the peak of the MSC, contributing to the deposition of clastics in the hydrocarbon Prinos Field. A tectonically controlled subsidence to the north and south of the Skopje region caused the closure of such a gateway. [ABSTRACT FROM AUTHOR]