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This study attempts to integrate multiple methods to investigate the presence of malaria in human skeletal samples from an archaeological context. 33 well preserved human remains originating from a 17th-century archaeological site in southeastern Romania. The human bone samples were analyzed using rapid diagnostic tests for malaria antigens and PCR amplification of Plasmodium falciparum apical membrane antigen 1. A preliminary test was performed to identify and briefly characterize the presence of hemozoin using a combination of TEM imaging and diffraction. The rapid diagnostic tests indicated that more than half of the examined samples were positive for Plasmodium antigens, but no traces of the parasites' genetic material were detected despite repeated attempts. The TEM images indicated that hemozoin might be a promising diagnostic marker of malaria in ancient bones. The indisputable identification of malaria in the analyzed archaeological population was not possible as none of the applied methodological strategies turned out to be straightforward. This study reinforces the intricacy and limitations of unequivocally identifying malaria in past populations and sets the stage for future studies on such life-threatening infectious disease in a geographical space, which is currently underrepresented in the bioarchaeological literature. The low sample size and the lack of consistency across all assays hindered understanding the role of malaria in the studied population. Further thorough multidisciplinary approaches on malaria detection in ancient settlements would be appropriate to inform our knowledge of its origins, frequency, and pathogen changes over centuries. [ABSTRACT FROM AUTHOR]

The occurrence of marine litter in the Black Sea region is poorly known and even less data have been reported on the abundance of floating debris. Here we present results from a ship-based visual survey carried out in the North-Western part of the Black Sea, providing the first preliminary data on the characteristics of floating debris in Romanian waters. High litter densities peaking to 135.9 items/km 2 were found in the study area (mean 30.9 ± 7.4 items/km 2 ). Probably due to the proximity of the Danube delta, natural debris were on average, much more abundant than anthropogenic litter in most surveyed locations (mean 141.4 ± 47.1 items/km 2 , max 1131.3 items/km 2 ). Most of the 225 objects we sighted consisted of pieces of wood and other riparian debris (75.5%), however plastic items remained undoubtedly the most abundant type of litter, representing 89.1% of all sighted man-made items. The Black Sea is not exempt from the global invasion of floating debris, however data are still lacking and a basin-wide survey is urgently needed to identify accumulation areas and develop regionally effective solutions to the problem of marine litter. [ABSTRACT FROM AUTHOR]

The studied Cernatu Valley section is situated in the central part of the Eastern Carpathians (Romania) and spans the interval covered pro parte by the NC10a (=CC9b) calcareous nannofossil Subzone, as well as the Plectorecurvoides alternans and Haplophragmoides falcatosuturalis agglutinated foraminiferal zones. The presence, within the lower part of the section, of the ammonite Stoliczkaia notha indicates a late Albian age, but the section possibly extends to within the Albian-Cenomanian boundary interval, based on the agglutinated foraminiferal assemblages. The deposits are grey to blackish and green shales that are followed by red shales interbedded with couplets of grey to blackish and green shales. The benthic foraminifers suggest a deep-marine depositional setting, probably lower bathyal or even abyssal, at around 2500 m depth. The deposition was probably near but above the Calcium Compensation Depth (CCD), as very scarce nannofloras and macrofaunas are present. The &#94813C values vary throughout the section between -25.30‰ and -24.01‰. Within the upper Albian, a positive organic &#94813C excursion with increases of 1.3‰, up to -24.01‰, is recorded. This positive excursion has been tentatively interpreted as a regional expression of the Oceanic Anoxic Event OAE1d in the Moldavian Trough of the Eastern Carpathian basin. The upper part of the section, belonging to the Haplophragmoides falcatosuturalis agglutinated foraminiferal Zone, contains a weak positive &#94813C excursion marked by an increase in values of about 0.5‰, which is assumed to represent late phases of the Albian-Cenomanian boundary Event. Towards the top of the section, consisting mainly of red shales, calcareous foraminifera also occur, together with more consistent nannofossil assemblages. This biotic change possibly mirrored an alteration of the palaeoenvironment, which shifted from an anoxic/dysoxic setting towards an oxic one. This change is possibly linked to climatic fluctuation, i.e., the onset of a warm and humid climate mode. The intense tectonic activity that took place within the Eastern Carpathians during mid-Cretaceous times could also have been responsible for the environmental changes by modifying the circulation pattern in the Moldavian trough from a restricted circulation to a more open one. [ABSTRACT FROM AUTHOR]

The Organyà Basin, south–central Spanish Pyrenees, developed as a marginal depocenter during a rapid extensional phase of anticlockwise rotation of the Iberian plate. As a result of increased subsidence, an important change in sedimentation occurred from the late Barremian to the Aptian leading to unusually high sediment accumulation rates. Approximately 1000 m of hemipelagic marls and limestones accumulated during this time interval. Here we studied the basal 85 m of the hemipelagic facies of the El Pui section, Organyà Basin, that are characterized by alternating 15 cm – ∼3 m thick beds of limestone and marls. Geochemical analyses indicate high total inorganic carbon (TIC) values (average 70%) suggesting enhanced CaCO3 production and deposition. SEM analyses of the samples indicate high abundance of calcareous nannofossils, which together with the absence of shallow water taxa characteristic of the Urgonian Carbonate platform of Organyà, and the lack of sedimentary facies attributable to carbonate platform components point to nannofossils as the main source for the elevated TIC. Organic-rich levels (total organic carbon (TOC) up to 1.74%) concurrent with positive excursions up to 2‰ in δ13Corg, imply enhanced preservation of organic matter (OM) in the basin. In addition, pronounced peaks of δ13Corg higher than the global average suggest superimposed local factors related to intensified 12C removal due to primary productivity. Biomarker analyses and the δ13Corg profile suggest an autochthonous origin of the OM from phytoplankton and possible additional contributions from microbial communities. X-ray diffraction (XRD) results attest for sustained terrestrial fluxes as the source of nutrients to the basin because of a 30% average non-carbonate bulk mineral content in the sediment. The non-carbonate fraction is dominated by quartz (average, 14%) whereas the clay mineral assemblages are characterized by high illite content (>73 relative%) with minor concentrations of kaolinite (<5%), illite /smectite mixed layers (<17%) and chlorite (<15%), consistent with a provenance from the Paleozoic metamorphic terranes adjacent to the Organyà Basin. The integrated results suggest a high sediment accumulation rate (5 cm/ky–7.5 cm/ky) and enhanced carbon burial during the latest Barremian–earliest Aptian in the hemipelagic setting of the El Pui section. [ABSTRACT FROM AUTHOR]

Abstract: Lower Cretaceous deposits of the Tarcău Nappe, central part of the Eastern Carpathians, were studied, aiming to point out their lithofacies and to reconstruct the changes in depositional palaeoenvironment of those times. The investigated deposits extend within the NC5-NC10 calcareous nannoplankton biozones, covering the Late Barremian–Late Albian. Based on sedimentological, petrographical and geochemical features, ten lithofacies were identified, grouped in three categories, such as shaly, siliciclastic and carbonate. The shaly lithofacies consist of black and grey shales, as well as carbonate shales yielding an average of organic matter content around 3%. The organic matter and pigments of iron, such as hydrotroillite are responsible for the occurrence of the black colour. Preservation of the organic matter is due to anoxic environments induced by reduced current flow and intensified water density stratification. The siliciclastic lithofacies are mainly composed of quartz arenites, quartzwackes, and subordinately sublitharenites and lithic graywackes. The carbonate lithofacies include predominantly marls and siderites, originating by diagenetical processes of the shaly lithofacies, and subordinately calcarenites with terrigenous material and sponge spicules. The petrography and geochemistry indicate that the main sources of the sandy detrital material are the basement and sedimentary cover of the Central (Scythian) and East European platforms. The black and grey shale deposition, in the Barremian–Late Aptian interval, reflects suspension settling of the hemipelagic and pelagic material. Thin sandy beds, with parallel lamination and current ripples, suggest low-density turbidity currents, while the Albian thick sandy beds with massive or normal grading and parallel lamination are interpreted as high-density turbidity currents or even sandy debris flows. The shaly depositional intervals are linked to the basinal plain, while the sandy dominated sequences are associated with turbiditic lobes. [Copyright &y& Elsevier]

Abstract: Detailed lithological and micropaleontological studies were performed on several cores from the Romanian Black Sea shelf, located in front of the Danube Delta, in front of the Razelm–Sinoe lagoonal complex, close to the Eforie beach, as well as on the Romanian inner shelf. All the studied cores are situated at a water depth varying between 12m and 67m. The purpose of the investigations was to reveal Upper Holocene lithological changes and the associated calcareous nannoplankton fluctuations in a very shallow marine setting such as the Romanian Black Sea inner shelf. The youngest Holocene unit or “Shallow Unit” is composed of alternating sequences of mud, silt, clay and coquina layers, containing marine mollusc faunas. The upper part of the Shallow Unit contains blooms of the nannoplankton species Emiliania huxleyi, while its lower part yields, besides common E. huxleyi, rare specimens of Braarudosphaera bigelowii. The Shallow Unit overlies a “shell hash layer”, mainly made by coquinas, containing mixing marine and brackish mollusc faunas. Towards the upper part of this level, monospecific assemblages with B. bigelowii were observed in a layer rich in carbonate acicular crystals. The Shallow Unit partly corresponds to the Unit 1 (finely laminated coccolith ooze) and Unit 2 (sapropelic sediments) of slope and basinal settings of the Black Sea. The layer rich in carbonate acicular crystals could be a shallower equivalent of the oldest layer of aragonite bands placed at the lower part of the Unit 2 in deep parts of the Black Sea. In the analyzed cores, the oldest lithological unit (Unit 3, the muddy clay sediments deposited in a brackish to freshwater environment) is characterized by the deposition of green-yellowish clay devoid of any Holocene calcareous nannoplankton species and containing brackish mollusc faunas. Based on nannofloral fluctuations, an increasing salinity from the base towards the upper part of the Shallow Unit may be supposed, together with the progressive establishment of a stable marine setting, similar to today. [Copyright &y& Elsevier]

Abstract: The middle Cenomanian–lower Turonian deposits of Ohaba-Ponor section (Southern Carpathians) were studied from biostratigraphic and isotopic points of view. Both the qualitative and semiquantitative nannofloral analyses, as well as the stable isotope (δ13C and δ18O) data support significant palaeoenvironmental changes in the investigated interval. Two δ13C positive excursions were recognized: (1) an excursion up to 1.8‰ (PDB) within the middle/late Cenomanian boundary; (2) an excursion up to 2.2‰ (PDB) in the Cenomanian/Turonian boundary interval. The oldest δ13C positive excursion recorded (placed within the Acanthoceras jukes-brownei/Eucalycoceras pentagonum Ammonite Zone boundary interval, and in the NC11 Calcareous Nannofossil Zone respectively) could be assigned to the middle Cenomanian Event II (MCEII). During the above-mentioned event, significant increase in abundance of Watznaueria barnesae, followed by successive blooms of Biscutum constans and Eprolithus floralis, were observed. The youngest δ13C positive excursion was identified in the Cenomanian/Turonian boundary interval (in the NC12 and lower part of the NC13 Calcareous Nannofossil Zones). Even the amplitude of this δ13C positive excursion is lower in the Ohaba-Ponor section, as generally reported, this may represent the regional record of the OAE2. The successive peaks of the nannofossils Biscutum constans, Zeugrhabdotus erectus and Eprolithus floralis indicate episodes of cooler surface water and high fertility, which preceded and lasted the Cenomanian/Turonian boundary event. Additionally, fluctuations of δ18O values between −2 and −6‰ suggest also cooler conditions within the Cenomanian/Turonian boundary interval. [Copyright &y& Elsevier]

Abstract: Fluctuation in calpionellid, foraminiferal, and nannofossil diversity and abundance are documented in two successions located in the eastern part of the Upper Jurassic–Lower Cretaceous carbonate platform of the Southern Carpathian area, Romania. The lower part of the studied sections consists of upper Tithonian–upper Berriasian bioclastic limestones. This age is supported by the presence of the calpionellid assemblages assigned to the Crassicollaria, Calpionella, and Calpionellopsis Zones. Based on biostratigraphical data, a gap was identified within the uppermost Berriasian–base of the upper Valanginian (the interval encompasses the Boissieri, Pertransiensis, Campylotoxum, and lower part of the Verrucosum ammonite Zones). Hence, the upper Tithonian–upper Berriasian bioclastic limestones are overlain by upper Valanginian–lower Hauterivian pelagic limestones (the interval covered by the NK3B and NC4A nannofossil Subzones). A detailed qualitative and semiquantitative analysis of the nannoflora was carried out over this interval. To estimate the surface water fertility conditions, the nannoplankton-based nutrient index (NI) was calculated. The fluctuation pattern of NI allow us to recognize four phases in the investigated interval, as follows: (1) phase I (covering the lower part of the NK3B nannofossil Subzone and the upper part of the Verrucosum ammonite Zone, respectively) is characterized by low values of the NI (below 20%), by the dominance of the genus Nannoconus in the nannofloral assemblages (between 60–70%), and moderate abundance of Watznaueria barnesae (up to 23%), while the high-fertility nannofossils constitute a minor component of the assemblages; (2) phase II (placed in the NK3B nannofossil Subzone, extending from the top of Verrucosum ammonite Zone, up to the lower part of the Furcillata ammonite Zone) is characterized by increase of NI above 30%, a decrease of nannoconids (up to 50% at the top), while Watznaueria barnesae increases in abundance up to 27%. The fertility proxies (Diazomatolithus lehmanii, Zeugrhabdotus erectus, Discorhabdus rotatorius, and Biscutum constans) represent again a minor component of the recorded nannofloras (less than 7% in both sections), but they have an ascending trend; (3) phase III (which encompasses the boundary interval of the NK3B and NC4A nannofossil Subzones, corresponding to the upper part of the Furcillata ammonite Zone) contains higher NI values (over 35%, and up 52% towards the base of this phase), an abrupt nannoconid decrease (down to 20%), higher abundance of Watznaueria barnesae (over 30%), while the fertility nannofossils became an important nannofloral component, jointly amounting to almost 20%; (4) phase IV (identified within the NC4A Nannofossil Zone and corresponding to the boundary interval of the Furcillata and Radiatus ammonite Zones) is characterized by a decrease of NI to 25%, a recovery of the nannoconids up to 40%, a decline in abundance of Watznaueria barnesae to 25%, together with a pronounced drop of fertility taxa, which make together no more than 8%. We assume that maximum of eutrophication in the studied interval from the Southern Carpathians was in the Furcillata ammonite Zone. Notably, within the phases 2 and 3, the morphological changes identified in the benthic foraminiferal assemblages (the predominance of flattened morphologies, together with the presence of conical and trochospiral inflated forms), as well as the occurrence of the Zoophycos trace fossils and pyrite framboids, indicate dysaerobic conditions. In the Southern Carpathians, the late Valanginian–early Hauterivian biogeographical changes are coeval with the initiation of the carbonate platform drowning. [Copyright &y& Elsevier]

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]

The Zambezi Delta draining the Southern African Plateau and the southern part of the East African Rift is one of a the largest delta of Africa with a long-lasting history starting during Early Cretaceous with more than 12 km of sediments deposited. The Zambezi Delta is therefore a unique archive of the past topographic evolution of southern and eastern Africa and their related deformations, but also of the climate changes, global and regional (consequences of local topographic growths). Understanding this archive supposes to get a high-resolution dating of the sediments. Our two objectives are here (1) to construct an age model of the Zambezi Cenozoic delta using a combination of biostratigraphy, orbital stratigraphy and sequence stratigraphy and (2) to determine the palaeoprecipitation variations of the Zambezi catchment from the Oligocene to present day in a known tectonic framework. The Neogene sequences were dated at high-resolution assuming that the third order sequences are of eustatic origin and record long-term eccentricity cycles. The sequences were correlated in ages on the calculated Earth orbital solutions of Laskar for the time intervals provided by the biostratigraphy (nannofossils, planktonic foraminifers). The palaeoprecipitation record was based on the definition of a humidity index based on pollen analysis and associated botanical associations. The late Oligocene was a quite wet period getting dryer in the uppermost Chattian. The base Tortonian (11 Ma) was a humid period. The Messinian was a dry period with a slight increase of the humidity during the Zanclean and a sharp increase around the Zanclean-Piacenzian boundary. The Zambezi Delta has recorded the uplifts of the Southern African Plateau (around 85 Ma and around 25 Ma) and those of the southward migration of the East African Rift (since 5.5 Ma). Image 1 • Dating sediments with a resolution of 0.1 Myr combining seismic stratigraphy, biostratigraphy an orbital stratigraphy. • Quantifying palaeoprecipitations using a humidity index on botanical associations from pollens. • Characterization of uplifts at 85 and 25 Ma (South African Plateau) and 5.5 Ma (migration of the East African Rift). [ABSTRACT FROM AUTHOR]

Widespread evaporites were deposited in large parts of the Central Paratethys during the so-called Badenian Salinity Crisis (BSC). The adverse environmental conditions that accompanied the BSC triggered a demise in the basin's marine fauna, inducing the so-called middle-Badenian-extinction-event. While tectonic activity preconditioned the Central Paratethys for isolation, it has recently been shown that the BSC was eventually triggered by the base-level drop accompanying the Mi3b global cooling event, which terminated the Middle Miocene Climatic Optimum. Here, we provide new constraints on the termination of the BSC by 40 Ar/ 39 Ar dating of a volcanic ash layer, located in a marl succession several meters above the Badenian evaporites of the Slănic Syncline in the Romanian East Carpathians. The results reveal that the BSC ended before 13.32 ± 0.07 Ma. Comparison with previously obtained geochronological results in Poland constrains the duration of the BSC to 500 kyr, assuming evaporite deposition in the Central Paratethys occurred as one event. The obtained 40 Ar/ 39 Ar results are complemented with paleomagnetic and micropaleontological analyses. These reveal that the investigated post-BSC marl interval in the Slănic Syncline was deposited in a period of reversed polarity corresponding to C5AAr. This is in agreement with calcareous nannoplankton from the same interval that belong to the NN6 zone. Ostracod and foraminifera marker species are indicative of the middle part of the regional Badenian stage, traditionally known as the Wielician. The foraminiferal assemblage is nevertheless very similar to Serravallian assemblages from the Mediterranean, which suggests that, in addition to a connection between the Central Paratethys and the Eastern Paratethys, there was a marine connection with the Mediterranean following the BSC. A comparison with post-BSC successions in Ukraine and Poland illustrates that the BSC was terminated by a transgression that re-installed normal marine conditions in the Carpathian foredeep. This basin-wide transgression resulted from reconnection of the Carpathian Foreland Basin with the Mediterranean and Eastern Paratethys, which improved the exchange of water and fauna. Global eustacy cannot explain re-connection of these basins, because global sea level on average remained just as low after the BSC as it had been during the crisis. The improved interconnectivity between the basins must therefore have been primarily caused by tectonic modification of the interconnecting gateways. Geodynamics thus played a crucial role in the re-establishment of a flourishing marine environment. [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]

Phylogenetic studies of present-day terrestrial organisms suggest that faunal dispersals between South America and the Greater Antilles may have occurred during the Cenozoic through the Lesser Antilles. However, because of the lack of geological data to unravel the areas that may have emerged along the Lesser Antilles trench, the migration paths used by their ancestors remain unknown. Here, we present novel paleogeographic maps of the central Lesser Antilles (extending from Guadeloupe to Martinique islands) which are built on the basis of onshore and offshore stratigraphic correlations (50 seismic lines, biostratigraphy of 9 dredged and 29 field samples, six sedimentary logs). We find that repetitive episodes of uplift and drowning have occurred in the central part of the Lesser Antilles during the Neogene. Offshore, the Marie-Galante Basin comprises three sedimentary megasequences that deposited between: (i) the Oligocene and Early Miocene, including the extinct arc, (ii) the Middle and Late Miocene and (iii) the latest Miocene and Holocene. These sediments infill a NNW-SEE trending forearc rift that opened during the Early Miocene. The megasequences are separated by subaerial regional unconformities that affect the rift shoulders. Onshore, we show that the lower part of the carbonate platform in Guadeloupe and La Désirade has deposited during the late Messinian. In Martinique, we refine the age of the carbonate deposits belonging to the extinct arc to the Chattian-Burdigalian, and evidence a major subaerial unconformity corresponding to the Middle Miocene. We propose that between Anguilla and Martinique, from north to south, large archipelagos, which are now drowned, have existed during the early Middle Miocene and the latest Miocene. We suggest that during the Miocene, the Lesser Antilles may have been used as a pathway for land-faunal dispersals from South America. • The Marie Galante Basin comprises three Eocene to present-day seismic megasequences. • The Marie Galante Basin is an intra-arc rift with two Miocene uplifts. • Martinique displays an early Middle Miocene uplift. • ArChipelagos existed by the early Middle and latest Miocene in the Lesser Antilles. • The Lesser Antilles can be a pathway for Cainozoic terrestrial fauna migrations. [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]

The two sides of the Strandja Sill show a highly discontinuous stratigraphic succession since the Late Oligocene. This area, together with the Sea of Marmara Basin, is usually proposed as the gateway for the Paratethyan freshwaters and organisms that constituted the Lago Mare facies in the Mediterranean Sea during the Messinian Salinity Crisis (MSC). Our investigations involving new field observations and datings, together with previous studies, suggest that the sill has possibly experienced such a connection at around 8 Ma, i.e. significantly before the crisis. The proposal of a sea-level drop of the Black Sea before 7 Ma is not supported by our data on dinoflagellate cysts. Consistency of calcareous nannofossil succession at DSDP Site 380 is reinforced, allowing to reassert that subaerial erosion impacted both the southwestern Black Sea and the central Marmara – Dardanelles area during the peak of the MSC. At that time, this region was crossed by two oppositely directed fluvial networks, further supporting the absence of a marine gateway through the Strandja Sill. It is concluded that none of the Lago Mare events recorded in the Mediterranean during the MSC were the consequence of the passage of Paratethyan waters and organisms through this area. In the Black Sea, the well-dated Messinian fluvial erosion can be followed offshore. The overlying prograding deltaic deposits attest to a fast marine reflooding after the crisis. This constitutes a comprehensive erosion – sedimentation model in an area intensively explored for hydrocarbons. [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]

The Karukéra spur is an easternmost submerged rise of the Lesser Antilles fore-arc in the Guadeloupe archipelago, culminating about 4000 m above the fore-arc basin 150 km west of the deformation front. The analysis of 3500 km 2D high-resolution multichannel seismic reflection and multibeam bathymetric data, and the study of 14 core samples, allow for the first time to reconstruct its sedimentary anatomy and tectonic evolution. Seven seismic units (U S1 to U S7 ) are evidenced, organised into four major depositional sequences separated by erosional surfaces. Units U S1 to U S4 thicken to the south-southeast on the spur. The sedimentary deposits rest upon a deeply eroded metamorphic basement of the Caribbean Plate as in La Désirade Island. Sequence 1 (units U S1 and U S2 ) remains unknown in its lower part because it does not outcrop. Its upper part comprises early Miocene shallow water carbonates. Sequence S2 (Unit U S3 ) only comprises an upper Miocene transgressive systems tract deposited into basinal environment. It is bounded by major erosional surfaces SB2 and SB3. Sequence 3 (U S4 to U S6 ) is Zanclean to Pleistocene. It is dominantly composed of shallow water, reefal deposits. Sequence 4 corresponds to recent deposits. The Karukéra spur experienced three main extensional episodes with alternations between uplift and subsidence periods. Uplifts are responsible for emersions and erosions. Subsidence severely drowned shallow water deposits. The first extensional episode led to the formation of horsts and grabens in the basement, prior to early Miocene deposits. The second extensional episode occurred during upper Miocene, in accordance with data in surrounding islands. The third tectonic episode developed since Calabrian. Noticeable is the constant reactivation of N130°–N150°, N150°–N180° and N40° trending faults since early Miocene and the neoformation of E–W trending faults since Calabrian. Our results suggest that at the latitude of Guadeloupean archipelago the Lesser Antilles subduction zone is an erosional margin because of the successive sweepings of the Santa Lucia then Tiburon Ridges. [ABSTRACT FROM AUTHOR]

The essential characteristics of the vegetation dynamics of tropical Africa remain only partially known. This study assesses the succession of vegetation-types over Central Africa during the last two glacial/interglacial cycles. Analysis of core KZai 02, which contains pollen from the Zaire River watershed (latitudes 9°N–13°S), allows the investigation of long-term patterns of plant ecosystem development and their climatic causes. Core KZai 02 (18.20 m long) was recovered from 6°24.20′S/9°54.10′E in the uppermost axial edifice of the Zaire deep sea fan. The chronology of this sedimentary archive was established using nannofossils and correlations of pollen and total organic carbon signals with the nearby core GeoB1008. The pollen record indicates that: (i) glacials (MIS 6, 4, 2) are marked by the development of afromontane ( Podocarpus ) forest at high altitudes when central basin lowlands were occupied by Cyperaceae marshes and savannah; (ii) during interglacials (MIS 1, 5) lowland forests were developed, marked by the successive expansion of pioneer, warm-temperate, rain forests, and mangrove indicating sea-level rise; (iii) glacial-interglacial transitions (MIS 6/5, 2/1) display similar vegetation dynamics. The strong evidence of afromontane forest and the opening of the vegetation during glacials suggest a reduced latitudinal distribution of rainfall by the strengthening of the trade wind system. West African monsoon systems were enhanced during interglacials, allowing the progressive development of lowland forests. The development of rain and pioneer forests during glacial Heinrich stadials suggests an enhancement of water availability in tropical Africa associated with these high-latitude events. However, no augmentation of wind activity described by previous studies is evidenced by our pollen record. Similar vegetation successions during glacial/interglacial transitions suggest the diachronous and stepped intervention of CO 2 (emphasizing the influence of temperature on plant ecosystems) and water availability. [ABSTRACT FROM AUTHOR]

Located on the margin of the west Alboran basin, the Gibraltar Arc (Betic-Rif mountain belt) displays post-Pliocene vertical movements evidenced by uplifted marine sedimentary basins and marine terraces. Quantification of vertical movements is an important clue to understand the origin of present-day relief generation in the Betic-Rif mountain chain together with the causes of the Messinian Salinity Crisis. In this paper, we present the results of a pluridisciplinary study combining an analysis of low temperature thermochronology and Pliocene basins evolution to constrain the exhumation history and surface uplift of internals units of the Rif belt (Northern Morocco). The mean (U-Th)/He apatite ages obtained from 11 samples are comprised between 14.1 and 17.8Ma and display a wide dispersion, which could be explained by a great variability of apatite chemistries in the analyzed samples. No correlations between altitude and age have been found along altitudinal profile suggesting a rapid exhumation during this period. Thermal modeling using our (U-Th)/He apatite ages and geochronological data previously obtained in the same area (40Ar/39Ar and K/Ar data on biotite, zircon and apatite fission track) allow us to propose a cooling history. The rocks suffered a rapid cooling at 60–100°C/Ma between 22.5 and 19Ma, then cooled to temperatures around 40°C between 19 and 18Ma. They were re-heated at around 110°C between 18 and 15Ma then rapidly cooled and exhumed to reach the surface temperature at around 13Ma. The re-heating could be related to a renewal in thrusting and burying of the inner zones. Between 15 and 13Ma the cooling resumed at a rate of 50°C/Ma indicating an exhumation rate of 0.8mm/y considering an average 40°C/km geothermal gradient. This exhumation may be linked to the extension in the Alboran Sea. Otherwise biostratigraphic and sedimentological analysis of Pliocene basins of the internal Rif provided informations on the more recent events and vertical movements. Pliocene deposits of the Rifian coast represent the passive infilling of palaeo-rias between 5.33 and 3.8Ma. The whole coastal area was uplifted at slow average rates (0.01–0.03mm/y) in relation with a northeastward tilting of 0.2–0.3° since the Lower-Pliocene. A late Pliocene to present extensional tectonics associated to uplift has been identified all along the coastal ranges of the Internal Zone of the Rif chain. This extension was coeval with the major late Pliocene to Pleistocene extensional episode of the Alboran Sea and appears to be still active nowadays. No significant late Messinian uplift was evidenced, thus calling into question the geodynamic models relating the closure of the marine gateways and the MSC to slab roll back. [ABSTRACT FROM AUTHOR]