Jean-Pierre Suc
email: jeanpierre.suc@gmail.com

Hervé Gillet

M Namik Cagatay

Speranta-Maria Popescu

Gilles Lericolais

Mihaela Rolando Armijo

Carmen Melinte-Dobrinescu

Şevket Şen

Georges Clauzon

Mehmet Sakinç

M Namik Çağatay

Carmen Mihaela

Melinte-Dobrinescu

Mehmet Sakınç

Cengiz Zabcı

Gülsen Ucarkus

Bertrand Meyer

Ziyadin Çakir

Çağil Karakaş

Gwenaël Jouannic

Rodica Macaleţ

The region of the Strandja Sill (North Turkey) and the Messinian events

Keywords: Mediterranean-Paratethys connection, Onshore-offshore stratigraphy, Messinian Salinity Crisis, Erosion, Fluvial network

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Introduction

The region of the Strandja Sill is a relatively low land area, located to the west of the Bosphorus Strait, which today constitutes the water divide between the Marmara Sea and the Black Sea (Fig. 1). Along the profile a -b (Figs. 1,2), its altitude varies between 100 and 200 m, except for some depressions often occupied by lakes and lagoons, with the highest points on the Marmara side (Fig. 2). The region is crossed by the presently inactive N-S trending West Black Sea Fault (Fig. 1B; Okay et al., 1994), and bordered to the West by the Thrace-Eskişehir Fault Zone inactive since the Pliocene [START_REF] Perinçek | Possible Strand of the North Anatolian Fault in the Thrace Basin, Turley-An Interpretation[END_REF], and to the South by the North Anatolian Fault in the Sea of Marmara [START_REF] Armijo | Westward propagation of the North Anatolian fault into the northern Aegean: Timing and kinematics[END_REF][START_REF] Armijo | Asymmetric slip partitioning in the Sea of Marmara pull-apart: a clue to propagation processes of the North Anatolian Fault[END_REF]Yaltırak et al., 2000;[START_REF] Imren | The North Anatolian Fault within the Sea of Marmara: a new interpretation based on multichannel seismic and multi-beam bathymetry data[END_REF][START_REF] Le Pichon | The active Main Marmara fault[END_REF][START_REF] Şengör | The North Anatolian Fault: a new look[END_REF], 2014). Because of its morphology and topography, the region has long been usually considered as a gateway that is supposed to have been periodically connecting the Black and Aegean seas, i.e. the Eastern Paratethys and the Mediterranean (Fig. 1A; [START_REF] Rögl | Vom Zerfall der Tethys zu Mediterran und Paratethys. Die neogene Paläogeographie und Palinspastik des zirkum-mediterranen Raumes[END_REF][START_REF] Çağatay | Paratethyan -Mediterraenan connectivity in the Sea of Marmara region (NW Turkey) during the Messinian[END_REF][START_REF] Popov | late Miocene to Pliocene palaeogeography of the Paratethys and its relation to the Mediterranean[END_REF] before its uplift that palaeogeographic reconstructions attributed to a compressional tectonics [START_REF] Sakınç | Palaeogeographical evolution of the Thrace Neogene Basin and the Tethys-Paratethys relations at northwestern Turkey (Thrace). Palaeogeogr., Palaeoclimatol[END_REF][START_REF] Sakınç | Messinian crisis: What happened around the northeastern Aegean?[END_REF]. Such a connection is generally considered to have allowed the invasion of Paratethyan organisms into the Mediterranean at the time of the Messinian Salinity Crisis (MSC), recorded within the Lago Mare facies [START_REF] Orszag-Sperber | Changing perspectives in the concept of "Lago-Mare" in Mediterranean Late Miocene evolution[END_REF][START_REF] Krijgsman | Rise and fall of the Paratethys Sea during the Messinian Salinity Crisis[END_REF].

The interest for this region increased since the evidence of a well-marked erosional surface in the southwestern Black Sea from DSDP Site 381 to Site 380 (Hsü andGiovanolli, 1979-1980) has been referred as the Messinian Erosional Surface (MES) by [START_REF] Gillet | Messinian event in the black sea: Evidence of a Messinian erosional surface[END_REF]. This ascription was supported by the palynological study of [START_REF] Popescu | Late Miocene and early Pliocene environments in the southwestern Black Sea region from high-resolution palynology of DSDP Site 380A (leg 42B)[END_REF] and recently robustly confirmed by a detailed and complete climatostratigraphic record and, especially, a succession of consistent calcareous nannofossil assemblages [START_REF] Popescu | Pliocene and Lower Pleistocene vegetation and climate changes at the European scale: Long pollen records and climatostratigraphy[END_REF].

Following some successes, hydrocarbon exploration is revitalized in the Black Sea with the possibility of an unconformity (MES) type trap and clastic reservoirs at base of the Pliocene [START_REF] Tari | Play types and hydrocarbon potential of the deepwater Black Sea, NE Bulgaria[END_REF][START_REF] Tari | The signature of the Mediterranean Messinian Salinity Crisis in the Black Sea and Caspian Basins: A Comparison[END_REF][START_REF] Georgiev | Geology and Hydrocarbon Systems in the Western Black Sea[END_REF][START_REF] Sacleux | Impact of the Messinian Crisis on petroleum systems[END_REF][START_REF] Nikishin | New set of seismic data for Black Sea. Black Sea & Caspian 2014 Conference[END_REF].

On the basis of the present-day available information, this work aims to specify if the Strandja Sill may have been a marine gateway at the time of the MSC by (1) providing new datings on the related sedimentary sequences onshore, (2) presenting new onshore data on the Black Sea side (Fig. 1B), and (3) providing unpublished offshore seismic profiles in the SW Black Sea (Fig. 1B).

Methods.

Field investigation was the main tool used in this work. It involved mostly calcareous nannofossil analyses, which were performed using a light polarizing microscope at x1600 magnification. Taxonomic identification followed [START_REF] Perch-Nielsen | Cenozoic calcareous nannofossils[END_REF] and [START_REF] Young | Chapter 9: Neogene[END_REF]. Some pollen grain and dinoflagellate cyst analyses have been made after a classical treatment of clayey samples: HCl and HF acid digestions followed by a separation within ZnCl 2 at density 2 and finally sieving at 10 µm.

Three high-resolution multichannel seismic profiles acquired during the Ifremer's BlaSON2 survey (August-September, 2002) by the R/V "Le Suroît" were used. Age assignments to the seismic stratigraphic units were made using correlations with the welldated units in the offshore petroleum exploration boreholes [START_REF] Gillet | Messinian event in the black sea: Evidence of a Messinian erosional surface[END_REF]. Because the in situ measured velocities were not available for these boreholes, we based their depth to time conversion on the BlaSON 2 seismic data stack velocities (see: [START_REF] Gillet | Messinian event in the black sea: Evidence of a Messinian erosional surface[END_REF].

Geological setting of the Strandja Sill and new biostratigraphic data on the youngest sediments

The Strandja Sill, as observable along the simplified section a -b from Figure 1, displays a stratigraphic succession starting with the Lower Carboniferous Trakya Formation (siliceous shales, sandstones, limestones, conglomerates) of the İstanbul Zone (Okay et al., 1994;[START_REF] Okay | Tethyan sutures of northern Turkey[END_REF] unconformably overlain by the Middle-Upper Eocene sediments of the Thrace Basin (sandstones, marls, limestones) (Figs. 1B, 2; [START_REF] Yurtsever | İstanbul F21[END_REF][START_REF] Less | Stratigraphy and Larger Foraminifera of the Middle Eocene to Lower Oligocene Shallow-Marine Units in the Northern and Eastern Parts of the Thrace Basin, NW Turkey[END_REF]. The youngest sediments, from Oligocene to Upper Miocene, are unconformably distributed both on the Marmara Sea and Black Sea sides of this succession (Figs. 1, 2; [START_REF] Okay | Faulting, basement uplift and carbonate sedimentation: Çatalca region, West of İ stanbul[END_REF].

Age of the Oligocene and Miocene units

On the Marmara Sea side of the transect, the Danişment Formation made of cross-bedded diversified gravels and pebbles in a reddish matrix is ascribed to the Late Oligocene [START_REF] Duman | İstanbul Metropolu Batisindaki (Küçükcekmece -Silivri -Çatalca yöresi) Kentsel Gelisme Alanlarinin Yer Bilim Verileri[END_REF]. The overlying Neogene Çukurçeşme Formation mostly consists of sands and gravels which, at Küçükçekmece (Fig. 1B), provided a mammal fauna, the main elements of which are Deinotherium giganteum, Choerolophodon pentelici, Paramachairodus orientalis, Felis cf. attica, Percrocuta senyureki, Ictitherium sp., Indarctos arctoides, Lutra sp., Amphiorycteropus gaudryi, Hipparion sp., Chilotherium habereri, Ceratotherium neumayri, Microstonyx erymanthius, Dorchatherium puyhauberti, Bohlinia attica, Orasious speciosus, Gazella gaudryi, Helicotragus rotundicornis, Palaeoreas lindermayeri and Tragoportax amalthea (Malik and Nafız, 1933). Above it, the Bakırköy Formation, consisting of limestone interbedded with claystone at the base, is ascribed to the Mid-Upper Miocene on the basis of its Mactra-rich mollusc fauna that is assigned to the Paratethyan Sarmatian s.l. Stage [START_REF] Chaput | Les faunes de Mollusques des terrains à Hipparion gracile de Küçük Çekmece près Istanbul (Turquie)[END_REF][START_REF] Gillet | Neue biostratigraphische Ergebnisse aus dem brackischen Neogen an Dardanellen und Marmara-Meer (Türkei)[END_REF]. This age has been confirmed on the basis of micropalaeontological analyses by Şafak et al. (1999).

New data on the Oligocene and Miocene units

Since 2005, we have performed several field investigations on both sides of the Strandja Sill, with the aim to obtain new age data from the Oligocene and Miocene sections. The results are described below, first for the Sea of Marmara side of the sill, and then for the Black Sea side.

Sea of Marmara side

The Beykent section (Fig. 1B: 41°01'06.56" N; 28°37'45.11" E; altitude at the top of the section: 198 m), due to a recent excavation for buildings, displays the complete Late Paleogene -Neogene sedimentary successions of the Marmara side of the Strandja Sill (Fig. 2). The 24 m-thick section, from bottom to top, consists of (Figs. 3A,B): -12 m thick, cross-bedded polygenic conglomerate (Upper Oligocene Danişment Formation) (Fig. 3C) with a reddish matrix and some clayey lenses (Fig. 3D); -3 m thick grey sands (Fig. 3E) with an erosional base (Mid-Upper Miocene Çukurçeşme Formation); -9 m thick alternating dark to light tabular clays and limestones (Fig. 3E) with silty to sandy layers (Mid-Upper Miocene Bakırköy Formation) which conformably overlays the Çukurçeşme formations. The Hipparion fauna from Küçükçekmece (Fig. 1B; [START_REF] Malik | Vertébrés fossiles de Küçük Çekmece[END_REF], which dates the Çukurçeşme Formation, has been revised (see above for the faunal list). Its estimated age is latest Mammalian Neogene MN10 Zone, i.e. ranging between 9 and 8.7 Ma. The six samples taken within the Bakırköy Formation for search of calcareous nannofossils were barren.

The Bakırköy Formation can also be observed in the cliffs bordering the Sea of Marmara shoreline at Avcılar (Fig. 1B: 40°58'19.34" N;28°44'07.05" E;altitude: 17 m). It shows almost the same lithological succession as at Beykent with a greater abundance of limestone at its top (Fig. 4). Six samples have been taken for searching calcareous nannofossils (Fig. 4): samples 3, 4 and 5 were barren. Samples 1, 2 and 6 provided poor nannofloras, with low diversity (number of species) and abundance (number of recorded specimens), composed of Sphenolithus abies, Coccolithus pelagicus, Reticulofenestra pseudoumbilicus, small reticulofenestrids, and the calcareous dinoflagellate Thoracosphaera spp. Reworked nannofossils of Cretaceous, Eocene and Oligocene are frequent. The only biostratigraphic marker species of this assemblage, R. pesudoumbilicus, has a range from the late Early Miocene to late Zanclean, and Sphenolithus abies from the late Mid-Miocene to 3.7 Ma [START_REF] Martini | Current Tertiary and Quaternary calcareous nannoplankton stratigraphy and correlations[END_REF][START_REF] Raffi | A review of calcareous nannofossil astrobiochronology encompassing the past 25 million years[END_REF]. We found some molluscs from the base of the sands overlying sample 4 (Fig. 4) with Hydrobia sp., Cardium sp. and Pirenella sp. which indicate a Sarmatian s.l. age with respect to the Paratethyan Stratigraphy, in agreement with the late Sarmatian s.l. age proposed by [START_REF] Gillet | Neue biostratigraphische Ergebnisse aus dem brackischen Neogen an Dardanellen und Marmara-Meer (Türkei)[END_REF], on the basis of a richer malacofauna from the same beds. According to [START_REF] Vasiliev | Magnetostratigraphy and radio-isotope dating of upper Miocene-lower Pliocene sedimentary succession of the Black Sea Basin (Taman Peninsula, Russia)[END_REF], the top of the Upper Sarmatian s.l. (= Kersonian) is located at about 8 Ma.

Because of the absence of any unconformity between the Bakırköy and Çukurçeşme formations, and according to the age indicated by the Küçük Çekmece mammal fauna (9 -8.7 Ma) and the late Sarmatian s.l. age of the Mactra fauna, we consider an age close to 8 Ma for the top of the Bakırköy Formation, which is consistent with the occurrence of the nannofossil Reticulofenestra pseudoumbilicus.

At Kayabaşı (Fig. 1B: 41°06'13.57" N; 28°46'37.26" E; altitude: 115 m), a thin clayey layer within carbonates unconformably topping the Eocene deposits provided a poor nannoflora with Coccolithus pelagicus, Reticulofenestra minuta, R. haqii and Sphenolithus abies, covering the Mid-Miocene to the Early Pliocene interval [START_REF] Martini | Current Tertiary and Quaternary calcareous nannoplankton stratigraphy and correlations[END_REF][START_REF] Raffi | A review of calcareous nannofossil astrobiochronology encompassing the past 25 million years[END_REF].

Black Sea side

The Akpınar quarry (Fig. 1B: 41°16'46.64" N; 28°49'04.77" E; altitude at the base of the quarry: 55 m) displays an impressive 37 m-thick lignite-clay succession overlain by sandygravelly-clayey deposits (Figs. 2,5A). According to the geological map, the lower part belongs to the Danişment Formation of Late Oligocene age and the upper part to the Belgrad Formation of Middle-Late Miocene age [START_REF] Yurtsever | İstanbul F21[END_REF]. A stratigraphic gap probably separates the two parts of this succession. Teeth of a lagomorph (Albertona sp., primitive form) and a rodent (Eucricetodon sp.) were recorded from the muck of the excavation. The first one is known in Early Miocene localities in Greece and Turkey (Ünay et al., 2001). However, the described species have a more evolved dentition than that of the Akpınar quarry. Eucriceton is a common genus in Oligocene and Early Miocene of Eurasia [START_REF] Hugueney | Genera Eucricetodon and Pseudocricetodon[END_REF]. These mammals can be considered for dating the lower part of the quarry. Some samples have been analysed for calcareous nannoplankton and palynology (Fig. 5B,5C). Only sample 4 contains nannofloral assemblage with, among others, the following biostratigraphic markers: Calcidiscus macintyrei, Cyclicargolithus floridanus, Sphenolithus abies and Reticulofenestra pseudoumbilicus. C. floridanus disappeared in the late Mid-Miocene [START_REF] Martini | Current Tertiary and Quaternary calcareous nannoplankton stratigraphy and correlations[END_REF], at ca. 12 Ma [START_REF] Raffi | A review of calcareous nannofossil astrobiochronology encompassing the past 25 million years[END_REF], and C. macintyrei appeared in the Mid-Miocene [START_REF] Martini | Current Tertiary and Quaternary calcareous nannoplankton stratigraphy and correlations[END_REF], at ca. 12.4 Ma [START_REF] Raffi | A review of calcareous nannofossil astrobiochronology encompassing the past 25 million years[END_REF]). An age of ca. 12 Ma (late Middle Miocene), consistent with the occurrence of R. pseudoumbilicus and S. abies (see above; [START_REF] Martini | Current Tertiary and Quaternary calcareous nannoplankton stratigraphy and correlations[END_REF], may be considered for the uppermost clays of this succession. This lacustrine succession probably discontinuously ranges in age from the Late Oligocene to Early and Middle Miocene. This is consistent with the pollen content of samples 1, 2 and 3 (Figs. 5B, 5C) which indicates freshwater swampy to riparian conditions with predominance of Taxodium-type, Alnus, Engelhardia, Myrica, Zelkova, Carya, etc. Such a pollen assemblage is already known from Oligocene of the Thrace Basin (İslamoğlu et al., 2010). Sample 3 (Fig. 5C) is also characterized by abundant spores of Pteridophyta, which indicates some fluvial input.

The upper part of the Miocene succession can be observed at Kocayemiş (Fig. 1: 41°13'2.67" N; 28°47'22.09" E; altitude: 100 m) where blue clays with cm-thick lignites alternate with channelled reddish sands and gravels in 25 m-thick section. Four samples from these clays did not provide any calcareous nannofossil.

To the West, in the area of Karacaköy (Fig. 1B), important differences in sedimentation and geomorphology characterize the two sides of the Strandja Ranges, made of the old basement rocks (granites, schists, quartzites, etc.; [START_REF] Çağlayan | 000 ölçekli Türkiye Jeoloji Haritaları[END_REF], through the Karamandere pass. The sediments on both sides of the pass are usually ascribed to the Ergene Formation (Sakinç et al., 1999), which is Upper Miocene in age according to [START_REF] Çağlayan | 000 ölçekli Türkiye Jeoloji Haritaları[END_REF]. In the West Thrace Basin, the Upper Miocene age of the sediments is attested by the Late Vallesian mammal fauna of Yulafli [START_REF] Kaya | Late Miocene Rhinocerotids (Mammalia) from Yulafli (Çorlu-Thrace/Turkey)[END_REF][START_REF] Geraads | Late Miocene large mammals from Yulafli, Thrace region, Turkey, and their biostratigraphic implications[END_REF]. However, the sediments filling the triangular area of Karacaköy northward of the Karamandere pass are not dated, but were previously ascribed to Pliocene (Ternek, 1964), a concept which at that time also encompassed the latest Miocene. Southward of the pass, the surface sediments (locality 1 in Figure 6A) are constituted by reddish alluvial loams and gravels affected by pedogenetic alteration. They are cut by quartz veins (Fig. 6B). Such deposits correspond to an alluvial plain with lens-shaped channel intercalations, also attested by the almost flat surface morphology at an altitude between 170 and 200 m (Fig. 6A). On the northern edge of the Karamandere pass, the sediments are composed of almost horizontal yellowish to whitish cross-bedded sands and gravels (Figs. 6C -E) while the altitude of their top progressively decreases from 115 m at locality 2 to 81 m at locality 4 (Fig. 6A). Such sediments are typical of fluvial-deltaic deposition that is also supported by their triangular geometry (Fig. 6A) their content of abundant transported tree trunks (Fig. 6F). At the Karamandere pass and immediately northward (Fig. 7A), these fluvial-deltaic sediments are obviously nested within the basement of the Strandja Ranges (Fig. 7B), from which we consider that they are separated by an erosional surface (Figs. 6A and7B). [START_REF] Popescu | Late Miocene and early Pliocene environments in the southwestern Black Sea region from high-resolution palynology of DSDP Site 380A (leg 42B)[END_REF] her figure 3) documented several layers with dinoflagellate cysts below the Pebbly Breccia Unit which, at DSDP Site 380, has been considered to mark the Messinian Salinity (Hsü andGiovanoli, 1979-1980), between 883.50 and 864.50 m1 . As a support to this ascription, the earliest Zanclean is indicated by two marker species, Ceratolithus acutus and Triquetrorhabdulus rugosus [START_REF] Raffi | A review of calcareous nannofossil astrobiochronology encompassing the past 25 million years[END_REF] Magyar et al., 1999aMagyar et al., , 1999b)). These samples also document inflows of marine waters into the Black Sea before and after the Messinian Crisis, probably from the Mediterranean Sea. The sample at 840.07 m marks the beginning of a long sequence of Mediterranean water inflow, at least up to 704.34 m as documented by [START_REF] Popescu | Late Miocene and early Pliocene environments in the southwestern Black Sea region from high-resolution palynology of DSDP Site 380A (leg 42B)[END_REF].

Deep Black Sea

Messinian erosion in the Black Sea

Southwestern Black Sea

The BlaSON1 and 2 surveys (Ifremer: 1998 and2002, respectively) have tracked an erosional surface in several seismic profiles [START_REF] Gillet | La stratigraphie oligo-miocène et la surface d'érosion messinienne en mer Noire, stratigraphie sismique haute résolution[END_REF][START_REF] Gillet | Messinian event in the black sea: Evidence of a Messinian erosional surface[END_REF], which was previously detected by [START_REF] Letouzey | Black Sea: geological setting and recent deposits distribution from seismic reflection data[END_REF], particularly between DSDP Sites 381 and 380 (Fig. 1B). This erosional surface was attributed to a significant sea-level fall in the Black Sea as a consequence of the Messinian Salinity Crisis in the Mediterranean [START_REF] Gillet | Messinian event in the black sea: Evidence of a Messinian erosional surface[END_REF], marked at Site 380 by the above mentioned Pebbly Breccia composed of dolomitic clasts and stromatolitic dolomite blocks (Hsü andGiovanoli, 1979-1980). This interpretation was supported by the stratigraphic subdivision of several petroleum exploration wells [START_REF] Gillet | Messinian event in the black sea: Evidence of a Messinian erosional surface[END_REF], such as İğneada 1 and Karadeniz 1 located in our study area (Fig. 1B). At last, an age of 5.45 Ma has been assigned at Site 380 to the lowermost Aragonitic mud Unit (at 861.65 m bsf) which immediately overlies the Pebbly Breccia (Fig. 8), on the basis of a reliable succession of calcareous nannofossils and a robust climatostratigraphy from pollen data in narrow relationship with well-dated Mediterranean and European pollen records [START_REF] Popescu | Pliocene and Lower Pleistocene vegetation and climate changes at the European scale: Long pollen records and climatostratigraphy[END_REF]. Previous studies interpreted the sea-level fall in the Black Sea as a climatic consequence of the severe sea-level drop of the Mediterranean [START_REF] Popescu | Late Miocene and early Pliocene environments in the southwestern Black Sea region from high-resolution palynology of DSDP Site 380A (leg 42B)[END_REF][START_REF] Vasiliev | Impact oft he Messinian Salinity Crisis on Black Sea hydrology-Insights from hydrogen isotopes analysis on biomarkers[END_REF]. This assertion is supported by a palaeoclimatic numerical modelling suggesting that the climate of the Black Sea became warmer and somewhat drier during the peak of the MSC in the Mediterranean [START_REF] Bartol | Flexure dur to the Messinian-Pontian sea level drop in the Black Sea[END_REF][START_REF] Murphy | A numerical study of the climate response to lowered Mediterranean sea level during the Messinian Salinity Crisis[END_REF], as shown in a scenario combining a Mediterranean Sea-level drop of 1500 m, with some water remaining in the basin. This scenario was accepted by [START_REF] Bache | A two-step process for the reflooding of the Mediterranean after the Messinian Salinity Crisis[END_REF]. Conversely, Tari et al. (this volume) interpreted a new seismic dataset and concluded to a significantly less important sea-level drop. It is to be noted that seismic profiles on the Marmara side of the Strandja Sill (i.e. in the Sea of Marmara) do not record such an erosional surface because of the overprint by the pullapart basins there post-dating MSC and post-MSC-reflooding [START_REF] Karakaş | Propagation et évolution structurale de la faille nord-anatolienne dans la région de Marmara[END_REF].

New seismic lines in the Southwestern Black Sea

The seismic profile BlaSON2-054 is the nearest from the seashore (Fig. 1B). It shows a deep palaeo-valley almost perpendicular to the coastline, up to 800 ms TWT depth and 900 m in width in its axial part and 2100 m at its largest opening on top. This palaeo-valley is filled by sediments which pinch out on its flanks (Fig. 9). Secant to this profile, the line BlaSON2-052 is almost parallel to the shoreline (Fig. 1B). It also shows a deep palaeo-valley almost perpendicular to the coastline, up to 900 ms TWT depth and 1550 m in width in its axial part and 3800 m at its largest opening on top, with the same characteristics of the sediment infil. On the northwestern edge of the palaeo-valley, this line practically crosses the Karadeniz 1 well (Figs. 1B,10A) which provides a stratigraphic calibration to seismic reflectors (Fig. 10B) as specified by [START_REF] Gillet | Messinian event in the black sea: Evidence of a Messinian erosional surface[END_REF] in their figures 9 and 11. The continuity of the erosional truncation allows one to establish that the sediments filling the palaeo-valley are Pliocene in age. The chronostratigraphic ascription of these sediments can hence be extended to those within the palaeo-valley shown by profile BlaSON2-054 (Fig. 10). The same erosional surface may also be observed in line BlaSON 2-051 (Fig. 1B), not in a cross-section view but in a somewhat oblique section (Fig. 11), being followed up to Site 381 as shown by [START_REF] Gillet | Messinian event in the black sea: Evidence of a Messinian erosional surface[END_REF] in their figure 8. There, sediments overlying the erosional surface are allocated to Pliocene as evidenced by the İ ğneada 1 well projected on the profile (Fig. 11; [START_REF] Gillet | Messinian event in the black sea: Evidence of a Messinian erosional surface[END_REF]: their figs. 9 and 10). To follow up the erosional surface up to Site 381 and, from it to Site 380 (Fig. 1B) where its overlying sediments are precisely dated [START_REF] Popescu | Pliocene and Lower Pleistocene vegetation and climate changes at the European scale: Long pollen records and climatostratigraphy[END_REF], allows to consider that this surface is the Messinian Erosional Surface (MES), as proposed by [START_REF] Gillet | Messinian event in the black sea: Evidence of a Messinian erosional surface[END_REF]. This is in agreement with the gap of Upper Miocene deposits in both the Karadeniz 1 and İğneada 1 wells [START_REF] Gillet | Messinian event in the black sea: Evidence of a Messinian erosional surface[END_REF]. In addition, the longitudinal view of this line shows a prograding sediment package overlying the MES before successive erosions belonging to Quaternary (Fig. 11). Pliocene sediments were deposited in subaqueous conditions and their progradation was probably a consequence of a fast sea-level rise after the above-mentioned sea-level fall. Such sediments may have been supplied by river transport and/or redeposited along the coastline.

Discussion

This work is the first to investigate the region of the Strandja Sill in relation to the possible impact of the MSC. It provides the opportunity to confirm the robustness of the Messinian erosion in the Black sea. Several aspects are now to be interpreted after being discussed in the light of previous studies, other hypotheses and the new information available on this area.

Robustness of the Messinian erosion in the Black Sea

In a recent paper, [START_REF] Grothe | Black Sea desiccation during the Messinian Salinity Crisis: Fact or fiction?[END_REF] questioned the Messinian age of the erosional surface in the Black Sea on the basis of a study of dinoflagellate cysts from Site 380. They concluded that the sea-level fall recorded in the Black Sea marked by the Pebbly Breccia has an older age at ca. 7 Ma. Such an assumption results from the proclaimed first appearance of Caspidinium rugosum and Galeacysta etrusca at the base of the Aragonite Unit (850.30 m) despite documented information on the underlying layers for supporting a first appearance datum. This interpretation is inaccurate with regard to our records reported above which establish the occurrence of Caspidinium rugosum and Galeacysta etrusca from 1009.36 m (Fig. 8).

Hence, the Grothe et al. ( 2014)'s hypothesis cannot be accepted and the late Messinian age of the Pebbly Breccia is still the preferred interpretation. Reliability of the calcareous nannofossils markers Triquetrorhabdulus rugosus and Ceratolithus acutus, fastly discarded by [START_REF] Grothe | Black Sea desiccation during the Messinian Salinity Crisis: Fact or fiction?[END_REF], can be re-asserted.

The significance of the Pebbly Breccia (originally called "Pebbly mudstone breccia"; [START_REF] Ross | Site 380[END_REF] is still debated. For these authors, it might have been deposited in subaqueous conditions in relation with the rapid Black Sea-level rise by marine influx. Conversely, Hsü andGiovanoli (1979-1980) assigned it to debris flows during the time of Black Sea shallowwater. However, [START_REF] Gillet | Messinian event in the black sea: Evidence of a Messinian erosional surface[END_REF], who evidenced the subaerial erosional surface referred to the MES and tentatively correlated it with the top of the Pebbly Breccia, considered that erosion did not reach the deepest parts of the Black Sea. At the light of new seismic data, Tari et al. (this volume) consider the Pebbly breccia as a mass transport complex. Their proposal that the Black Sea experienced a Messinian sea-level drop significantly less than the 1,600 m suggested by Hsü andGiovanoli (1979-1980) is not in contradiction with our observations.

Our dinoflagellate cyst record at DSDP Site 380 shows that the interval 969-841m (encompassing the Laminated carbonates, Pebbly Breccia, Aragonite and base of the Lower chalk) is sandwiched between two Mediterranean marine influxes (Fig. 8), probably documenting a higher level of the Black Sea. This interval should thus correspond to a relative lower Black Sea level as supported by higher percentages in halophytes (plants living on the shoreline: mostly Amaranthaceae-Chenopodiaceae, Caryophyllaceae, and Plumbaginaceae) within the pollen assemblage recorded at Site 380, particularly between 940 and 845 m [START_REF] Popescu | Late Miocene and early Pliocene environments in the southwestern Black Sea region from high-resolution palynology of DSDP Site 380A (leg 42B)[END_REF] her figure 3). Erosional events have occurred prior to the MSC [START_REF] Gillet | La stratigraphie oligo-miocène et la surface d'érosion messinienne en mer Noire, stratigraphie sismique haute résolution[END_REF]Tari et al., this volume). However, drier climatic conditions correspond to the interval 922-845 m, as pointed out by prevalent Asteraceae with respect to Poaceae among the herbaceous pollen content [START_REF] Popescu | Late Miocene and early Pliocene environments in the southwestern Black Sea region from high-resolution palynology of DSDP Site 380A (leg 42B)[END_REF] her figure 3). This evolution seems consistent with that simulated by [START_REF] Bartol | Flexure dur to the Messinian-Pontian sea level drop in the Black Sea[END_REF] and [START_REF] Murphy | A numerical study of the climate response to lowered Mediterranean sea level during the Messinian Salinity Crisis[END_REF] supporting an impact of the Mediterranean desiccation on the Black Sea climate. However, it is not excluded that the palaeo-valley shown in seismic profiles BlaSON2-052 and BlaSON2-054 began to be cut prior to the MSC and significantly deepened during its peak.

A marine gateway at the Strandja Sill?

The youngest marine influence on the Black Sea side has been dated close to 12 Ma at Akpınar, i.e. in the late Serravallian (early Sarmatian s.l. in the Paratethyan chronostratigraphic scale: Fig. 12; [START_REF] Vasiliev | Magnetostratigraphy and radio-isotope dating of upper Miocene-lower Pliocene sedimentary succession of the Black Sea Basin (Taman Peninsula, Russia)[END_REF]. At that time, the connection between the Eastern Paratethys and the Indian Ocean was closed according to [START_REF] Rögl | Mediterranean and Paratethys. Facts and hypotheses of an Oligocene to Miocene paleogeography (short overview)[END_REF], who considers a connection with the Mediterranean through a corridor located in northern Syria. There was no simultaneous connection between the Black and Aegean seas which, according to [START_REF] Rögl | Mediterranean and Paratethys. Facts and hypotheses of an Oligocene to Miocene paleogeography (short overview)[END_REF], was established in the area of İ stanbul later, during the Tortonian (late Sarmatian s.l. and early Meotian in the Paratethyan chronostratigraphic scale: Fig. 12; [START_REF] Vasiliev | Magnetostratigraphy and radio-isotope dating of upper Miocene-lower Pliocene sedimentary succession of the Black Sea Basin (Taman Peninsula, Russia)[END_REF]. But, such a gateway remains undocumented. The conformity of the Bakırköy Formation above the Çukurçeşme Formation and our calcareous nannofossil evidence on the southern side of the Strandja Sill support some influx of Mediterranean waters, as recorded at Avcılar and Kayabaşı. However, the available information does not support their passage to the northern side of the sill (Fig. 12), except for the late Tortonian occurrences of marine dinoflagellate cysts [START_REF] Popescu | Late Miocene and early Pliocene environments in the southwestern Black Sea region from high-resolution palynology of DSDP Site 380A (leg 42B)[END_REF] and marine diatoms [START_REF] Schrader | Quaternary through Neogene history of the Black Sea, deduced from the paleoecology of diatoms, silicoflagellates, ebridians, and chrysomonads[END_REF] in the Black shales at DSDP Site 380 as detailed above (Fig. 8). The Mediterranean marine influx evidenced in the area of the Dardanelles Strait [START_REF] Melinte-Dobrinescu | The Messinian Salinity Crisis in the Dardanelles region: Chronostratigraphic constraints[END_REF] prior to the MSC concerns the early Messinian according to the co-occurrence of the calcareous nannofossils Reticulofenestra rotaria that firstly appears within the Tortonian/Messinian boundary interval [START_REF] Raffi | Late Miocene calcareous nannofossil biostratigraphy and astrobiochronology for the Mediterranean region[END_REF], and Nicklithus amplificus that has its first occurrence at 6.84 Ma in the eastern Mediterranean [START_REF] Raffi | A review of calcareous nannofossil astrobiochronology encompassing the past 25 million years[END_REF]. Neither R. fenestra nor N. amplificus has been recorded at Avcılar and Kayabaşı, indicating that this early Messinian marine influx did not reach the region of İ stanbul. Accordingly, the data suggest that no more connection may have existed in this area between the Mediterranean and Paratethys since ca. 8 Ma, and particularly when the marine reflooding of the Mediterranean occurred at 5.46 Ma [START_REF] Bache | A two-step process for the reflooding of the Mediterranean after the Messinian Salinity Crisis[END_REF]. This is in agreement with the delayed arrival (at 5.31 Ma) of the Mediterranean micro-organisms (calcareous nannofossils, dinoflagellates, diatoms) in the southwestern Black Sea (Site 380) with respect to the marine reflooding of the Mediterranean at 5.46 Ma [START_REF] Popescu | Pliocene and Lower Pleistocene vegetation and climate changes at the European scale: Long pollen records and climatostratigraphy[END_REF][START_REF] Bache | A two-step process for the reflooding of the Mediterranean after the Messinian Salinity Crisis[END_REF]. One must thus consider another gateway for the incursion of Mediterranean waters into the Eastern Paratethys and for the reverse outflow from Paratethys into the Mediterranean. The suitable candidate is the Balkans corridor evidenced by [START_REF] Clauzon | Influence of the Mediterranean sea-level changes over the Dacic Basin (Eastern Paratethys) in the Late Neogene. The Mediterranean Lago Mare facies deciphered[END_REF], [START_REF] Popescu | Galeacysta etrusca complex, dinoflagellate cyst marker of Paratethyan influxes into the Mediterranean Sea before and after the peak of the Messinian Salinity Crisis[END_REF], [START_REF] Suc | The Messinian Salinity Crisis in the Dacic Basin (SW Romania) and early Zanclean Mediterranean -Paratethys high sea-level connection[END_REF][START_REF] Suc | Marine gateway vs. fluvial stream within the Balkans from 6 to 5 Ma[END_REF] and [START_REF] Bache | A two-step process for the reflooding of the Mediterranean after the Messinian Salinity Crisis[END_REF].

The palaeo-fluvial network

The fluvial erosion evidenced southward of Karacaköy and the overlying deltaic sediments continuing offshore in a prograding system within the Messinian valley morphology lead us to reject the suggestion of a marine gateway in this area (cf. [START_REF] Krijgsman | Rise and fall of the Paratethys Sea during the Messinian Salinity Crisis[END_REF]. In fact, the Karamandere palaeo-gorge was cut by a powerful river as a result of the drop of the Black Sea level, which is particularly evident in the offshore domain. Then, after the sea-level rise at about 5.45 Ma according to the [START_REF] Popescu | Pliocene and Lower Pleistocene vegetation and climate changes at the European scale: Long pollen records and climatostratigraphy[END_REF]'s chronology, the Karamandere palaeogorge became the outlet of this river with its delta on the shoreline. The Karamandere river provided a large quantity of pebbles, gravels and sands which were deposited in the subaqueous foreset beds (seismic line BlaSON2-051: Fig. 11) and then in the subaerial topset beds observed in the Karacaköy area. During the low sea level, this river and several others from the southwestern Black Sea should have transported large amount of coarse clastics to the deepest parts of the basin. These coarse clastics linked to the Messinian events can be potential reservoirs for hydrocarbon accumulation. Palaeo-valleys have also been observed in a 150 km-long seismic profile, extending parallel to the coastline from offshore Varna to the Borphorus Strait, that [START_REF] Nikishin | New set of seismic data for Black Sea. Black Sea & Caspian 2014 Conference[END_REF] attributed to the Messinian Crisis. Concerning the Messinian fluvial network in the area, the shift from a transverse cross-section of the Messinian valley and its sedimentary filling to a longitudinal one between the lines BlaSON-052 and BlaSON-051 can be explained by two catching different fluvial inputs. One input was probably from the Karacaköy delta as shown by profiles BlaSON-054 and BlaSON-052. The BlaSON-051 line, however, indicates yet another stronger river input probably originating from the İğneada Gulf to the North. Further field investigations are thus necessary in this area where Pliocene sediments are mapped (Fig. 1B; Ternek, 1964;[START_REF] Yurtsever | İstanbul F21[END_REF].

A fluvial network flowing from the eastern part of the present-day Marmara Sea area was evidenced during the peak of the MSC (Fig. 13B; [START_REF] Suc | The Messinian Salinity Crisis in the Northeastern Aegean -Black Sea region. 13th RCMNS Congress Naples[END_REF], which enter into the northern Aegean basin through the area of the Dardanelles Strait [START_REF] Melinte-Dobrinescu | The Messinian Salinity Crisis in the Dardanelles region: Chronostratigraphic constraints[END_REF]. The major element of this fluvial system could have been the palaeo-Sakarya River originating from the Central Anatolian Plateau (Fig. 13A). The river, which flowed towards the lowered Black Sea through the Karamandere palaeo-gorge, had an opposite course (Fig. 13B; [START_REF] Suc | The Messinian Salinity Crisis in the Northeastern Aegean -Black Sea region. 13th RCMNS Congress Naples[END_REF]. Today, a small brook, tributary of the Belgrat River, flows from the Karamandere pass (Fig. 6A). This short stream could not have cut the deep Messinian valley observed offshore. Its source is very close to a tributary of the Ergene River, which flows in an opposite course, being itself a tributary of the 480 km long Maritsa River (Fig. 13A). [START_REF] Melinte-Dobrinescu | The Messinian Salinity Crisis in the Dardanelles region: Chronostratigraphic constraints[END_REF] described at Enez a very weak Messinian fluvial cutting and a thin post-reflooding sedimentary filling, indicating that only a small river would have existed there at the time of the MSC. This suggests that the Ergene fluvial network, possibly augmented with a catchment of the Maritsa River, could have been directed towards the Black Sea. Such a river could have been responsible for the incision of the Karamandere gorge and offshore valley and subsequent deposition of the large deltaic infill. This hypothesis with the palaeo-drainage network of the area is illustrated in Figures 13B (for peak of the MSC) and 13C (for post-MSC reflooding). In a similar scenario, [START_REF] Okay | Tectonically induced Quaternary drainage diversion in the northwestern Aegean[END_REF] proposed that the palaeo-Maritsa-Ergene network flowed into the northern Marmara Sea domain prior to the Early Quaternary. We propose that, during the Late Miocene and Early Pliocene, the Maritsa-Ergene fluvial system was directed towards the Black Sea, but later progressively shifted to its present-day course as a result of the uplifting Strandja Sill [START_REF] Sakınç | Palaeogeographical evolution of the Thrace Neogene Basin and the Tethys-Paratethys relations at northwestern Turkey (Thrace). Palaeogeogr., Palaeoclimatol[END_REF][START_REF] Sakınç | Messinian crisis: What happened around the northeastern Aegean?[END_REF] and, probably, effect of the Mediterranean glacio-eustatic lowstands during the Quaternary (Fig. 13A).

Conclusion

The two sides of the Strandja Sill were investigated with the aim to specify its role in the possible connection between the Eastern Paratethys and Mediterranean during the period encompassing the MSC. Referring to the controversy about a proposed sea-level fall of the Black Sea before 7 Ma [START_REF] Grothe | Black Sea desiccation during the Messinian Salinity Crisis: Fact or fiction?[END_REF], our re-visited dinoflagellate cyst records demonstrate that the Messinian Salinity Crisis significantly impacted the Black Sea, as expressed by a well-marked fluvial erosion. Our effort involved both new and existing observations and biostratigraphic age determinations in the onshore and offshore Black Sea areas in order to reconstruct the history of the sill during the whole Neogene, which is summarized in the synthesis displayed in Figure 12. Only a connection at around 8 Ma may have existed, pointed out by Paratethyan molluscs which arrived on the Marmara side and dinoflagellate cysts which reached the Black Sea Site 380. At the time of the peak of the MSC, two opposite fluvial networks drained the region, which resulted in significant incisions. On the basis of these findings, we conclude that the Strandja Sill was not the gateway for the Paratethyan organisms that characterize any of the three Lago Mare events now well identified in the Mediterranean [START_REF] Couto | Lago Mare and the Messinian Salinity Crisis: Evidences from the Alboran Sea (S. Spain)[END_REF]. The marine corridor evidenced in the Balkans [START_REF] Clauzon | Influence of the Mediterranean sea-level changes over the Dacic Basin (Eastern Paratethys) in the Late Neogene. The Mediterranean Lago Mare facies deciphered[END_REF][START_REF] Popescu | Galeacysta etrusca complex, dinoflagellate cyst marker of Paratethyan influxes into the Mediterranean Sea before and after the peak of the Messinian Salinity Crisis[END_REF][START_REF] Bache | A two-step process for the reflooding of the Mediterranean after the Messinian Salinity Crisis[END_REF][START_REF] Suc | Marine gateway vs. fluvial stream within the Balkans from 6 to 5 Ma[END_REF] was the appropriate gateway for late Messinian -early Zanclean water, which allowed crossed exchanges of Mediterranean and Eastern Paratethys organisms. The reconstructed erosion-sedimentation process of the southwestern Black Sea margin during the time-interval between 6 and 5 Ma constitutes a comprehensive model in an area intensively explored for hydrocarbons. [START_REF] Young | Chapter 9: Neogene[END_REF][START_REF] Yurtsever | İstanbul F21[END_REF][START_REF] Türkecan | 1/500.000 scale geological maps of Turkey, İ stanbul[END_REF] with the Black Sea offshore wells and location of the BlaSON seismic profiles presented in this paper. a -b, Geological section through the Strandja Sill shown in Figure 2; Localities: 1, Beykent; 2, Avcılar; 3, Kayabaşı; 4, Akpınar; 5, Kocayemiş. WBSF, West Black Sea Fault; TEFZ, Thrace-Eskişehir Fault Zone. The green box corresponds to the geological map of the Karacaköy area shown in Figure 6A.

Fig. 1 .

 1 Fig. 1. Location maps. A, Location of the study area. Palaeogeography of the Central and Eastern Paratethys at the latest Miocene is from Krijgsman et al. (2010). B, Simplified geological map of the Strandja Sill area (from: Çağlayan and Yurtsever, 1998; Yurtsever and Çağlayan, 2002; Türkecan and Yurtsever, 2002) with the Black Sea offshore wells and location of the BlaSON seismic profiles presented in this paper. a -b, Geological section through the Strandja Sill shown in Figure 2; Localities: 1, Beykent; 2, Avcılar; 3, Kayabaşı; 4, Akpınar; 5, Kocayemiş. WBSF, West Black Sea Fault; TEFZ, Thrace-Eskişehir Fault Zone. The green box corresponds to the geological map of the Karacaköy area shown in Figure 6A.

Fig. 2 .

 2 Fig.2. Cross-section a -b through the Strandja Sill according to the geological map of[START_REF] Yurtsever | İstanbul F21[END_REF].

Fig. 3 .

 3 Fig. 3. The Beykent section. A, General view. B, Lithology and formations. C, Detail of pebbles. D, Clayey lens within the pebbles. E, Zoom on the Çukurçeşme and Bakırköy formations.

Fig. 4 .

 4 Fig. 4. The Avcılar section. 1 to 6, samples.A, Lower part of the section. B, Upper part of the section.

Fig. 5 .

 5 Fig. 5. The Akpınar quarry.A, General view of the section. B, Zoom on the base of the section with location of samples 1 and 2. C, Zoom on the top of the section with location of samples 3 and 4.

Fig. 6 .

 6 Fig. 6. The Karacaköy area. A, Simplified geological map at scale 1/100,000 from Çağlayan and Yurtsever (1998). 1, Exposed surface section from the Thrace Basin; 2, Exposed section in the descent to the North of the Karamandere pass; 3, Quarry westward of Karacaköy; 4, Quarry between Karacaköy and Ormanlı. B, Section observed at site 1 showing a quartzite seam crossing the Ergene Formation at the topmost of the Thrace Basin; C, Cross-bedded fluvial sands of the Ergene Formation at site 2; D, Sands and gravels of the Ergene Formation worked in the quarry of site 3; E, Sands and gravels of the Ergene Formation worked in the quarry of site 4; F, Silicified tree trunks from the Ergene Formation at site 4.

Fig. 7 .

 7 Fig. 7. Geology of the northern side of the Karamandere pass. A, East-West panoramic photograph (with location of photograph of Figure B). B, View showing deposits of the Ergene Formation nested within the basement rocks at the Karamandere pass. C, Interpreted geology and geomorphology of the panoramic view, with respect to the geological map of Çağlayan and Yurtsever (1998).

Fig. 8 .

 8 Fig. 8. Dinoflagellate cyst content from the interval 840.07 -1019.85 m of DSDP Site 380.

Fig. 9 .

 9 Fig. 9. Seismic profile BlaSON2-054. A, Non interpreted profile. B, Interpreted profile.

Fig. 10 .

 10 Fig. 10. Seismic profile BlaSON2-052. A, Non interpreted profile with location of the Karadeniz 1 well. B, Interpreted profile with stratigraphic subdivision of the Karadeniz 1 well.

Fig. 12 .

 12 Fig. 12. Interpreted onland stratigraphic successions on both sides of the Strandja Sill. Reference to the Paratethys Stratigraphy is done for the time interval corresponding to its more or less continuous isolation, i.e. from the early Sarmatian s.l. (= mid-Serravallian) to Kimmerian (= Zanclean). M, Mammals; N, Calcareous nannofossils; Mo, Molluscs; D, Dinoflagellate cysts. Double arrow: possible marine connection. Hatched areas: sedimentary gaps.

Fig. 13 .

 13 Fig. 13. Reconstructed geography and fluvial network of the Strandja Sill region at the end of Messinian and beginning of Zanclean with comparison to the present-day hydrography of the region. A, Present-day main rivers. The map was created using the GeoMapApp©System http://www.geomapapp.org/ (Ryan et al., 2009). B, Palaeogeography during the peak of the Messinian Salinity Crisis (5.5 Ma). C, Palaeogeography after the marine reflooding (5.31 Ma).

  at 840.07 m, i.e. 24.43 m above the Pebbly Breccia (Fig.8;[START_REF] Popescu | Pliocene and Lower Pleistocene vegetation and climate changes at the European scale: Long pollen records and climatostratigraphy[END_REF]. Selenopemphix nephroides (1009.36 m, 976.99 m), Brigantedinium spp. (840.07 m). This study documents the occurrence of Galeacysta etrusca from 1009.36 m with other typical Paratethyan dinoflagellate cysts recorded from 1019.85 m. The presence of Spiniferites validus between 976.99 and 1019.85 m allows to ascribe an age of ca. 9.2 to 8.1 Ma (late Tortonian) to this interval (S. validus Zone:

	etrusca (1009.36 m, 1008.68 m, 846.16 m, 840.07 m) (Pl. 1, Figs. 2a-2b) 2 , Caspidinium
	rugosum (1008.68 m, 849.10 m, 846.16 m, 841.91 m), Spiniferites cruciformis (1008.68
	m, 846.16 m, 841.91 m, 840.07 m), Impagidinium caspienense (1009.36 m, 1008.68 m),
	I. globosum (840.07 m), Millioudodinium punctatum (840.07 m), Spiniferites bentorii
	pannonicus (1008.68 m, 976.99 m), S. bentorii granulatus (1018.85 m, 1017.82 m,
	976.99 m), S. maisensis (976.99 m, 840.07 m), S. tihanyensis (1019.85 m, 1017.82 m,
	976.99 m, 840.07 m), and S. validus (1019.85 m, 1017.82 m, 1008.68 m, 976.99 m);
	-and marine species: Achomosphaera andalusiensis (1019.85 m, 1008.68 m, 976.99 m,
	840.07 m), Hystricokolpoma spp. (976.99 m, 840.07 m), Impagidinium patulum (976.99
	m, 840.07 m), I. sphaericum (840.07 m), I. aculeatum (840.07 m), Impagidinium spp.
	(1009.36 m, 1008.68 m, 976.99 m, 840.07 m), Lingulodinium machaerophorum
	(1019.85 m, 1008.68 m, 976.99 m), Operculodinium centrocarpum (976.99 m, 840.07
	m), Polysphaeridium zoharii (976.99 m, 840.07 m), Spiniferites mirabilis (1008.68 m,
	976.99 m), S. membranaceous (976.99 m), S. bentorii (1008.68 m, 976.99 m, 840.07 m),
	S. hyperacanthus (1010.53 m, 976.99 m), S. bulloideus (1019.85 m, 1010.53 m, 1009.36
	m, 976.99 m), S. ramosus (1018.85 m, 1009.36 m, 1008.68 m, 976.99 m, 840.07 m),
	Eleven samples have been re-examined for the dinoflagellate content at 1019.85 m, 1018.85
	m, 1017.82 m, 1010.53 m, 1009.36 m, 1008.68 m, 976.99 m, 849.10 m, 846.16 m, 841.91 m,
	and 840.07 m.
	They provided (Fig. 8):
	-Paratethyan species: Spiniferites balcanicus (841.91 m, 840.07 m) (Pl. 1, Figs. 6a-6b),
	Romanodinium areolatum (1009.36 m, 840.07 m) (Pl. 1, Figs. 4a-4b), Galeacysta

Depths are expressed in metres below sea floor.

Because of close morphologies, Spiniferites balcanicus Baltes 1971, Romanodinium areolatum Baltes 1971 and Galeacysta etrusca Corradini and Biffi 1988 have been grouped in the Galeacysta etrusca Complex[START_REF] Popescu | Galeacysta etrusca complex, dinoflagellate cyst marker of Paratethyan influxes into the Mediterranean Sea before and after the peak of the Messinian Salinity Crisis[END_REF].

Acknowledgements

The onland investigations were realized during several field trips within the frame of the ANR EGEO Project. Seismic profiles were acquired during the BlaSON2 (Ifremer) survey on the R/V "Le Suroît". We particularly thank the reviewers of this manuscript: G. Tari for his constructive comments and an anonymous one who, in addition, made us benefiting from his appreciation of the field trip in Sept. 2013 and his knowledge of the DSDP Site 380. References