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The MagellanPlus workshop “BlackGate” addressed fundamental questions concerning the dynamic evolution of the Mediterranean–Black Sea (MBS) gateway and its palaeoenvironmental consequences. This gateway drives the Miocene–Quaternary circulation patterns in the Black Sea and governs its present status as the world's largest example of marine anoxia. The exchange history of the MBS gateway is poorly constrained because continuous Pliocene–Quaternary deposits are not exposed on land adjacent to the Black Sea or northern Aegean. Gateway exchange is controlled by climatic (glacio-eustatic-driven sea-level fluctuations) and tectonic processes in the catchment as well as tectonic propagation of the North Anatolian Fault Zone (NAFZ) in the gateway area itself. Changes in connectivity trigger dramatic palaeoenvironmental and biotic turnovers in both the Black Sea and Mediterranean domains. Drilling a Messinian to Holocene transect across the MBS gateway will recover high-amplitude records of continent-scale hydrological changes during glacial–interglacial cycles and allow us to reconstruct marine and freshwater fluxes, biological turnover events, deep biospheric processes, subsurface gradients in primary sedimentary properties, patterns and processes controlling anoxia, chemical perturbations and carbon cycling, growth and propagation of the NAFZ, the timing of land bridges for Africa and/or Asia–Europe mammal migration, and the presence or absence of water exchange during the Messinian salinity crisis. During thorough discussions at the workshop, three key sites were selected for potential drilling using a mission-specific platform (MSP): one on the Turkish margin of the Black Sea (Arkhangelsky Ridge, 400 m b.s.f., metres below the seafloor), one on the southern margin of the Sea of Marmara (North İmrali Basin, 750 m b.s.f.), and one in the Aegean (North Aegean Trough, 650 m b.s.f.). All sites target Quaternary oxic–anoxic marl–sapropel cycles. Plans include recovery of Pliocene lacustrine sediments and mixed marine–brackish Miocene sediments from the Black Sea and the Aegean. MSP drilling is required because the JOIDES Resolution cannot pass under the Bosporus bridges. The wider goals are in line with the aims and scope of the International Ocean Discovery Program (IODP) “2050 Science Framework: Exploring Earth by Scientific Ocean Drilling” and relate specifically to the strategic objectives “Earth's climate system”, “Tipping points in Earth's history”, and “Natural hazards impacting society”.

The MagellanPlus workshop "BlackGate"addressed fundamental questions concerning the dynamic evolution of the Mediterranean-Black Sea (MBS) gateway and its palaeoenvironmental consequences. This gateway drives the Miocene-Quaternary circulation patterns in the Black Sea and governs its present status as the world's largest example of marine anoxia. The exchange history of the MBS gateway is poorly constrained because continuous Pliocene-Quaternary deposits are not exposed on land adjacent to the Black Sea or northern Aegean. Gateway exchange is controlled by climatic (glacio-eustatic-driven sea-level fluctuations) and tectonic processes in the catchment as well as tectonic propagation of the North Anatolian Fault Zone (NAFZ) in the gateway area itself. Changes in connectivity trigger dramatic palaeoenvironmental and biotic turnovers in both the Black Sea and Mediterranean domains. Drilling a Messinian to Holocene transect across the MBS gateway will recover high-amplitude records of continent-scale hydrological changes during glacial-interglacial cycles and allow us to reconstruct marine and freshwater fluxes, biological turnover events, deep biospheric processes, subsurface gradients in primary sedimentary properties, patterns and processes controlling anoxia, chemical perturbations and carbon cycling, growth and propagation of the NAFZ, the timing of land bridges for Africa and/or Asia-Europe mammal migration, and the presence or absence of water exchange during the Messinian salinity crisis. During thorough discussions at the workshop, three key sites were selected for potential drilling using a mission-specific platform (MSP): one on the Turkish margin of the Black Sea (Arkhangelsky Ridge, 400mb.s.f., metres below the seafloor), one on the southern margin of the Sea of Marmara (North Imrali Basin, 750mb.s.f.), and one in the Aegean (North Aegean Trough, 650mb.s.f.). All sites target Quaternary oxic-anoxic marl-sapropel cycles. Plans include recovery of Pliocene lacustrine sediments and mixed marine-brackish Miocene sediments from the Black Sea and the Aegean. MSP drilling is required because the JOIDES Resolution cannot pass under the Bosporus bridges. The wider goals are in line with the aims and scope of the International Ocean Discovery Program (IODP) "2050 Science Framework: Exploring Earth by Scientific Ocean Drilling"and relate specifically to the strategic objectives "Earth's climate system", "Tipping points in Earth's history", and "Natural hazards impacting society".

International Continental Scientific Drilling Program (ICDP) drilled a complete succession of the lacustrine sedi ment sequence deposited during the last 500000 years in Lake Van Eastern Anatolia (Turkey). Based on a detailed seismic site survey two sites at a water depth of up to 360 m were drilled in summer 2010 and cores were retrieved from sub lake floor depths of 140 m (Northern Basin) and 220 m (Ahlat Ridge). To obtain a complete sedimentary section the two sites were multiple cored in order to investigate the pale oclimate history of a sensitive semi arid region between the Black Caspian and Mediterranean seas. Further scientific goals of the PALEOVAN project are the reconstruction of earthquake activity as well as the temporal spatial and compositional evolution of volcanism as reflected in the dep osition of tephra layers. The sediments host organic matter from different sources and hence composition which will be unravelled using biomarkers. Pathways for migration of con tinental and mantle derived noble gases will be analyzed in pore waters. Preliminary 40Ar/39Ar single crystal dating of tephra layers and pollen analyses suggest that the Ahlat Ridge record encompasses more than half a million years of paleoclimate and volcanic/geodynamic history providing the longest continental record in the entire Near East to date.

Lake Van sediment cores from the Ahlat Ridge and Northern Basin drill sites of the ICDP project PALEOVAN contain a wealth of information about past environmental processes. The sedimentary sequence was dated using climatostratigraphic alignment, varve chronology, tephrostratigraphy, argon-argon single-crystal dating, radiocarbon dating, magnetostratigraphy, and cosmogenic nuclides. Based on the lithostratigraphic framework, the different age constraints are compiled and a robust and precise chronology of the 600,000 year-old Lake Van record is constructed. Proxy records of total organic carbon content and sediment color, together with the calcium/potassium-ratios and arboreal pollen percentages of the 174-meter-long Ahlat Ridge record, mimic the Greenland isotope stratotype (NGRIP). Therefore, the proxy records are systematically aligned to the onsets of interstadials reflected in the NGRIP or synthesized Greenland ice-core stratigraphy. The chronology is constructed using 27 age control points derived from visual synchronization with the GICC05 timescale, an absolutely-dated speleothem record (e.g., Hulu, Sanbao, Linzhu cave) and the Epica Dome C timescale. In addition, the uppermost part of the sequence is complemented with four ages from Holocene varve chronology and two calibrated radiocarbon ages. Furthermore, nine argon-argon ages and a comparison of the relative paleointensity record of the magnetic field with reference curve PISO-1500 confirm the accuracy of the age model. Also the identification of the Laschamp event via measurements of 10Be in the sediment confirms the presented age model. The chronology of the Ahlat Ridge record is transferred to the 79-meter-long event-corrected composite record from the Northern Basin and supplemented by additional radiocarbon dating on organic marco-remains. The basal age of the Northern Basin record is estimated at ~90 ka. The variations of the time series of total organic carbon content, the Ca/K ratio, and the arboreal pollen percentages illustrate that the presented chronology and paleoclimate data are suited for reconstructions and modeling of the Quaternary and Pleistocene climate evolution in the Near East at millennial timescales. Furthermore, the chronology of the last 250 kyr can be used to test other dating techniques.

International Continental Scientific Drilling Program(ICDP) drilled a complete succession of the lacustrine sedimentsequence deposited during the last ~500,000 years inLake Van, Eastern Anatolia (Turkey). Based on a detailedseismic site survey, two sites at a water depth of up to 360 mwere drilled in summer 2010, and cores were retrieved fromsub-lake-floor depths of 140 m (Northern Basin) and 220 m(Ahlat Ridge). To obtain a complete sedimentary section, thetwo sites were multiple-cored in order to investigate the paleoclimatehistory of a sensitive semi-arid region between theBlack, Caspian, and Mediterranean seas. Further scientificgoals of the PALEOVAN project are the reconstruction ofearthquake activity, as well as the temporal, spatial, andcompositional evolution of volcanism as reflected in the depositionof tephra layers. The sediments host organic matterfrom different sources and hence composition, which will beunravelled using biomarkers. Pathways for migration of continentaland mantle-derived noble gases will be analyzed inpore waters. Preliminary 40Ar/39Ar single crystal dating oftephra layers and pollen analyses suggest that the AhlatRidge record encompasses more than half a million years ofpaleoclimate and volcanic/geodynamic history, providingthe longest continental record in the entire Near East todate

The MARMESONET cruise is part of the Marmara Demonstration Mission Program supported by ESONET Network of Excellence (European Seafloor Observatory Network), within the 6th European Framework Programme. Main partners are: Ifremer, CNRS/CEREGE, Istanbul Technical University, TUBITAK, Institute of Marine Science and Technology of Dokuz Eylül Universitesi (Izmir), INGV (Rom) and ISMAR (Bologna). Marmesonet is also the follow-on of the Franco-Turk collaborative programme that resulted in numerous cruises in the Sea of Marmara since 2000. The objectives of the MARMESONET cruise were: 1) to study the relationship between fluids and seismicity along the Sea of Marmara fault system ; 2) to carryout site surveys prior to the implementation of permanent seafloor observatories in the Marmara Sea through ESONET. The cruise is divided in 2 parts: Leg I (from november 4th to november 25th, 2009), mainly dedicated to: i) the high resolution bathymetry at potential sites of interest for future permanent instrumentation using the Autonomous Unmanned Vehicle (AUV)Asterx of Ifremer/Insu ; ii) the systematic mapping of the gas emissions sites on the Marmara seafloor ; iii) the deployment of the Bubble Observatory Module (BOB) in the Çinarçik basin. Leg II (from november 28th november to december 14th, 2009), for 3D, High Resolution Seismic imagery of the fluid conduits below the observatory site planned at the Western High. The present report only concerns Leg I. A total of 19 dives were completed during Leg I: 16 with the multibeam echosounder SIMRAD EM2000 (200 kHz), among which 12 were successful and 4 failed ;3 with the CHIRP sédiment penetrator (1 test dive and 2 operational, both were unfortunately with early stop recording). Main results are: The absence of recent, visible deformation on the segment south of Istanbul. Wether or not this segment is locked or creeping remains an open question. The site south of Istanbul thus requires a massive effort to assess the deformation, particularly through submarine geodesy and piezometry. The plausible presence of a 4 km, right-lateral offset on the Western High, between N30 oriented structures related to cold seeps. Gas emission sites are systematically related to zones of High reflectivity mapped on the AUV imagery AUV imagery reveals the traces of intensive, human activity, which shows the necessity to ensure the security of the future cables by enforcing a clearance area Last but not least, the exact position of the future observatories is now established, at the Central High and at the Western High sites., La campagne constitue l’une des missions de démonstration soutenues par ESONET. Elle résulte d’un partenariat entre l’Ifremer, le CNRS, l’INSU, l’Université Technique d’Istanbul, l’Institut des Sciences Marines d’Izmir, le CNR-ISMAR (Bologne) et l’INGV (Rome). La plupart des objectifs du premier leg de la campagne Marmesonet, du 4 au 25 novembre 2009, ont été atteints, grâce à trois facteurs principaux: i) la météo exceptionnellement favorable ; ii) la bienveillance des garde-côtes de la Marine Turque ; iii) le professionnalisme des équipes (équipage et sédentaires)

International audience; Earthquake scarps associated with recent historical events have been found on the floor of the Sea of Marmara, along the North Anatolian Fault (NAF). The MARMARASCARPS cruise using an unmanned submersible (ROV) provides direct observations to study the fine-scale morphology and geology of those scarps, their distribution, and geometry. The observations are consistent with the diversity of fault mechanisms and the fault segmentation within the north Marmara extensional step-over, between the strike-slip Ganos and Izmit faults. Smaller strike-slip segments and pull-apart basins alternate within the main step-over, commonly combining strike-slip and extension. Rapid sedimentation rates of 1?3 mm/yr appear to compete with normal faulting components of up to 6 mm/yr at the pull-apart margins. In spite of the fast sedimentation rates the submarine scarps are preserved and accumulate relief. Sets of youthful earthquake scarps extend offshore from the Ganos and Izmit faults on land into the Sea of Marmara. Our observations suggest that they correspond to the submarine ruptures of the 1999 Izmit (Mw 7.4) and the 1912 Ganos (Ms 7.4) earthquakes. While the 1999 rupture ends at the immediate eastern entrance of the extensional Cinarcik Basin, the 1912 rupture appears to have crossed the Ganos restraining bend into the Sea of Marmara floor for 60 km with a right-lateral slip of 5 m, ending in the Central Basin step-over. From the Gulf of Saros to Marmara the total 1912 rupture length is probably about 140 km, not 50 km as previously thought. The direct observations of submarine scarps in Marmara are critical to defining barriers that have arrested past earthquakes as well as defining a possible segmentation of the contemporary state of loading. Incorporating the submarine scarp evidence modifies substantially our understanding of the current state of loading along the NAF next to Istanbul. Coulomb stress modeling shows a zone of maximum loading with at least 4?5 m of slip deficit encompassing the strike-slip segment 70 km long between the Cinarcik and Central Basins. That segment alone would be capable of generating a large-magnitude earthquake (Mw 7.2). Other segments in Marmara appear less loaded.

The MARMESONET cruise is part of the Marmara Demonstration Mission Program supported by ESONET Network of Excellence (European Seafloor Observatory Network), within the 6th European Framework Programme. Main partners are: Ifremer, CNRS/CEREGE, Istanbul Technical University, TUBITAK, Institute of Marine Science and Technology of Dokuz Eylül Universitesi (Izmir), INGV (Rom) and ISMAR (Bologna). Marmesonet is also the follow-on of the Franco-Turk collaborative programme that resulted in numerous cruises in the Sea of Marmara since 2000. The objectives of the MARMESONET cruise were: 1) to study the relationship between fluids and seismicity along the Sea of Marmara fault system ; 2) to carryout site surveys prior to the implementation of permanent seafloor observatories in the Marmara Sea through ESONET. The cruise is divided in 2 parts: Leg I (from november 4th to november 25th, 2009), mainly dedicated to: i) the high resolution bathymetry at potential sites of interest for future permanent instrumentation using the Autonomous Unmanned Vehicle (AUV)Asterx of Ifremer/Insu ; ii) the systematic mapping of the gas emissions sites on the Marmara seafloor ; iii) the deployment of the Bubble Observatory Module (BOB) in the Çinarçik basin. Leg II (from november 28th november to december 14th, 2009), for 3D, High Resolution Seismic imagery of the fluid conduits below the observatory site planned at the Western High. The present report only concerns Leg I. A total of 19 dives were completed during Leg I: 16 with the multibeam echosounder SIMRAD EM2000 (200 kHz), among which 12 were successful and 4 failed ;3 with the CHIRP sédiment penetrator (1 test dive and 2 operational, both were unfortunately with early stop recording). Main results are: The absence of recent, visible deformation on the segment south of Istanbul. Wether or not this segment is locked or creeping remains an open question. The site south of Istanbul thus requires a massive effort to assess the deformation, particularly through submarine geodesy and piezometry. The plausible presence of a 4 km, right-lateral offset on the Western High, between N30 oriented structures related to cold seeps. Gas emission sites are systematically related to zones of High reflectivity mapped on the AUV imagery AUV imagery reveals the traces of intensive, human activity, which shows the necessity to ensure the security of the future cables by enforcing a clearance area Last but not least, the exact position of the future observatories is now established, at the Central High and at the Western High sites., La campagne constitue l’une des missions de démonstration soutenues par ESONET. Elle résulte d’un partenariat entre l’Ifremer, le CNRS, l’INSU, l’Université Technique d’Istanbul, l’Institut des Sciences Marines d’Izmir, le CNR-ISMAR (Bologne) et l’INGV (Rome). La plupart des objectifs du premier leg de la campagne Marmesonet, du 4 au 25 novembre 2009, ont été atteints, grâce à trois facteurs principaux: i) la météo exceptionnellement favorable ; ii) la bienveillance des garde-côtes de la Marine Turque ; iii) le professionnalisme des équipes (équipage et sédentaires)

A new late Neogene proboscidean site, Cebara has been currently discovered by the local fossil collector Vinko Ljubas south of Tomislavgrad in Bosnia and Hercegovina. It is located in one ~40 m deep, ~20 m high and ~17 m wide incision of the escarpment opened during quarry exploitation at the southwestern margin of a typical Dinaride karst polje termed Duvanjsko polje. The latter represents a ~240 km2 large and NW-SE striking intra-mountainous basin that was initiated in the early Miocene (~17 Ma) as the eastern part of the Livno-Tomislavgrad basin. Herein two sedimentary cycles accumulated more than 2500 m of coal bearing lacustrine deposits until the latest Miocene (~6 Ma) therein. The posterior wall of distally narrowing incision shows coarsening upward succession of clays, fluvial gravels and block-breccia including up to 5 m diameter boulders developed through reoccurring cave roof collapses. Upward the incision in unroofed passing into a ~35 m wide and ~10 m deep funnel-shaped doline. The logged succession is 10 m thick with the base covered by debris and top not reachable at present outcrop conditions. It comprise two units of equal thickness. The lower one is characterized by deposition of brownish clay that can include sand lenses and/or laterally grade to block-breccia. Beyond that up to 1 m thick sand, gravel and boulder intercalations are present. The upper unit is composed of two conglomerate packages both topped by cave-in breccia. The lower gravel shows through- and cross-bedding and at its base operculi accumulations of freshwater snail Bythinia occur supporting the inference of riverine and/or lacustrine origin of the sediment. The bone bed interval is about 1.5 m thick and marks the middle part of the lower unit. The fossil bones, tusks and teeth oriented horizontally to the bedding plane, are disarticulated and concentrated in three 10 to 30 cm thick horizons. The lower one appears on top of one 30 cm thick gravel bed, the other two mark lower and upper part of one 90 cm thick sandy layer. Strongly increased magnetic susceptibility values (>100 x 10-6 SI) detects the black color of the bones and matrix sediments as containing iron- bearing minerals. The inspection of up to now available fossil remains allows their tentative classification as Anancus arvernensis (Croizet & Jobert 1928) representing a tetralophodon gomphothere characterized by two oversized straightened tusks in the upper jaw and a body- size of today's elephant. This European gomphothere has the peak distribution in the late Pliocene, and the stratigraphic range from the latest Miocene MN 11 to the early Pleistocene MN 17. Although the stratigraphic data does not allow a precise inference of the age yet, the lithostratigraphic evidence supports the correlation with the Pliocene and/or Pleistocene in a phase post-dating the Miocene long-lived lake conditions.