This file was created by the TYPO3 extension publications --- Timezone: CEST Creation date: 2026-05-14 Creation time: 05:31:43 --- Number of references 57 article Kearney2025 Article 2025 10.1016/j.quascirev.2024.109165 Quaternary Science Reviews 352 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85216572198&doi=10.1016%2fj.quascirev.2024.109165&partnerID=40&md5=9745bf6100316fbf1caafeaff2ca8d7e Cited by: 2; All Open Access, Hybrid Gold Open Access Rebecca J. Kearney Jeremy Goff Victoria Smith Markus J. Schwab Yavuz Özdemir Özgür Karaoǧlu Matthew Thirlwall Dan N. Barfod Oona Appelt Christina Günter Jan Fietzke Nadine Pickarski Ina Neugebauer Rik Tjallingii Achim Brauer article Pickarski2023 Article 2023 10.1038/s43247-023-00827-0 Communications Earth and Environment 4 1 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85159680680&doi=10.1038%2fs43247-023-00827-0&partnerID=40&md5=139a30871657284ed406c2ab4fd9802a Cited by: 5; All Open Access, Gold Open Access Nadine Pickarski Ola Kwiecien Thomas Litt article Steinhoff20221191 Article 2022 10.1017/RDC.2022.34 Radiocarbon 64 1191 – 1207 5 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85140070520&doi=10.1017%2fRDC.2022.34&partnerID=40&md5=45a26e518bdae10d6c6cbe0b28ec7e27 Cited by: 2; All Open Access, Hybrid Gold Open Access Christoph Steinhoff Nadine Pickarski Thomas Litt Irka Hajdas Caroline Welte Peter Wurst David Kühne Andreas Dolf Maximilian Germer Jens Kallmeyer article Stockhecke2021 Article 2021 10.1016/j.palaeo.2021.110535 Palaeogeography, Palaeoclimatology, Palaeoecology 577 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85109014988&doi=10.1016%2fj.palaeo.2021.110535&partnerID=40&md5=bf804fb544f148d02a666ad59bfb3ded Cited by: 11; All Open Access, Green Open Access, Hybrid Gold Open Access Mona Stockhecke Achim Bechtel Francien Peterse Typhaine Guillemot Carsten J. Schubert article Guillemot2019 Article 2019 10.1016/j.quascirev.2019.105997 Quaternary Science Reviews 225 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85073726369&doi=10.1016%2fj.quascirev.2019.105997&partnerID=40&md5=40dacbae3718a82687a32fbe7cd8a9c5 Cited by: 8 T. Guillemot M. Stockhecke A. Bechtel S.N. Ladd D.B. Nelson C.J. Schubert article McCormack2019167 Oxygen and carbon isotope (δ 18 O and δ 13 C) data from bulk carbonates are widely applied proxies for temperature, the precipitation/evaporation ratio and productivity in lacustrine palaeohydrology and palaeoclimatology. In case of the terminal and alkaline Lake Van, however, previous studies have shown that bulk oxygen isotope compositions are in disagreement with other proxies when interpreted in a conventional manner. Similarly, the reports on the nature and the timing and site of carbonate precipitation in Lake Van are inconsistent. This study provides evidence on the mineralogy (X-ray powder diffraction analysis, scanning electron microscope imaging, confocal Raman microscopy, electron microprobe analysis) and isotope composition (δ 18 O and δ 13 C) of non-skeletal carbonate minerals in a Lake Van sedimentary profile spanning the last ca. 150 kyr. Carbonate phases present in the sediment include aragonite, low-Mg calcite, and calcian dolomite. Dolomite forms as an early diagenetic phase and occurs episodically in high concentrations driving the bulk isotope record towards the higher dolomite δ 18 O and varying δ 13 C values. Aragonite and low-Mg calcite precipitate in the surface water and are present in the sediments in varying amounts (relative aragonite to calcite content for dolomite-poor samples Ar/(Ar + Cc) of 93 to 41 wt%). In an attempt to explain this variation, we revised a precipitation model based on annually laminated sediments containing both aragonite and calcite spatially separated in light and dark coloured laminae, respectively. According to our model, spring calcite precipitation, under close-to-freshwater conditions, is followed by evapoconcentration-driven aragonite precipitation in late summer. The precipitation of these carbonate polymorphs from chemically differing surface waters (i.e. freshwater-influenced and evapoconcentrated) leads to distinctly different oxygen and carbon isotope signatures between sedimentary penecontemporaneous aragonite and calcite. The δ 18 O and δ 13 C values of aragonite relative to calcite are significantly higher by several per mille than inferred from aragonite-calcite fractionation factors alone, suggesting that the generalised assumption of sedimentary coeval calcite and aragonite precipitating from water with the same isotopic composition is flawed. The here proposed revised hydrologically-separated carbonate precipitation model is not only taking (i) differences in the isotopic fractionation between carbonate minerals into account, but also (ii) considering the hydrological conditions and the processes favouring the precipitation of a given mineral and ultimately controlling its isotopic composition. If mixed mineralogies are present, this mineralogy-specific approach has the potential of refining environmental reconstructions and reconciling apparently equivocal interpretations of different proxy records. © 2019 The Authors 2019 English 00092541 10.1016/j.chemgeo.2019.03.014 Chemical Geology 513 Elsevier B.V. 167-183 Department of Geology, Mineralogy and Geophysics, Ruhr University Bochum, Bochum, 44801, Germany; Alfred Wegener Institut, Helmholtz Zentrum für Polar und Meeresforschung, Bremerhaven, 27570, Germany Calcite; Carbon; Carbonation; Electron probe microanalysis; Isotopes; Lakes; Oxygen; Refining; Repair; Scanning electron microscopy; Sedimentology; Sediments; Water; X ray powder diffraction, Carbonate precipitation; Confocal Raman microscopy; Diagenetics; Environmental reconstruction; Isotopic fractionations; Lake vans; Oxygen isotope composition; Palaeoenvironmental reconstruction, Carbonate minerals, aragonite; calcite; carbon isotope; carbonate; diagenesis; dolomite; isotopic composition; lacustrine deposit; mineralogy; oxygen isotope; paleoenvironment; reconstruction; sediment chemistry, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-85063198079&doi=10.1016%2fj.chemgeo.2019.03.014&partnerID=40&md5=bd89ff8a1867259f7e458b1780cf340d cited By 18 J. McCormack G. Nehrke N. Jöns A. Immenhauser O. Kwiecien article North2018119 Ancient lake sediments provide opportunities to reconstruct aquatic ecosystems during previous interglacials. In the summer of 2010, the ICDP project PALEOVAN drilled a complete succession of the lacustrine sedimentary sequence deposited during the last ~600,000 years in Lake Van, eastern Anatolia (Turkey). Previous palaeolimnological analysis of the Lake Van sediment record has shown diatoms to be absent over most of the sequence apart from a short interval during the Holocene. Here, we demonstrate the preservation of additional fragmentary diatom records during Marine Isotope Stage (MIS) 7 (243,000–191,000 years ago; Lisiecki and Raymo in Paleoceanography 20:PA1003, 2005; Jouzel et al. in Science 317:793–796, 2007) and MIS5e (130,000–116,000 years ago; Lisiecki and Raymo 2005; Jouzel et al. 2007), each spanning no more than a few thousand years. Although brief, the presence of contrasting diatom assemblages between these two interglacials provide a snapshot of varying water depth and, by inference, climate. Analysis of MIS7e samples suggests that lake water levels were low after a period when the lake was open (i.e., high lake levels with the presence of an outflow present), resulting in higher salinities and possibly less stable bottom waters, which switched between anoxic and oxic states more frequently. By contrast, the diatom assemblages during MIS5e are characteristic of fresh, relatively nutrient rich waters. This suggests that lake levels were high, that the lake was hydrologically open with an outlet, and that the bottom waters were anoxic for long periods of time. Furthermore, our palaeoconductivity estimates and modelling of the past lake volumes with respect to its salt content support the presence of an outflow. © 2017, The Author(s). 2018 English 09212728 10.1007/s10933-017-9973-z Journal of Paleolimnology 59 Springer Netherlands 119-133 Department of Life Sciences, Imperial College London, Silwood Park Campus, London, SL5 7PY, United Kingdom; Geological Institute, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland; Large Lakes Observatory, University of Minnesota, Duluth, MN, United States; Department of Water Resources and Drinking Water, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, Dübendorf, 8600, Switzerland; Institute of Geological Sciences, University of Bern, Baltzerstrasse 1+3, Bern, 3012, Switzerland; Environmental Change Research Centre, Department of Geography, UCL, London, United Kingdom 1 biostratigraphy; chemical environmental conditions; deposition; depositional environment; diatom; dissolution; fossil record; Holocene; interglacial; lacustrine deposit; lake ecosystem; lake level; marine isotope stage; paleohydrology; paleolimnology; project assessment; salinity; sedimentary sequence; water depth, Anatolia; Lake Van; Turkey, Bacillariophyta https://www.scopus.com/inward/record.uri?eid=2-s2.0-85020688154&doi=10.1007%2fs10933-017-9973-z&partnerID=40&md5=0060ec808c5bdc0584a03b4c0a078507 cited By 10 S.M. North M. Stockhecke Y. Tomonaga A.W. Mackay article Damcı201829 The Lake Van is the largest Lake in Turkey and the fourth largest soda lake in the World. High resolution (HR) seismic data acquired during 2012 reveals sub-lacustrine terraces, delta clinoforms, channel-networks, active faults and volcanic edifices. The seismic data were correlated with the cores recovered during the 2008 coring and 2010 ICDP PaleoVan drilling campaigns, using synthetic seismograms produced from the MSCL data of the age-modelled cores, thus allowing to date seismic reflector surfaces and to discuss the temporal evolution of the some of the morphological features and structures. Sub-lacustrine channel-network systems are well developed on the shelf areas connect with the river drainage systems on land and extend to water depths of more than 100 m. These drainage systems developed during the major low-stand periods of Lake Van, the last two of which occurred during 15 ka BP and the Younger Dryas with water levels at −200 m and −70 m, respectively. High lake levels similar to today during the early Holocene were followed by lake level oscillations with some low-stands during the Late Holocene. The low stands are characterized by terraces and berms located at 15 m below lake surface (mbls), 25 mbls, 35 mbls and 60 mbls, 70 mbls and 105 mbls. They were most likely related to the rapid climate change (RCC) events such as the 4.2 ka aridity event, Dark Age Cold Period, Medieval Warm Period and Little Ice. The volcanic features are located along the Southern Boundary Fault (SBF). A significant NW-SE trending active fault in the eastern shelf left-laterally offsets a channel by about 500 m and has a small reverse component in the HR seismic profiles. This fault is considered to be the source of Mw = 5.7 Edremit Earthquake of 9 November 2011. NW-SE trending normal faults with a right-lateral strike slip component north of the Northern Basin provides extension in the area. Normal faults are also dominant in the Erciş Strait. Using ages of reflector surfaces we estimate a vertical slip rate of 0.40 mm/yr to ∼0.5 mm/yr on the normal faults in the shelf areas over the last 2–3 ka. © 2017 Elsevier Ltd and INQUA 2018 English 10406182 10.1016/j.quaint.2017.12.047 Quaternary International 486 Elsevier Ltd 29-43 Istanbul Technical University, Eurasia Institute of Earth Sciences, Ayazağa Yerleşkesi, Istanbul, 34469, Turkey; Istanbul Technical University, EMCOL, Department of Geological Engineering, Faculty of Mining, Ayazağa Yerleşkesi, İstanbul, 34469, Turkey active fault; chronology; climate variation; correlation; geomorphology; Holocene; paleoclimate; seismic data; seismic reflection; seismogram; tectonic setting, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-85039904921&doi=10.1016%2fj.quaint.2017.12.047&partnerID=40&md5=c4fc13084b6cc009554927643d025602 cited By 2 E. Damcı M.N. Çağatay article Makaroğlu201844 Detailed magnetic analysis of the four sediment cores from Lake Van, Eastern Turkey dating back to 9.4 cal ka BP were carried out for discriminating and correlating tephras and laminated sediments in four different cores. Six tephra units (T0, T1, T2, T3, T4 and T5) with distinct magnetic properties were identified in the cores. The tephra units are characterized by ferrimagnetic material, with a grain size in the pseudo single domain (PSD) range. There is no significant correlation between magnetic susceptibility peaks of the different tephra units except for the tephra T1 and T2. On the contrary ARM profiles show significant correlations as remanent magnetization indicators. The tephra units T1 and T2, have a higher magnetic susceptibility and a higher intensity of remanent magnetization, and finer grain size than the other tephra units. The results suggest that there is a clear difference between the magnetic properties of the different tephra units and the lake sediments. Our findings show that also differential deposition of volcanic material including magnetic mineral occurs during the transport with distance from the volcanic source. © 2018 Elsevier Ltd and INQUA 2018 English 10406182 10.1016/j.quaint.2018.03.012 Quaternary International 486 Elsevier Ltd 44-56 Istanbul University, Faculty of Engineering, Department of Geophysical Engineering, Avcilar, Istanbul 34320, Turkey; Istanbul Technical University, Eastern Mediterranean Centre for Oceanography and Limnology EMCOL and Faculty of Mines, Department of Geological Engineering, Maslak, Istanbul 34469, Turkey; Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Section 5.2 – Paleoclimate and Landscape Evolution, Potsdam, 14473, Germany; University of Helsinki, Department of Physics, Division of Geophysics and Astronomy, Helsinki, FIN-00014, Finland geochemistry; Holocene; lacustrine deposit; magnetic mineral; magnetic susceptibility; remanent magnetization; sediment core; tephra, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-85044507473&doi=10.1016%2fj.quaint.2018.03.012&partnerID=40&md5=71af34ee8b14c83898756ba2fae473b7 cited By 5 Ö. Makaroğlu M.N. Çağatay N.R. Nowaczyk L.J. Pesonen N. Orbay article Schmincke2018 The Incekaya hyaloclastite cone (eastern Anatolia, Turkey), the focal point along a major eruptive fissure, was the main source of an unusually large explosive basaltic eruption. The ca. 80 ka-old eruption began onshore with scoria cones from a 5 km N-S fracture propagating toward Lake Van (surface area of 3755 km2). At the intersection with the fault-bounded lake basin, a ca. 400-m-high subaerial hyaloclastite edifice formed, which can be crudely subdivided into a main lower massive bulk of hydrothermally altered lithic-rich hyaloclastites (CL) topped unconformably by a &gt; 30-m-thick, well-bedded fallout tephra (CU). The CU tephras are correlated with (1) widespread onshore hyaloclastite fallout deposits mostly west-southwest of the cone and (2) a ca. 2-m-thick, ca 80-ka-old bedded hyaloclastite (V-60), part of a 220 m ICDP (International Continental Scientific Drilling Program) core, drilled in Lake Van, 27 km N of Incekaya. The hyaloclastite unit was seismically identified as being the most widespread and well-defined reflector throughout much of western Lake Van. A minimum volume of &gt; 9 km3 fallout hyaloclastite tephra is estimated when the area of the seismic reflector is extrapolated to the coast and 2 km inland. Seismic reflectors also suggest at least two (hyaloclastite?) intralake cones rising up to 388 m above the lake sediment surface 1.5 km NW off Incekaya cone and were possibly erupted along the same fracture. The total volume of hyaloclastites includes (a) subaerial Incekaya cone, (b) the inferred subaqueous continuation of the cone(s), (c) the bedded intralake and onshore deposits, and, tentatively, (d) a widespread (seismically defined) mass flow deposits directly beneath Incekaya reflector of roughly 20 km3 and may represent the deposits of explosively erupted basaltic magma. Sideromelane shards, the main clast type, are dominantly angular, and most show ≪ 50 vol.% vesicles. Less common tachylite clasts are poorly vesicular (&lt; 50 vol.%). Structural transitions and interlayering between tachylite and sideromelane are ubiquitous. Fluidal and pumiceous lapilli are present in the basal massive facies. Bulk rock and glass compositions indicate constant composition of the slightly evolved Al-rich basalt magma. Olivine (Fo78–82) and plagioclase (An70–80) microphenocrysts, many skeletal with growth features, and microlites make up &lt; 1 vol.% and suggest rapid magma ascent. The high explosive energy of the eruption is interpreted to be due to (1) high magma discharge rates and shearing in the eruptive jet and (2) magma-water interaction conditions. Approximate temporal coincidences with the Incekaya eruption include the following: (a) an abrupt cessation in the supply of evolved tephra from the adjacent Süphan Volcano to the lake sediments, which ended abruptly for ca. 60 ky, (b) an extreme fall in lake level by ca. 150 m, and (c) a drastic increase in pore water salinity (Na+ and Cl− (g/L)) and pH. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature. 2018 English 02588900 10.1007/s00445-018-1257-6 Bulletin of Volcanology 80 Springer Verlag GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, Kiel, 24148, Germany; Korea Institute of Geoscience and Mineral Resources (KIGAM), 124 Gwahak-ro, Yuseong-gu, Daejeon 34132, South Korea 12 fissure; hyaloclastite; phreatomagmatism; plinian eruption; pyroclastic deposit; volcanic eruption; volcanism, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-85056118270&doi=10.1007%2fs00445-018-1257-6&partnerID=40&md5=cafc8c93f618a9f921538beb98955f6d cited By 0 H.-U. Schmincke M. Sumita D. Cukur article Tomonaga2017 In closed-basin lakes, sediment porewater salinity can potentially be used as a conservative tracer to reconstruct past fluctuations in lake level. However, until now, porewater salinity profiles did not allow quantitative estimates of past lake-level changes because, in contrast to the oceans, significant salinity changes (e.g., local concentration minima and maxima) had never been observed in lacustrine sediments. Here we show that the salinity measured in the sediment pore water of Lake Van (Turkey) allows straightforward reconstruction of two major transgressions and a major regression that occurred during the last 250 ka. We observed strong changes in the vertical salinity profiles of the pore water of the uppermost 100 m of the sediments in Lake Van. As the salinity balance of Lake Van is almost at steady-state, these salinity changes indicate major lake-level changes in the past. In line with previous studies on lake terraces and with seismic and sedimentological surveys, we identify two major transgressions of up to +105 m with respect to the current lake level at about 135 ka BP and 248 ka BP starting at the onset of the two previous interglacials (MIS5e and MIS7), and a major regression of about-200 m at about 30 ka BP during the last ice age. © 2017 The Author(s). 2017 English 20452322 10.1038/s41598-017-00371-w Scientific Reports 7 Nature Publishing Group Eawag Swiss Federal Institute of Aquatic Science and Technology, Department of Water Resources and DrinkingWater, Überlandstrasse 133, Dübendorf, 8600, Switzerland; Atmosphere and Ocean Research Institute, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba, 277-8564, Japan; Institute of Geological Sciences, University of Bern, Baltzerstrasse 1+3, Bern, 3012, Switzerland; Geological Institute, Swiss Federal Institute of Technology (ETH), Zürich, 8092, Switzerland; Ruhr-University Bochum, Universitätstrasse 150, Bochum, 44801, Germany; Eawag Swiss Federal Institute of Aquatic Science and Technology, Department Surface Water Research and Management, Seestrasse 79, Kastanienbaum, 6047, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology (ETH), Zürich, 8092, Switzerland; Eawag Swiss Federal Institute of Aquatic Science and Technology, Department Surface Water Research and Management, Überlandstrasse 133, Dübendorf, 8600, Switzerland; Oeschger Centre for Climate Change Research, University of Bern, Falkenplatz 16, Bern, 3012, Switzerland; Institute of Geochemistry and Petrology, Swiss Federal Institute of Technology (ETH), Zurich, 8092, Switzerland 1 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85017145585&doi=10.1038%2fs41598-017-00371-w&partnerID=40&md5=8ba26f64512e89710a91e3356178d953 cited By 21 Y. Tomonaga M.S. Brennwald D.M. Livingstone O. Kwiecien M.-E. Randlett M. Stockhecke K. Unwin F.S. Anselmetti J. Beer G.H. Haug C.J. Schubert M. Sturm R. Kipfer article Cukur2017239 The structural evolution of Lake Van Basin, eastern Turkey, was reconstructed based on seismic reflection profiles through the sedimentary fill as well as from newly acquired multibeam echosounder data. The major sub-basins (Tatvan Basin and Northern Basin) of Lake Van, bound by NE-trending faults with normal components, formed during the past ~600 ka probably due to extensional tectonics resulting from lithospheric thinning and mantle upwelling related to the westward escape of Anatolia. Rapid extension and subsidence during early lake formation led to the opening of the two sub-basins. Two major, still active volcanoes (Nemrut and Süphan) grew close to the lake basins approximately synchronously, their explosive deposits making up >20 % of the drilled upper 220 m of the ca. 550-m-thick sedimentary fill. During basin development, extension and subsidence alternated with compressional periods, particularly between ~340 and 290 ka and sometime before ~14 ka, when normal fault movements reversed and gentle anticlines formed as a result of inversion. The ~14 ka event was accompanied by widespread uplift and erosion along the northeastern margin of the lake, and substantial erosion took place on the crests of the folds. A series of closely spaced eruptions of Süphan volcano occurred synchronously suggesting a causal relationship. Compression is still prevalent inside and around Lake Van as evidenced by recent faults offsetting the lake floor and by recent devastating earthquakes along their onshore continuations. New, high-resolution bathymetry data from Lake Van reveal the morphology of the Northern Ridge and provide strong evidence for ongoing transpression on a dextral strike-slip fault as documented by the occurrence of several pop-up structures along the ridge. © 2016, Springer-Verlag Berlin Heidelberg. 2017 English 14373254 10.1007/s00531-016-1312-5 International Journal of Earth Sciences 106 Springer Verlag 239-253 Petroleum and Marine Research Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), 124 Gwahang-no, Yuseong-gu, Daejeon, 305-350, South Korea; Institute of Geosciences, Kiel University, Otto-Hahn-Platz 1, Kiel, 24118, Germany; Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba, 277-8564, Japan; Department of Water Resources and Drinking Water, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, Duebendorf, 8600, Switzerland; GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, Kiel, 24148, Germany; Department of Geological Engineering, Van Yüzüncü Yıl University, Van, Turkey; Department of Geological Engineering, Istanbul Technical University, EMCOL, Maslak, Istanbul, 34469, Turkey; Department of Geophysical Engineering, Van Yüzüncü Yıl University, Van, Turkey 1 basin evolution; compression; extensional tectonics; mantle upwelling; seismic data; seismic reflection; spectral resolution; volcanism, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84960347031&doi=10.1007%2fs00531-016-1312-5&partnerID=40&md5=960a65711079ebc4c8376b869807bbc5 cited By 21 D. Cukur S. Krastel Y. Tomonaga H.-U. Schmincke M. Sumita A.F. Meydan M.N. Çağatay M. Toker S.-P. Kim G.-S. Kong S. Horozal article Toker2017165 This study analyzed multi-channel seismic reflection data from Lake Van, Eastern Anatolia, to provide key information on the structural elements, deformational patterns and overall tectonic structure of the Lake Van basin. The seismic data reveal three subbasins (the Tatvan, northern and Ahlat subbasins) separated by structural ridges (the northern and Ahlat ridges). The Tatvan basin is a tilted wedge-block in the west, it is a relatively undeformed and flat-lying deep basin, forming a typical example of strike-slip sedimentation. Seismic sections reveal that the deeper sedimentary sections of the Tatvan basin are locally folded, gently in the south and more intensely further north, suggesting a probable gravitational “wedge-block” instability, oblique to the northern margin. The northern subbasin, bounded by normal oblique faults, forms a basin-margin graben structure that is elongated in a northeast-southwest direction. The east-west trending Ahlat ridge forms a fault-wedged sedimentary ridge and appears to offset by reverse oblique faults forming as a push-up rhomb horst structure. The Ahlat subbasin is a fault-wedged trough fill that is elongated in the west-east direction and appears as a horst-foot graben formed by the normal oblique faults. The northeast-southwest directed northern ridge is a faulted crestal terrace of a sublacustrine basement block. Its step-like morphology, in response to the downfaulting of the Tatvan basin, as well as its backthrusted appearance, indicates the normal oblique nature of the bounding faults. The lacustrine shelf and slope show distinctive stratigraphic features; progradational deltas, submerged fluvial channels, distorted and collapsed beddings and soft sediment deformation structures, characterizing a highly unstable nature of shelf caused by strong oblique faulting and related earthquakes. The faulting caused uplift of the Çarpanak spur zone, together with the northeastern Erek delta, deformation of deltaic structures and subsequently exposing the shelf and slope areas. The exposed areas are evident in the angular unconformity surface of the Çarpanak basement block with the northeastern Erek delta and thinned sediments. The uplift resulted in the asymmetric depositional emplacement of the southeastern delta that is controlled by a series of ramp anticlines/low angle reverse faults. The Deveboynu subbasin and Varis spur zone form wide fault-controlled depressions with thick sediments that are elongated in the north-south direction. These subbasins appear as a small pull-apart boundary formed by normal oblique faults at the western end of the southeastern delta. © 2017 Elsevier Ltd 2017 English 1464343X 10.1016/j.jafrearsci.2017.01.002 Journal of African Earth Sciences 129 Elsevier Ltd 165-178 Yuzuncu Yıl University, Department of Geophysical Engineering, Zeve Campus, Van, 65080, Turkey; University of Oulu, Sodankylä Geophysical Observatory (SGO-Oulu unit), POB 3000, Oulu, 90014, Finland; Istanbul Technical University, Eurasia Institute of Earth Sciences, Ayazaga Campus, Maslak-Istanbul, Turkey; University of Bremen, Department of Geosciences, Bremen, Germany; Istanbul Technical University, Department of Geophysical Engineering, Ayazaga Campus, Maslak-Istanbul, Turkey; Korea Institute of Geoscience and Mineral Resources (KIGAM), Petroleum and Marine Research Division, Daejeon, 305-305, South Korea; Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, 27515, Germany deformation; graben; normal fault; reverse fault; sedimentation; seismic data; seismic reflection; strike-slip fault; tectonic structure; uplift; vertical seismic profile, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-85009080899&doi=10.1016%2fj.jafrearsci.2017.01.002&partnerID=40&md5=b36f1284d04d122429936e5355346d87 cited By 19 M. Toker A.M.C. Sengor F. Demirel Schluter E. Demirbag D. Cukur C. Imren PaleoVan-Working Group article Engelhardt2017144 Volcaniclastic fall deposits in ICDP drilling cores from Lake Van, Turkey, contain sodium-rich sanidine and calcium-rich anorthoclase, which both comprise a variety of textural zoning and inclusions. An age model records the lake's history and is based on climate-stratigraphic correlations, tephrostratigraphy, paleomagnetics, and earlier 40Ar/39Ar analyses (Stockhecke et al., 2014b). Results from total fusion and stepwise heating 40Ar/39Ar analyses presented in this study allow for the comparison of radiometric constraints from texturally diversified feldspar and the multi-proxy lacustrine age model and vice versa. This study has investigated several grain-size fractions of feldspar from 13 volcaniclastic units. The feldspars show textural features that are visible in cathodoluminescence (CL) or back-scattered electron (BSE) images and can be subdivided into three dominant zoning-types: (1) compositional zoning, (2) round pseudo-oscillatory zoning and (3) resorbed and patchy zoning (Ginibre et al., 2004). Round pseudo-oscillatory zoning records a sensitive alternation of Fe and Ca that also reflects resorption processes. This is only visible in CL images. Compositional zoning reflects anticorrelated anorthite and orthoclase contents and is visible in BSE. Eleven inverse isochron ages from total fusion and three from stepwise heating analyses fit the age model. Four experiments resulted in older inverse isochron ages that do not concur with the model within 2σ uncertainties and that deviate from 1 ka to 17 ka minimum. C- and R-type zoning are interpreted as representing growth in magma chamber cupolas, as wall mushes, or in narrow conduits. Persistent compositions of PO-type crystals and abundant surfaces recording dissolution features correspond to formation within a magma chamber. C-type zoning and R-type zoning have revealed an irregular incorporation of melt and fluid inclusions. These two types of zoning in feldspar are interpreted as preferentially contributing either heterogeneously distributed excess 40Ar or inherited 40Ar to the deviating 40Ar/39Ar ages that are discussed in this study. © 2017 Elsevier Ltd 2017 English 00167037 10.1016/j.gca.2017.07.039 Geochimica et Cosmochimica Acta 217 Elsevier Ltd 144-170 Institut für Erd- und Umweltwissenschaften, Universität Potsdam, Karl-Liebknecht-Str. 24-25, Potsdam, 14476, Germany; Large Lakes Observatory, University of Minnesota, 2205 E. 5th Street, Duluth, MN 55812-3024, United States argon-argon dating; feldspar; grain size; lacustrine deposit; radiocarbon dating; sediment core; volcaniclastic deposit, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-85028721559&doi=10.1016%2fj.gca.2017.07.039&partnerID=40&md5=62261f60f0c4fdaf5cc4d207996ab4a8 cited By 4 J.F. Engelhardt M. Sudo M. Stockhecke R. Oberhänsli article Kallmeyer201761 Drilling is an integral part of subsurface exploration. Because almost all drilling operations require the use of a drill fluid, contamination by infiltration of drill fluid into the recovered core material cannot be avoided. Because it is impossible to maintain sterile conditions during drilling the drill fluid will contain surface microbes and other contaminants. As contamination cannot be avoided, it has to be tracked to identify those parts of the drill core that were not infiltrated by the drill fluid. This is done by the addition of tracer compounds. A great variety of tracers is available, and the choice depends on many factors. This review will first explain the basic principles of drilling before presenting the most common tracers and discussing their strengths and weaknesses. The final part of this review presents a number of key questions that have to be addressed in order to find the right tracer for a particular drilling operation. © 2017 Elsevier Inc. 2017 English 00652164 10.1016/bs.aambs.2016.09.003 Advances in Applied Microbiology 98 Academic Press Inc. 61-91 GFZ German Research Centre for Geosciences, Potsdam, Germany fluorescent dye; fluorocarbon; microsphere; tracer, Article; drill; ecological procedures; extended core barrel; gravity; hydraulic piston coring; microbial contamination; nonhuman; rotary drilling; tube; wireline coring; bacterium; chemistry; devices; ecosystem; genetics; growth, development and aging; human; isolation and purification; microbiology; mining; procedures; sediment, Bacteria; Ecosystem; Extraction and Processing Industry; Geologic Sediments; Humans https://www.scopus.com/inward/record.uri?eid=2-s2.0-85005991804&doi=10.1016%2fbs.aambs.2016.09.003&partnerID=40&md5=cf94c86c1e4af01a4407c6a5b4b9b682 cited By 10 J. Kallmeyer article Randlett2017571 Lipid biomarkers were analyzed in Lake Van sediments covering the last 600 ka, with a focus on the period between 110 and 10 ka, when a broad maximum in pore water salinity as a relict from the past suggests dry conditions. The occurrence and distribution of biomarkers indicative for terrestrial plants (long-chain n-alkane C29), haptophyte algae (methyl alkenones C37) and halophilic archaea (archaeol) all point toward a dry climate in Lake Van region during this time interval. The hydrogen isotopic composition of C29 n-alkanes (δDC29) and C37 alkenones (δDC37) is enriched between MIS 4 and MIS 2, which is interpreted as a decrease in the regional ratio of precipitation to evaporation. Similarly, the low abundance of the acyclic glycerol dialkyl glycerol tetraether GDGT-0 relative to archaeol, quantified by the Archaeol and Caldarchaeol Ecometric (ACE) is assumed to reflect the presence of halophilic euryarchaeota adapted to high salinity water. The climate around Lake Van appears in phase with the Yammouneh basin 800 km southwest and Lake Urmia 250 km southeast of Lake Van over the last two glacial periods. The results highlight the potential of combining ACE, δDC29, and δDC37 for reconstructing salinity changes and regional precipitation to evaporation ratio from lake sediments. © 2017. American Geophysical Union. All Rights Reserved. 2017 English 15252027 10.1002/2016GC006621 Geochemistry, Geophysics, Geosystems 18 Blackwell Publishing Ltd 571-583 Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Surface Waters – Research and Management, Kastanienbaum, Switzerland; ETH Zurich, Institute of Biogeochemistry and Pollutant Dynamics, Zurich, Switzerland; Chair in Petroleum Geology, Montanuniversität, Leoben, Austria; NIOZ Royal Netherlands Institute for Sea Research and Utrecht University, Department of Marine Microbiology and Biogeochemistry, 't Horntje (Texel), Netherlands; Department of Earth Sciences, Utrecht University, Utrecht, Netherlands; Steinmann Institute of Geology, Mineralogy and Palaeontology, University of Bonn, Bonn, Germany; Ruhr-Universität Bochum, Institut für Sediment- und Isotopengeologie, Bochum, Germany; Eawag, Department of Surface Water - Research and Management, Dübendorf, Switzerland; Large Lakes Observatory, University of Minnesota Duluth, Duluth, MN, United States 2 Evaporation; Glycerol; Isotopes; Lakes; Paraffins; Sediments, ACE index; Halophilic archaea; Hydrogen isotope; Hydrogen isotopic composition; Lake vans; Long chain n-alkanes; Occurrence and distribution; Pore water salinities, Biomarkers, biomarker; hydrogen isotope; isotopic composition; lacustrine deposit; lipid; paleoclimate; porewater; salinity, Anatolia; Lake Van; Turkey, algae; Euryarchaeota https://www.scopus.com/inward/record.uri?eid=2-s2.0-85013301833&doi=10.1002%2f2016GC006621&partnerID=40&md5=8082cd340625cc67a378bbc9c8131c21 cited By 19 M.-E. Randlett A. Bechtel M.T.J. Meer F. Peterse T. Litt N. Pickarski O. Kwiecien M. Stockhecke B. Wehrli C.J. Schubert article Pickarski2017689 A new detailed pollen and oxygen isotope record of the penultimate interglacial-glacial cycle, corresponding to the marine isotope stage (MIS) 7-6, has been generated from the Ahlat Ridge (AR) sediment core at Lake Van, Turkey. The presented Lake Van pollen record (ca. 250.2-128.8 ka) displays the highest temporal resolution in this region with a mean sampling interval of ĝ1/4 540 years. The integration of all available proxies shows three temperate intervals of high effective soil moisture availability. This is evidenced by the predominance of steppe-forested landscapes (oak steppe-forest) similar to the present interglacial vegetation in this sensitive semiarid region between the Black Sea, the Caspian Sea, and the Mediterranean Sea. The wettest and warmest stage, as indicated by highest temperate tree percentages, can be broadly correlated with MIS 7c, while the amplitude of the tree population maximum during the oldest penultimate interglacial (MIS 7e) appears to be reduced due to warm but drier climatic conditions. The detailed comparison of the penultimate interglacial complex (MIS 7) to the last interglacial (Eemian, MIS 5e) and the current interglacial (Holocene, MIS 1) provides a vivid illustration of possible differences in the successive climatic cycles. Intervening periods of treeless vegetation can be correlated with MIS 7d and 7a, in which open landscapes favor local erosion and detrital sedimentation. The predominance of steppe elements (e.g., Artemisia, Chenopodiaceae) during MIS 7d indicates very dry and cold climatic conditions. In contrast, the occurrence of higher temperate tree percentages (mainly deciduous Quercus) throughout MIS 7b points to relatively humid and mild conditions, which is in agreement with other pollen sequences in southern Europe. Despite the general dominance of dry and cold desert-steppe vegetation during the penultimate glacial (broadly equivalent to MIS 6), this period can be divided into two parts: an early stage (ca. 193-157 ka) with higher oscillations in tree percentages and a later stage (ca. 157-131 ka) with lower tree percentages and subdued oscillations. This subdivision of the penultimate glacial is also seen in other pollen records from southern Europe (e.g., MD01-2444 and I-284; Margari et al., 2010; Roucoux et al., 2011). The occurring vegetation pattern is analogous to the division of MIS 3 and MIS 2 during the last glacial in the same sediment sequence. Furthermore, we are able to identify the MIS 6e event (ca. 179-159 ka) as described in marine pollen records, which reveals clear climate variability due to rapid alternation in the vegetation cover. In comparison with long European pollen archives, speleothem isotope records from the Near East, and global climate parameters (e.g., insolation, atmospheric CO2 content), the new high-resolution Lake Van record presents an improved insight into regional vegetation dynamics and climate variability in the eastern Mediterranean region. © Author(s) 2017. 2017 English 18149324 10.5194/cp-13-689-2017 Climate of the Past 13 Copernicus GmbH 689-710 University of Bonn, Steinmann Institute for Geology, Mineralogy and Paleontology, Bonn, Germany 6 climate variation; core analysis; forest-steppe; glacial-interglacial cycle; marine isotope stage; oxygen isotope; paleoecology; paleoenvironment; palynology; proxy climate record; soil moisture; vegetation history, Black Sea; Caspian Sea; Lake Van; Mediterranean Sea; Turkey, Amaranthaceae; Artemisia; Quercus https://www.scopus.com/inward/record.uri?eid=2-s2.0-85020498493&doi=10.5194%2fcp-13-689-2017&partnerID=40&md5=a2b328bc8258274588ba34f297fa16c7 cited By 26 N. Pickarski T. Litt article Adhikari2016 Subsurface microbial communities undertake many terminal electron-accepting processes, often simultaneously. Using a tritium-based assay, we measured the potential hydrogen oxidation catalyzed by hydrogenase enzymes in several subsurface sedimentary environments (Lake Van, Barents Sea, Equatorial Pacific, and Gulf of Mexico) with different predominant electron-acceptors. Hydrogenases constitute a diverse family of enzymes expressed by microorganisms that utilize molecular hydrogen as a metabolic substrate, product, or intermediate. The assay reveals the potential for utilizing molecular hydrogen and allows qualitative detection of microbial activity irrespective of the predominant electron-accepting process. Because the method only requires samples frozen immediately after recovery, the assay can be used for identifying microbial activity in subsurface ecosystems without the need to preserve live material. We measured potential hydrogen oxidation rates in all samples from multiple depths at several sites that collectively span a wide range of environmental conditions and biogeochemical zones. Potential activity normalized to total cell abundance ranges over five orders of magnitude and varies, dependent upon the predominant terminal electron acceptor. Lowest per-cell potential rates characterize the zone of nitrate reduction and highest per-cell potential rates occur in the methanogenic zone. Possible reasons for this relationship to predominant electron acceptor include (i) increasing importance of fermentation in successively deeper biogeochemical zones and (ii) adaptation of H2ases to successively higher concentrations of H2 in successively deeper zones. © 2016 Adhikari, Glombitza, Nickel, Anderson, Dunlea, Spivack, Murray, D'Hondt and Kallmeyer. 2016 English 1664302X 10.3389/fmicb.2016.00008 Frontiers in Microbiology 7 Frontiers Media S.A. MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany; Geomicrobiology Group, Institute of Earth and Environmental Science, University of Potsdam, Potsdam, Germany; Center for Geomicrobiology, Department of Bioscience, Aarhus University, Aarhus C, Denmark; Helmholtz-Centre Potsdam - GFZ German Research Centre for Geosciences, Potsdam, Germany; Department of Earth and Environment, Boston University, Boston, MA, United States; Graduate School of Oceanography, University of Rhode Island, Kingston, RI, United States JAN hydrogen; hydrogenase; iron; manganese; sulfate, Article; ecosystem; enzyme assay; Gulf of Mexico; metabolic activity assay; microbial activity; microbial community; nonhuman; Pacific Ocean; radioactivity; sediment; temperature; Turkey (republic); water analysis https://www.scopus.com/inward/record.uri?eid=2-s2.0-84957954218&doi=10.3389%2ffmicb.2016.00008&partnerID=40&md5=4e2684f27d2246dc4f721d005bef0e1a cited By 14 R.R. Adhikari C. Glombitza J.C. Nickel C.H. Anderson A.G. Dunlea A.J. Spivack R.W. Murray S. D'Hondt J. Kallmeyer article Stockhecke201677 Millennial to orbital-scale rainfall changes in the Mediterranean region and corresponding variations in vegetation patterns were the result of large-scale atmospheric reorganizations. In spite of recent efforts to reconstruct this variability using a range of proxy archives, the underlying physical mechanisms have remained elusive. Through the analysis of a new high-resolution sedimentary section from Lake Van (Turkey) along with climate modeling experiments, we identify massive droughts in the Eastern Mediterranean for the past four glacial cycles, which have a pervasive link with known intervals of enhanced North Atlantic glacial iceberg calving, weaker Atlantic Meridional Overturning Circulation and Dansgaard-Oeschger cold conditions. On orbital timescales, the topographic effect of large Northern Hemisphere ice sheets and periods with minimum insolation seasonality further exacerbated drought intensities by suppressing both summer and winter precipitation. © 2015 Elsevier Ltd. 2016 English 02773791 10.1016/j.quascirev.2015.12.016 Quaternary Science Reviews 133 Elsevier Ltd 77-95 Large Lakes Observatory, University of Minnesota Duluth, 10 University Drive 206 RLB, Duluth, MN 55812-2496, United States; Geological Institute, Swiss Federal Institute of Technology (ETH), Sonneggstrasse 5, Zürich, 8092, Switzerland; Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Surface Waters Research and Management, Überlandstrasse 133, Dübendorf, 8600, Switzerland; IPRC, and Department of Oceanography, SOEST, University of Hawaii, 1680 East-West Road, Honolulu, HI 96822, United States; Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Water Resources and Drinking Water, Überlandstrasse 133, Dübendorf, 8600, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology (ETH), Universitätstrasse 16, Zürich, 8092, Switzerland; Institute of Geochemistry and Petrology, Swiss Federal Institute of Technology (ETH), Clausiusstrasse 25, Zürich, 8092, Switzerland; Ruhr-University Bochum, Universitätsstrasse 150, Bochum, 44801, Germany; CCRC, University of New South Wales, Matthews Building Level 4, Sydney, NSW 2052, Australia; ARC Centre of Excellence for Climate System Science, Australia; Steinmann Institute of Geology, Mineralogy and Paleontology, Bonn University, Nussallee 8, Bonn, 53115, Germany; Institute of Geological Sciences, University of Bern, Baltzerstrasse 1+3, Bern, 3012, Switzerland; Oeschger Centre for Climate Change Research (OCCR), University of Bern, Switzerland Glacial geology; Lakes; Sea ice, Atlantic meridional overturning circulations; Atmospheric reorganization; Dansgaard-Oeschger variability; Eastern Mediterranean; ICDP PALEOVAN; Insolation seasonality; Lake vans; Milankovitch cycle, Drought, climate change; climate modeling; Dansgaard-Oeschger cycle; drought; ice sheet; iceberg calving; Last Glacial-Interglacial; Mediterranean environment; Northern Hemisphere; paleoclimate; precipitation (climatology); seasonality; sediment analysis, Atlantic Ocean; Atlantic Ocean (North); Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84952838092&doi=10.1016%2fj.quascirev.2015.12.016&partnerID=40&md5=2da3181f03ab58af613e18a2aba2313c cited By 68 M. Stockhecke A. Timmermann R. Kipfer G.H. Haug O. Kwiecien T. Friedrich L. Menviel T. Litt N. Pickarski F.S. Anselmetti article Pickarski2015145 A high-resolution multi-proxy record from Lake Van, eastern Anatolia, derived from a lacustrine sequence cored at the 357m deep Ahlat Ridge (AR), allows a comprehensive view of paleoclimate and environmental history in the continental Near East during the last interglacial (LI). We combined paleovegetation (pollen), stable oxygen isotope (δ18Obulk) and XRF data from the same sedimentary sequence, showing distinct variations during the period from 135 to 110ka ago leading into and out of full interglacial conditions. The last interglacial plateau, as defined by the presence of thermophilous steppe-forest communities, lasted ca. 13.5ka, from ~129.1-115.6ka BP.The detailed palynological sequence at Lake Van documents a vegetation succession with several climatic phases: (I) the Pistacia zone (ca. 131.2-129.1. ka BP) indicates summer dryness and mild winter conditions during the initial warming, (II) the Quercus-. Ulmus zone (ca. 129.1-127.2. ka BP) occurred during warm and humid climate conditions with enhanced evaporation, (III) the Carpinus zone (ca. 127.2-124.1. ka BP) suggest increasingly cooler and wetter conditions, and (IV) the expansion of Pinus at ~. 124.1. ka BP marks the onset of a colder/drier environment that extended into the interval of global ice growth. Pollen data suggest migration of thermophilous trees from refugial areas at the beginning of the last interglacial. Analogous to the current interglacial, the migration documents a time lag between the onset of climatic amelioration and the establishment of an oak steppe-forest, spanning 2.1. ka. Hence, the major difference between the last interglacial compared to the current interglacial (Holocene) is the abundance of Pinus as well as the decrease of deciduous broad-leaved trees, indicating higher continentality during the last interglacial. Finally, our results demonstrate intra-interglacial variability in the low mid-latitudes and suggest a close connection with the high-frequency climate variability recorded in Greenland ice cores. © 2015 Elsevier B.V. 2015 English 00310182 10.1016/j.palaeo.2015.06.015 Palaeogeography, Palaeoclimatology, Palaeoecology 435 Elsevier 145-158 University of Bonn, Steinmann Institute for Geology, Mineralogy and Paleontology, Nussallee 8, Bonn, D-53115, Germany; Ruhr-University Bochum, Institute for Geology, Mineralogy and Geophysics, Universitätsstrasse 150, Bochum, D-44801, Germany; Institut Méditerranéen de Biodiversite et d'Ecologie marine et continentale (IMBE), UMR CNRS 7263/IRD 237, Aix-Marseille Université, Technopôle de l'Environnement Arbois-Méditerranée, BP 80, Aix-en-Provence cedex 04, F-13545, France abundance; climate conditions; climate variation; community structure; coniferous tree; data set; deciduous tree; environmental change; environmental history; lacustrine deposit; Last Interglacial; oxygen isotope; paleoecology; palynology; pollen; proxy climate record; resolution; stable isotope; steppe; succession; temperature effect; vegetation structure; X-ray fluorescence, Anatolia; Arctic; Greenland; Greenland Ice Sheet; Lake Van; Turkey, Carpinus; Pistacia; Quercus; Ulmus https://www.scopus.com/inward/record.uri?eid=2-s2.0-84934914233&doi=10.1016%2fj.palaeo.2015.06.015&partnerID=40&md5=be68b8f603b0f7dfc24fe52911a4a0c2 cited By 39 N. Pickarski O. Kwiecien M. Djamali T. Litt article Ariztegui20151655 Recently, the discovery of active microbial life in deep-sea sediments has triggered a rapid development of the field known as the “deep biosphere.” Geomicrobiological investigations in lacustrine basins have also shown a substantial microbial impact on lake sediments similar to that described for the marine record. Although only 30 % of the lake sites drilled by the International Continental Drilling Program (ICDP) have included microbial investigations, these lakes cover a relatively wide range of salinities (from 0.15 to 33.8 %), pH (from 6.0 to 9.8) and environmental conditions (from very arid to humid subtropical conditions). Here, we analyze results of very recent ICDP lake sites including subsurface biosphere research from southern Patagonia (Laguna Potrok Aike) to the Levantine area (Dead Sea) as well as the East Anatolian high plateau (Lake Van) and Macedonia (Lake Ohrid). These various settings allow the examination of the impact of contrasting environments on microbial activity and their subsequent role during early diagenesis. Furthermore, they permit the identification of biosignatures of former microbial activity recorded in the sediments as well as investigating the impact of microbes in biogeochemical cycles. One of the general outcomes of these preliminary investigations is data to support the hypothesis that microbes react to climatically driven environmental changes that have a direct impact on their subsurface distribution and diversity. This is clear at conspicuous levels associated with well-known climatic periods such as the Medieval Climatic Anomaly or the Little Ice Age. Although more research is needed, this relationship between prevailing microbial assemblages and different climatic settings appears to dominate the lacustrine sites studied until to date. © 2015, The Author(s). 2015 English 14373254 10.1007/s00531-015-1148-4 International Journal of Earth Sciences 104 Springer Verlag 1655-1665 Department of Earth Sciences, University of Geneva, rue des Maraichers 13, Geneva, 1205, Switzerland; Section 4.5 Geomicrobiology, Helmholtz Centre Potsdam, GFZ German Research for Geosciences, Potsdam, 14473, Germany 6 biosphere; deep-sea sediment; diagenesis; drilling; environmental change; genomics; geological record; geomicrobiology; lacustrine deposit; microbial activity; paleoclimate; sedimentary basin, Argentina; Dead Sea; Laguna Potrok Aike; Lake Ohrid; Lake Van; Levantine Sea; Mediterranean Sea; Patagonia; Santa Cruz [Argentina]; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84940958158&doi=10.1007%2fs00531-015-1148-4&partnerID=40&md5=0af1c04e97299773cc0ebbf26995db8d cited By 18 D. Ariztegui C. Thomas A. Vuillemin article Macdonald20151 Nemrut volcano, adjacent to Lake Van (Turkey), is one of the most important peralkaline silicic centres in the world, where magmatism for ~570,000 years has been dominated by peralkaline trachytes and rhyolites. Using onshore and Lake Van drill site tephra samples, we document the phenocryst and glass matrix compositions, confirming a complete spectrum from very rare mafic to dominantly silicic magmas. Magma mixing has been common and, along with the multi-lineage nature of the magmas, indicates that Nemrut has been a very open system where, nevertheless, compositionally zoned caps developed during periods of relative eruptive quiescence. Geothermometry suggests that the intermediate-silicic magmas evolved in an upper crustal magma reservoir at temperatures between 1100 and 750 °C, at fO2 close to the FMQ buffer. The silicic magmas either were halogen poor or exsolved a halogen-rich phase prior to or during eruption. An unusual Pb-rich phase, with up to 98.78 wt% PbO, is interpreted as having exsolved from the intermediate-rhyolitic magmas. © 2015, The Author(s). 2015 English 00107999 10.1007/s00410-015-1127-6 Contributions to Mineralogy and Petrology 169 Springer Verlag 1-22 IGMP Faculty of Geology, University of Warsaw, Żwirki i Wigury 93, Warsaw, 02-089, Poland; Environment Centre, Lancaster University, Lancaster, LA1 4YQ, United Kingdom; Geomar Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1, Kiel, 24148, Germany; Department of Geography and Geology, Eastern Kentucky University, Richmond, KY 40475, United States 4 felsic rock; geothermometry; glass; magmatism; peralkaline rock; phenocryst; rhyolite; tephra; trachyte, Bitlis; Lake Van; Nemrut; Turkey, Trachytes https://www.scopus.com/inward/record.uri?eid=2-s2.0-84925719387&doi=10.1007%2fs00410-015-1127-6&partnerID=40&md5=48df4b3690f2f4556618e4ca01bcdb33 cited By 18 R. Macdonald M. Sumita H.-U. Schmincke B. Bagiński J.C. White S.S. Ilnicki article Kallmeyer20151667 The ICDP “PaleoVan” drilling campaign at Lake Van, Turkey, provided a long (>100 m) record of lacustrine subsurface sedimentary microbial cell abundance. After the ICDP campaign at Potrok Aike, Argentina, this is only the second time deep lacustrine cell counts have been documented. Two sites were cored and revealed a strikingly similar cell distribution despite differences in organic matter content and microbial activity. Although shifted towards higher values, cell counts from Lake Potrok Aike, Argentina, reveal very similar distribution patterns with depth. The lacustrine cell count data are significantly different from published marine records; the most probable cause is differences in sedimentary organic matter composition with marine sediments containing a higher fraction of labile organic matter. Previous studies showed that microbial activity and abundance increase centimetres to metres around geologic interfaces. The finely laminated Lake Van sediment allowed studying this phenomenon on the microscale. We sampled at the scale of individual laminae, and in some depth intervals, we found large differences in microbial abundance between the different laminae. This small-scale heterogeneity is normally overlooked due to much larger sampling intervals that integrate over several centimetres. However, not all laminated intervals exhibit such large differences in microbial abundance, and some non-laminated horizons show large variability on the millimetre scale as well. The reasons for such contrasting observations remain elusive, but indicate that heterogeneity of microbial abundance in subsurface sediments has not been taken into account sufficiently. These findings have implications not just for microbiological studies but for geochemistry as well, as the large differences in microbial abundance clearly show that there are distinct microhabitats that deviate considerably from the surrounding layers. © 2015, The Author(s). 2015 English 14373254 10.1007/s00531-015-1219-6 International Journal of Earth Sciences 104 Springer Verlag 1667-1677 GFZ German Research Centre for Geosciences, Telegrafenberg, Potsdam, 14473, Germany; Earth and Environmental Sciences, University of Potsdam, Karl-Liebknecht Straße, Potsdam, 14476, Germany; Center for Geomicrobiology, Aarhus University, Ny Munkegade 114, Århus C, 8000, Denmark 6 biosphere; lacustrine deposit; microbial activity; microbial community; microbial ecology; relative abundance, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84940963557&doi=10.1007%2fs00531-015-1219-6&partnerID=40&md5=a75517f084f8dfe188e7cf64a1526c52 cited By 9 J. Kallmeyer S. Grewe C. Glombitza J.A. Kitte article Cukur2015329 In Lake Van of eastern Turkey, the fourth largest soda lake in the world, high-resolution subbottom profiles and bathymetric data acquired in 2004 and 2012 revealed several hundreds of topographic mounds in shallow waters (<130 m) off the historical town of Adilcevaz in the northern lake sector. These structures are characterized by strong top reflections of transparent internal character, and are 10–300 m wide and 0.5–20 m high. Consistent with previous work, they are interpreted as carbonate mounds formed by precipitation from CO2-rich groundwater discharge into the highly alkaline lake. Their age remains to be determined but their alignment along faults suggests tectonic control on their growth. Several sublacustrine channel networks were observed on the eastern shelf of the lake, which connects with onshore rivers. The channels are up to 500 m wide and 20 m deep, and plausibly were formed by fluvial processes during the major lake level drop reported to have occurred by 14 ka in earlier publications. Erosion is common on the channel walls flanked by levees. The channels are presently inactive or abandoned. At a water depth of 100 m, they all merge into a single larger channel; this channel has a sinuous course initially trending southwestward and then northwestward at a water depth of 130 m. Numerous closely spaced small channels (~10–200 m wide, 1–10 m deep) are also seen on the eastern lacustrine shelf, interpreted as denditric and parallel channel systems formed during lake level fall terminating at ~14 ka. Bathymetric data provide evidence of numerous sublacustrine canyons on the western slope of the lake’s northern basin, most likely remnants of relict rivers formed during this lowstand. © 2015, Springer-Verlag Berlin Heidelberg. 2015 English 02760460 10.1007/s00367-015-0410-x Geo-Marine Letters 35 Springer Verlag 329-340 Petroleum and Marine Research Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon, 305-350, South Korea; Institute of Geosciences, Kiel University, Otto-Hahn-Platz 1, Kiel, 24118, Germany; EMCOL and Department of Geological Engineering, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey; Department of Geological Engineering, Van Yüzüncü Yıl University, Van, 65080, Turkey 5 Bathymetry; Channel flow; Groundwater; Hydrographic surveys, Bathymetric data; Carbonate mounds; Chirp sub bottoms; Ground water discharge; Multibeam echo sounder; Parallel channel; Sub-bottom profiles; Tectonic control, Lakes, carbonate platform; fluvial process; lacustrine environment; levee; multibeam sonar; profiler; shallow water, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84941174888&doi=10.1007%2fs00367-015-0410-x&partnerID=40&md5=71a56fda93fcf871ac1c7f2fe75981c5 cited By 18 D. Cukur S. Krastel M.N. Çağatay E. Damcı A.F. Meydan S.-P. Kim article Baumgarten20151639 A deep drilling campaign was performed at Lake Van (Turkey) to enhance the understanding of the paleoenvironmental conditions of the Middle East. Cores were collected, and the sediments are mainly composed of clayey silts and tephra deposits. Spectral gamma ray data were acquired (0–210 m below lake floor), and the uranium data were used for cyclostratigraphic studies to estimate the sedimentation rates and the time of deposition. Detection and analysis of climate cycles require continuous sedimentation and cannot be applied to these sediments which include numerous tephra layers. Therefore, these layers were removed, and a synthetic log was created (cumulative thickness of the tephra ≈50 m; remaining lacustrine sediments ≈160 m). High amplitudes were detected and correlated to Milanković cycles. Their evolution was analyzed using the sliding window technique. The sedimentation rates varied from 22 to 33 cm/ka in the upper section. The sediments between the lake floor and a depth of 210 m were deposited over a period of 587 ka. Our results agree with core interpretations (e.g., correlation of total organic carbon with marine isotope stages) which suggest a time span of deposition of 600 ka. High-frequency cycles were detected and correlated with interstadials from the North Greenland δ18O record for the past 75 ka. The two datasets agreed closely. We conclude that climate signals, even on sub-Milanković scale, are imprinted in uranium of these sediments, and cyclostratigraphic methods are applicable if event layers are subtracted from the sediment record. © 2014, The Author(s). 2015 English 14373254 10.1007/s00531-014-1082-x International Journal of Earth Sciences 104 Springer Verlag 1639-1654 Leibniz Institute for Applied Geophysics (LIAG), Stilleweg 2, Hannover, 30655, Germany 6 cyclostratigraphy; lacustrine deposit; logging (geophysics); Milankovitch cycle; paleoclimate; paleoenvironment; Quaternary; sediment core; sedimentation rate; tephra; uranium, Arctic; Greenland; Lake Van; Middle East; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84940957014&doi=10.1007%2fs00531-014-1082-x&partnerID=40&md5=a3a685bbd079c0b97203db27c6d4872a cited By 12 H. Baumgarten T. Wonik article Pickarski20151491 Detailed analyses of the Lake Van pollen, Ca / K ratio, and stable oxygen isotope record allow the identification of millennial-scale vegetation and environmental changes in eastern Anatolia throughout the last glacial (∼ 111.5-11.7 ka BP). The climate of the last glacial was cold and dry, indicated by low arboreal pollen (AP) levels. The driest and coldest period corresponds to Marine Isotope Stage (MIS) 2 (∼ 28-14.5 ka BP), which was dominated by highest values of xerophytic steppe vegetation. <br><br> Our high-resolution multi-proxy record shows rapid expansions and contractions of tree populations that reflect variability in temperature and moisture availability. These rapid vegetation and environmental changes can be related to the stadial-interstadial pattern of Dansgaard-Oeschger (DO) events as recorded in the Greenland ice cores. Periods of reduced moisture availability were characterized by enhanced occurrence of xerophytic species and high terrigenous input from the Lake Van catchment area. Furthermore, the comparison with the marine realm reveals that the complex atmosphere-ocean interaction can be explained by the strength and position of the westerlies, which are responsible for the supply of humidity in eastern Anatolia. Influenced by the diverse topography of the Lake Van catchment, more pronounced DO interstadials (e.g., DO 19, 17-16, 14, 12 and 8) show the strongest expansion of temperate species within the last glacial. However, Heinrich events (HE), characterized by highest concentrations of ice-rafted debris (IRD) in marine sediments, cannot be separated from other DO stadials based on the vegetation composition in eastern Anatolia. In addition, this work is a first attempt to establish a continuous microscopic charcoal record for the last glacial in the Near East. It documents an immediate response to millennial-scale climate and environmental variability and enables us to shed light on the history of fire activity during the last glacial. © Author(s) 2015. 2015 English 18149324 10.5194/cp-11-1491-2015 Climate of the Past 11 Copernicus GmbH 1491-1505 University of Bonn, Steinmann Institute for Geology, Mineralogy, and Paleontology, Bonn, Germany; Ruhr-University Bochum, Sediment and Isotope Geology, Bochum, Germany; Tel Aviv University, Institute of Archaeology, Tel Aviv, Israel 11 carbon isotope; catchment; charcoal; climate variation; concentration (composition); Dansgaard-Oeschger cycle; GRIP; humidity; marine sediment; moisture; proxy climate record; stable isotope, Anatolia; Arctic; Greenland; Greenland Ice Sheet; Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84946546917&doi=10.5194%2fcp-11-1491-2015&partnerID=40&md5=74153686cc6d8ed336f638b857b576d9 cited By 41 N. Pickarski O. Kwiecien D. Langgut T. Litt article Cukur2014201 Sediments of Lake Van, Turkey, preserve one of the most complete records of continental climate change in the Near East since the Middle Pleistocene. We used seismic reflection profiles to infer past changes in lake level and discuss potential causes related to changes in climate, volcanism, and regional tectonics since the formation of the lake ca. 600 ka ago. Lake Van’s water level ranged by as much as 600 m during the past ~600 ka. Five major lowstands occurred, at ~600, ~365–340, ~290–230, ~150–130 and ~30–14 ka. During Stage A, between about 600 and 230 ka, lake level changed dramatically, by hundreds of meters, but phases of low and high stands were separated by long time intervals. Changes in the lake level were more frequent during the past ~230 ka, but less dramatic, on the order of a few tens of meters. We identified period B1 as a time of stepwise transgressions between ~230 and 150 ka, followed by a short regression between ca. 150 and 130 ka. Lake level rose stepwise during period B2, until ~30 ka. During the past ~30 ka, a regression and a final transgression occurred, each lasting about 15 ka. The major lowstand periods in Lake Van occurred during glacial periods, suggesting climatic control on water level changes (i.e. greatly reduced precipitation led to lower lake levels). Although climate forcing was the dominant cause for dramatic water level changes in Lake Van, volcanic and tectonic forcing factors may have contributed as well. For instance, the number of distinct tephra layers, some several meters thick, increases dramatically in the uppermost ~100 m of the sediment record (i.e. the past ~230 ka), an interval that coincides largely with low-magnitude lake level fluctuations. Tectonic activity, highlighted by extensional and/or compressional faults across the basin margins, probably also affected the lake level of Lake Van in the past. © 2014, Springer Science+Business Media Dordrecht. 2014 English 09212728 10.1007/s10933-014-9788-0 Journal of Paleolimnology 52 Kluwer Academic Publishers 201-214 GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, Kiel, 24148, Germany; Institute of Geosciences, Christian-Albrechts-Universität zu Kiel, Otto-Hahn-Platz 1, Kiel, 24118, Germany; Department of Water Resources and Drinking Water, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, Dübendorf, 8600, Switzerland; Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwa-noha, Kashiwa-shi, Chiba 277-8564, Japan; EMCOL and Department of Geological Engineering, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey 3 https://www.scopus.com/inward/record.uri?eid=2-s2.0-84939882522&doi=10.1007%2fs10933-014-9788-0&partnerID=40&md5=2d8aaa3104e927a925417007214154c3 cited By 32 D. Cukur S. Krastel H.U. Schmincke M. Sumita Y. Tomonaga M. Namık Çağatay article Cukur201463 More than 1500km of multi-channel seismic reflection profiles combined with ICDP (International Continental Scientific Drilling Program) drilling data, provide important insights into the stratigraphic evolution of Lake Van, eastern Turkey. Three major basins (Tatvan, Northern and the Deveboynu basins) comprise the main lake basin and are separated by morphological highs (Ahlat ridge and Northern ridge). Moreover, NE-SW faults, parallel to the general tectonic lineament of the area, dominate the entire basin and are in charge of creating graben and half-graben structures. Well-developed prograding deltaic sequences on top of the basement were recognized by seismic stratigraphy analysis. Most likely, they formed during the initial flooding of Lake Van ~600ka. The Tatvan basin sediments are dominated by mass-flow deposits of various origins alternating with undisturbed lacustrine sediments including distinct tephra layers. Faulting along the Tatvan basin margins may have triggered margin-wide slope failures. Ahlat ridge started to form between ca340ka-290ka. Since then, Ahlat ridge was sheltered from major mass-flows due to its elevation. Hence, slow lacustrine sedimentation has prevailed throughout lake history on Ahlat ridge, which was the location of the main drill site during the ICDP. Several lake level fluctuations are evident on the eastern slope area but the deep basins were permanently covered by water. A significant lake-level low stand (ca600kaBP) was found at ~610m below present lake level. The setting of the lake changed at about 30ka. Tectonic activity appears to have waned significantly as the mass-transport deposition decreased across the Tatvan basin while normal undisturbed lacustrine sedimentation prevailed. A different setting is found in the Northern basin from ca90ka to Present, especially due to the strong influx of mostly volcaniclastic turbidites causing sedimentation rates to be about 3.5 times higher (drill Site 1), than at Site 2 (Ahlat ridge). © 2014 Elsevier Ltd. 2014 English 02773791 10.1016/j.quascirev.2014.07.016 Quaternary Science Reviews 104 Elsevier Ltd 63-84 GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, Kiel, 24148, Germany; Kiel University, Institute of Geosciences, Otto-Hahn-Platz 1, Kiel, 24118, Germany; Istanbul Technical University, EMCOL and Department of Geological Engineering, Maslak, Istanbul, 34469, Turkey; Van Yüzüncü Yil Univ., Department of Geological Engineering, Van, Turkey; Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Water Resources and Drinking Water, Überlandstrasse 133, Dübendorf, CH-8600, Switzerland; ETH Zurich, Climate Geology, Sonneggstrasse 5, Zurich, 8092, Switzerland Drills; Faulting; Infill drilling; Mass transfer; Sedimentation; Seismic waves; Seismology; Stratigraphy, Ahlat ridge; Lake vans; Northern basins; Seismic reflections; Tatvan basin, Lakes, delta; drilling; fault; geomorphology; lacustrine deposit; lake evolution; sedimentation; seismic reflection; seismic stratigraphy; turbidity, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84909636466&doi=10.1016%2fj.quascirev.2014.07.016&partnerID=40&md5=16e7366ec1bbd55cc26c074cb24ff4c5 cited By 27 D. Cukur S. Krastel H.-U. Schmincke M. Sumita M.N. Çağatay A.F. Meydan E. Damci M. Stockhecke article Litt20141 A complete succession of the lacustrine sediment sequence deposited during the last ~600,000 years in Lake Van, Eastern Anatolia (Turkey) was drilled in 2010 supported by the International Continental Scientific Drilling Program (ICDP). Based on a detailed seismic site survey, two sites at a water depth of up to 360m were drilled in summer 2010, and cores were retrieved from sub-lake-floor depths of 140m (Northern Basin) and 220m (Ahlat Ridge). To obtain a complete sedimentary section, the two sites were multiple cored in order to investigate the paleoclimate history of a sensitive semi-arid region between the Black, Caspian, and Mediterranean seas. This introductory paper provides background information of the deep drilling project and an overview of the studies presented in this special volume by the PALEOVAN science team dealing with chronology, paleomagnetism, paleoenvironmental proxies, geophysical and petrophysical investigations as well as pore-water and fluid transport. © 2014 Elsevier Ltd. 2014 English 02773791 10.1016/j.quascirev.2014.09.026 Quaternary Science Reviews 104 Elsevier Ltd 1-7 University of Bonn, Steinmann Institute of Geology, Mineralogy and Paleontology, Nussallee 8, Bonn, 53115, Germany; Institute of Geological Sciences and Oeschger Centre for Climate Change Research, University of Bern, Baltzerstrasse 1-3, Bern, 3012, Switzerland Deep drilling; Lake vans; Long continental record; Near East; Quaternary, deep drilling; lacustrine deposit; paleoclimate; Quaternary; sediment core; seismic survey; semiarid region, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84909643137&doi=10.1016%2fj.quascirev.2014.09.026&partnerID=40&md5=926d58105fc64bb301f18c9b94357564 cited By 33 T. Litt F.S. Anselmetti article Stockhecke20141830 The lithostratigraphic framework of Lake Van, eastern Turkey, has been systematically analysed to document the sedimentary evolution and the environmental history of the lake during the past ca 600 000 years. The lithostratigraphy and chemostratigraphy of a 219 m long drill core from Lake Van serve to separate global climate oscillations from local factors caused by tectonic and volcanic activity. An age model was established based on the climatostratigraphic alignment of chemical and lithological signatures, validated by 40Ar/39Ar ages. The drilled sequence consists of ca 76% lacustrine carbonaceous clayey silt, ca 2% fluvial deposits, ca 17% volcaniclastic deposits and 5% gaps. Six lacustrine lithotypes were separated from the fluvial and event deposits, such as volcaniclastics (ca 300 layers) and graded beds (ca 375 layers), and their depositional environments are documented. These lithotypes are: (i) graded beds frequently intercalated with varved clayey silts reflecting rising lake levels during the terminations; (ii) varved clayey silts reflecting strong seasonality and an intralake oxic-anoxic boundary, for example, lake-level highstands during interglacials/interstadials; (iii) CaCO3-rich banded sediments which are representative of a lowering of the oxic-anoxic boundary, for example, lake level decreases during glacial inceptions; (iv) CaCO3-poor banded and mottled clayey silts reflecting an oxic-anoxic boundary close to the sediment-water interface, for example, lake-level lowstands during glacials/stadials; (v) diatomaceous muds were deposited during the early beginning of the lake as a fresh water system; and (vi) fluvial sands and gravels indicating the initial flooding of the lake basin. The recurrence of lithologies (i) to (iv) follows the past five glacial/interglacial cycles. A 20 m thick disturbed unit reflects an interval of major tectonic activity in Lake Van at ca 414 ka bp. Although local environmental processes such as tectonic and volcanic activity influenced sedimentation, the lithostratigraphic pattern and organic matter content clearly reflect past global climate changes, making Lake Van an outstanding terrestrial archive of unprecedented sensitivity for the reconstruction of the regional climate over the last 600 000 years. © 2014 The Authors Sedimentology © 2014 International Association of Sedimentologists. 2014 English 00370746 10.1111/sed.12118 Sedimentology 61 Blackwell Publishing Ltd 1830-1861 Department of Surface Waters Research and Management, Swiss Federal Institute of Aquatic Science and Technology, Eawag, Ueberlandstrasse 133, P.O. Box 611, Dübendorf, 8600, Switzerland; Geological Institute, Swiss Federal Institute of Technology (ETH), Sonneggstrasse 5, Zurich, 8092, Switzerland; GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, Kiel, 24148, Germany; Swiss Federal Institute of Aquatic Science and Technology, Water Resources and Drinking Water, Eawag, Ueberlandstrasse 133, P. O. Box 611, Dübendorf, 8600, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology (ETH), Universitaetstrasse 16, Zurich, 8092, Switzerland; Institute of Geochemistry and Petrology, Swiss Federal Institute of Technology (ETH), Clausiusstrasse 25, Zurich, 8092, Switzerland; Institute of Geological Sciences and Oeschger Centre for Climate Change Research, University of Bern, Baltzerstrasse 1-3, Bern, 3012, Switzerland 6 Argon; Calcium carbonate; Climate change; Deposits; Environmental protection; Glacial geology; Lakes; Lithology; Oxic sediments; Sedimentology; Silt; Tectonics; Volcanoes, Continental archive; Eastern Anatolia; Glacial/interglacial climate; ICDP project PALEOVAN; Lake sediments; Palaeoenvironmental reconstruction, Anoxic sediments https://www.scopus.com/inward/record.uri?eid=2-s2.0-84907838297&doi=10.1111%2fsed.12118&partnerID=40&md5=9ec0ee07b1b95d9fc173585319b480f0 cited By 80 M. Stockhecke M. Sturm I. Brunner H.-U. Schmincke M. Sumita R. Kipfer D. Cukur O. Kwiecien F.S. Anselmetti article Vigliotti201418 In the framework of the PALEOVAN project, a high-resolution paleomagnetic and rock magnetic study was carried out on a 149m sedimentary sequence recovered from Ahlat Ridge in the deepest part of the Lake Van (Eastern Turkey; ICDP Site 5034-2). High sedimentation rates (average ~30cm/ka) allow high-resolution measurements of natural remanent magnetization (NRM), magnetic susceptibility (κ), anhysteretic remanence (ARM) and hence of anhysteretic susceptibility (κARM) over the last 350ka. The carrier of the remanence is detrital titanomagnetite largely from volcanic sources, based on the similarity of magnetite grain size of tephra layers and the other lacustrine lithologies observed in a plot of the κ versus κARM. Bulk magnetic parameters often covary with paleoclimatic signals in the Lake Van sediments. A correlation exists between variations of κ and ARM intensity and glacial-interglacial marine isotopic stages, as well as dust flux and temperatures observed in ice cores from Greenland and Antarctica. The quality of the paleomagnetic record is compromised by weak NRM intensities, as well as by the presence of tephra and turbidites throughout the sequence. Nonetheless, a correlation is observed between the relative paleointensity (RPI) record, based on NRM/ARM, and the calibrated PISO RPI stack, that supports the independently derived age model for the site. © 2014 Elsevier Ltd. 2014 English 02773791 10.1016/j.quascirev.2014.09.028 Quaternary Science Reviews 104 Elsevier Ltd 18-29 Istituto di Scienze Marine, ISMAR-CNR, Bologna, Italy; Department of Geological Sciences, University of Florida, Gainesville, FL 32611, United States; Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dept. of Surface Waters Dübendorf, Switzerland; ETH Zurich, Geological Institute, Zurich, Switzerland Lacustrine sediments; Lake vans; Late quaternary; Paleoclimates; Paleomagnetism, grain size; lacustrine deposit; magnetic intensity; magnetic susceptibility; natural remanent magnetization; paleoclimate; paleoenvironment; paleomagnetism; Quaternary; sedimentary sequence; sedimentation rate; tephra, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84909633301&doi=10.1016%2fj.quascirev.2014.09.028&partnerID=40&md5=3c7286d9bafe6cdef194b79434db494f cited By 25 L. Vigliotti J.E.T. Channell M. Stockhecke article Tomonaga2014117 Sediment samples acquired in 2010 from the long cores of the International Continental Scientific Drilling Program (ICDP) PaleoVan drilling project on Lake Van for noble-gas analysis in the pore water allow determination of the local terrestrial He-gradient as a function of depth within a sediment column of more than 200m. These measurements yield first insights into the physical transport mechanisms of terrigenic He through the uppermost part of unconsolidated lacustrine sediments overlying the continental crust.In line with our previous work on the spatial distribution of the terrigenic He release into Lake Van, we identify a high He concentration gradient in the uppermost 10m of the sediment column. The He concentration gradient decreases below this depth down to approx. 160. m following in general the expectations of the modelling of radiogenic He production and transport in a sediment column with homogeneous fluid transport properties. Overall the in-situ radiogenic He production due to the decay of U and Th in the mineral phases of the sediments accounts for about 80% of the He accumulation. At approx. 190. m we observe a very high He concentration immediately below a large lithological unit characterised by strong deformations. We speculate that this local enrichment is the result of the lower effective diffusivities in the pore space that relate to the abrupt depositional history of this deformed unit. This particular lithological unit seems to act as a barrier that limits the transport of solutes in the pore space and hence might "trap" information on the past geochemical conditions in the pore water of Lake Van.The dissolved concentrations of atmospheric noble gases in the pore waters of the ICDP PaleoVan cores are used to geochemically reconstruct salinity on the time scale of 0-55kaBP. Higher salinities in the pore water at a depth of about 20m suggest a significantly lower lake level of Lake Van in the past. © 2014 Elsevier Ltd. 2014 English 02773791 10.1016/j.quascirev.2014.09.005 Quaternary Science Reviews 104 Elsevier Ltd 117-126 Eawag, Swiss Federal Institute of Aquatic Science and Technology, Water Resources and Drinking Water, Duebendorf, Switzerland; Department of Geological Engineering, Yuzuncu Yil University, Van, Turkey; Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology, Zurich, Switzerland; Institute of Geochemistry and Petrology, Swiss Federal Institute of Technology, Zurich, Switzerland Inert gases; Infill drilling; Lakes; Lithology; Mineral industry; Solute transport; Water, Concentration gradients; Continental scientific drillings; Deep drilling; Dissolved concentrations; ICDP; Palaeo-salinity; Palaeoenvironmental reconstruction; PaleoVan, Sediments, continental crust; deep drilling; helium; lacustrine deposit; lithology; mineral; noble gas; paleoenvironment; paleosalinity; porewater; reconstruction; sediment analysis; sediment chemistry; solute transport, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84909580967&doi=10.1016%2fj.quascirev.2014.09.005&partnerID=40&md5=393326873e0c2c87ae342bddfdefd662 cited By 19 Y. Tomonaga M.S. Brennwald A.F. Meydan R. Kipfer article Stockhecke20148 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 166-m-long event-corrected 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 and synthesized Greenland ice-core stratigraphy. The chronology is constructed using 49 age control points derived from visual synchronization with the Greenland ice-core stratigraphy using the GICC05 timescale, an absolutely-dated speleothem timescale (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 three 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-m-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 ~90ka. 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 links ice-marine-terrestrial stratigraphies and that the 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 250ka can be used to test other dating techniques. © 2014 Elsevier Ltd. 2014 English 02773791 10.1016/j.quascirev.2014.04.008 Quaternary Science Reviews 104 Elsevier Ltd 8-17 Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Surface Waters Research and Management, Ueberlandstrasse 133, P.O.Box 611, Dübendorf, 8600, Switzerland; ETH, Geological Institute, Zurich Universitaetsstrasse 5, Zurich, 8092, Switzerland; Ruhr-University Bochum, Universitaetstrasse 150, Bochum, 44801, Germany; Istituto di Scienze Marine, ISMAR-CNR, Bologna, Italy; Institute of Geological Sciences and Oeschger Centre for Climate Change Research, University of Bern, Baltzerstrasse 1-3, Bern, 3012, Switzerland; Department of Geological Engineering, Eastern Mediterranean Centre for Oceanography and Limnology, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey; Department of Geological Sciences, University of Florida, Gainesville, FL 32611, United States; Swiss Federal Institute of Aquatic Science and Technology, Water Resources and Drinking Water, Eawag, Ueberlandstrasse 133, P. O. Box 611, D€ubendorf, 8600, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology (ETH), Universitaetstrasse 16, Zurich, 8092, Switzerland; Institute of Geochemistry and Petrology, Swiss Federal Institute of Technology (ETH), Clausiusstrasse 25, Zurich, 8092, Switzerland; Steinmann Institute of Geology, Mineralogy and Paleontology, Bonn University, Nussallee 8, Bonn, 53115, Germany Argon; Glacial geology; Ice control; Isotopes; Lakes; Organic carbon; Sediments; Single crystals; Stratigraphy, ICDP project PALEOVAN; Long terrestrial paleoenvironmental records; Magnetostratigraphy; Radiometric dating; Tephrostratigraphy, Ice, argon-argon dating; chronostratigraphy; lithostratigraphy; magnetostratigraphy; NorthGRIP; paleoclimate; Quaternary; radiometric method; sediment core; sediment property; sedimentary sequence; tephrochronology; total organic carbon, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84909639499&doi=10.1016%2fj.quascirev.2014.04.008&partnerID=40&md5=298981880bee7258373606b9ab54c676 cited By 71 M. Stockhecke O. Kwiecien L. Vigliotti F.S. Anselmetti J. Beer M.N. Çağatay J.E.T. Channell R. Kipfer J. Lachner T. Litt N. Pickarski M. Sturm article Çağatay201497 Sedimentary, geochemical and mineralogical analyses of the ICDP cores recovered from the Northern Basin (NB) of Lake Van provide evidence of lake level and climatic changes related to orbital and North Atlantic climate system over the last 90ka. High lake levels are generally observed during the interglacial and interstadial periods, which are marked by deposition of varved sediments with high total organic carbon (TOC), total inorganic carbon (TIC), low detrital influx (high Ca/F) and high δ18O and δ13C values of authigenic carbonate. During the glacial and stadial periods of 71-58kaBP (Marine Isotope Stage 4, MIS4) and end of last glaciation-deglaciation (30-14.5kaBP; MIS3) relatively low lake levels prevailed, and grey homogeneous to faintly laminated clayey silts were deposited at high sedimentation and low organic productivity rates.Millennial-scale variability of the proxies during 60-30kaBP (MIS3 is correlated with the Dansgaard-Oeschger (D-O)) and Holocene abrupt climate events in the Atlantic. These events are characterized by laminated sediments, with high TOC, TIC, Ca/Fe, δ18O and δ13C values. The Lake Van NB records correlate well in the region with the climate records from the lakes Zeribar and Urmia in Iran and the Sofular Cave in NW Anatolia, but are in general in anti-phase to those from the Dead Sea Basin (Lake Lisan) in the Levant. The relatively higher δ18O values (0 to-0.4‰) for the interglacial and interstadial periods in the Lake Van NB section are due to the higher temperature and seasonality of precipitation and higher evaporation, whereas the lower values (-0.8 to-2‰) during the glacial and stadial periods are caused mainly by relative decrease in both temperature and seasonality of precipitation. The high δ18O values (up to 4.2‰) during the Younger Dryas, together with the presence of dolomite and low TOC contents, supports evaporative conditions and low lake level. A gradual decrease in the δ18O values from an average of-0.4‰ during the humid early Holocene to an average of-3.5‰ during the more arid late Holocene suggests an increasing contribution of winter precipitation. The changes in the seasonality of precipitation in eastern Anatolia are probably caused by changes in the temperatures of North Atlantic and Mediterranean and in the strength of Siberian High. © 2014 Elsevier Ltd. 2014 English 02773791 10.1016/j.quascirev.2014.09.027 Quaternary Science Reviews 104 Elsevier Ltd 97-116 Istanbul Technical University, Eastern Mediterranean Centre for Oceanography and Limnology (EMCOL), Ayazağa Kampusu, Maslak, Istanbul, 34469, Turkey; Istanbul Technical University, Faculty of Mines, Geological Engineering Department, Turkey; Istanbul Technical University, Eurasia Institute of Earth Sciences, Turkey; Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Surface Waters Research and Management, Switzerland; ETH, Geological Institute, Zurich Universitaetsstrasse 5, Zurich, 8092, Switzerland; Firat University, Department of Geological Engineering, Elaziğ, Turkey Climate record; ICDP PaleoVan; Lake levels; Lake vans; Multproxy analyses; Northern basins, authigenesis; climate variation; Dansgaard-Oeschger cycle; Holocene; interstadial; lake level; marine isotope stage; paleoclimate; precipitation (climatology); proxy climate record, Anatolia; Atlantic Ocean; Iran; Kordestan; Lake Urmia; Lake Van; Lake Zeribar; Levant; Mediterranean Region; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84909599486&doi=10.1016%2fj.quascirev.2014.09.027&partnerID=40&md5=45d48abb11b99b381346a3ee8fb940b6 cited By 73 M.N. Çağatay N. Öğretmen E. Damci M. Stockhecke Ü. Sancar K.K. Eriş S. Özeren article Baumgarten201485 Lake Van (Turkey) is the 4th largest terminal lake in the world and is located at a key position for climatic reconstruction. The ICDP project 'PALEOVAN' is a deep-drilling campaign initiated in the summer of 2010 to enhance the understanding of paleoclimatic and paleoenvironmental conditions in the Middle East for a period of 550,000 years. Multiple coring of two sites (Northern Basin and Ahlat Ridge) at a water depth of up to 360m has been performed. The sedimentary record is mainly composed of clayey silts and tephra deposits that were supplied by four volcanic sources: 1) the Süphan volcano, located on the northern shore, 2) the Nemrut volcano, 15km west of the westernshore, 3) the Incekaya volcano, on the southwestern shore and 4) intralake eruptive centers. The dominant chemical composition of the volcanic sources is known from studies of land deposits.High-quality downhole logs have been acquired from both sites. To construct a continuous lithological profile, 180m of downhole logging data from the Ahlat Ridge have been analyzed by cluster analysis. To improve the differentiation of the sediments, two elemental intensity profiles from x-ray fluorescence core-scanning (calcium and zirconium) performed on the composite profile core material were added to the cluster analysis. Five cluster units were derived and transformed into three tephra and two clayey silt units. To compare the two clayey silt units with the composite profile from the visual core description (VCD) that showed 15 lithological units, the composite profile was classified into two major groups of lacustrine sediments: banded clayey silts (interpreted as glacial deposits) and laminated clayey silts (interpreted as interglacial deposits). Despite this simplification, no correlation between the two clayey silt units derived from cluster analysis and the banded and laminated clayey silts could be found. The following reasons are proposed: (a) the comparability of the datasets was limited by significant depth shifts of up to 2.5m between the composite profile based on the VCD and the downhole measurements in hole 2D of the Ahlat Ridge, (b) a correlation was difficult to ascertain from the vertical resolution of the downhole logging data and the extremely detailed core description in mm-scale, (c) mixed signals were obtained because of prevailing thin layers and intercalations of different lithotypes and (d) cluster analysis was difficult to perform because the contrast within the input data is too low (possibly background sedimentation) to distinguish between glacial and interglacial deposits. Tephra units are characterized by contrasting properties and differ mainly in their magnetic susceptibility, spectral gamma ray components (uranium, thorium and potassium) and XRF-intensities of calcium and zirconium. Tephra units have been linked to the dominant volcanic composition of the deposited tephra layers and partly to the volcanic sources. Depth trends are derived with prevailing basaltic deposits in the bottom part (128m-210m below lake floor) and are gradually outweighed by the highly differentiated (dacitic and rhyolitic/trachytic) products towards the top of the record. © 2014 Elsevier Ltd. 2014 English 02773791 10.1016/j.quascirev.2014.03.016 Quaternary Science Reviews 104 Elsevier Ltd 85-96 Leibniz Institute for Applied Geophysics (LIAG), Rock Physics and Borehole Geophysics, Stilleweg 2, Hannover, 30655, Germany Physical properties, Downholes; ICDP; Lake sediments; Paleoclimates; PALEOVAN; Quaternary; Tephra, Cluster analysis, basalt; chemical composition; clay; cluster analysis; depositional environment; facies; lacustrine deposit; paleoclimate; paleolimnology; physical property; Pleistocene; sediment core; sedimentation; silt; tephra; volcanic eruption; volcanogenic deposit; well logging, Lake Van; Turkey; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84909585607&doi=10.1016%2fj.quascirev.2014.03.016&partnerID=40&md5=b8e3d209b32fd9d0a2033adedcf27532 cited By 10 H. Baumgarten T. Wonik O. Kwiecien article Kwiecien201442 A well-dated suite of Lake Van climate-proxy data covering the last 360ka documents environmental changes over 4 glacial/interglacial cycles in Eastern Anatolia, Turkey. The picture of cold and dry glacials and warm and wet interglacials emerging from pollen, organic carbon, authigenic carbonate content, elemental profiling by XRF and lithological analyses is inconsistent with classical interpretation of oxygen isotopic composition of carbonates pointing to a more complex pattern in Lake Van region. Detailed analysis of glacial terminations allows for the constraining of a depositional model explaining different patterns observed in all the proxies. We hypothesize that variations in relative contribution of rainfall, snowmelt and glacier meltwater recharging the basin have a very important role for all sedimentary processes in Lake Van. Lake level of glacial Lake Van, predominantly fed by snowmelt, was low, the water column was oxic, and carbonates precipitating in the epilimnion recorded the light isotopic signature of inflow. During terminations, increasing rainfall and significant supply of mountain glaciers' meltwater contributed to lake level rise. Increased rainfall enhanced density gradients in the water column, and hindered mixing leading to development of bottom-water anoxia. Carbonates precipitating during terminations show large fluctuations in their isotopic composition. Full interglacial conditions in Lake Van are characterized by high or slowly falling lake level. Rainfall and snowmelt feed the lake but due tore-established mixing, the isotopic composition of authigenic carbonates is heavier and closer to that of evaporation-influenced lake water than that of runoff representing snowmelt and atmospheric precipitation. © 2014 Elsevier Ltd. 2014 English 02773791 10.1016/j.quascirev.2014.07.001 Quaternary Science Reviews 104 Elsevier Ltd 42-52 ETH Zurich, Climate Geology, Sonneggstrasse 5, Zurich, 8092, Switzerland; Eawag Dubendorf, Ueberlandstrasse 130, Duebendorf, 8600, Switzerland; Steinmann Institute of Geology, Mineralogy and Paleontology, Bonn University, Nussallee 8, Bonn, 53115, Germany; Institute of Geological Sciences and Oeschger Centre for Climate Change Research, University of Bern, Baltzerstrasse 1-3, Bern, 3012, Switzerland Carbonates; Glacial geology; Isotopes; Lithology; Mixing; Organic carbon; Rain; Snow melting systems, Eastern Mediterranean; Glacial/interglacial cycle; Lake vans; Multi proxies; Oxygen isotopes; Termination, Lakes, anoxia; carbonate; epilimnion; glacial environment; glacial-interglacial cycle; isotopic composition; lithology; numerical model; oxygen isotope; paleoclimate; proxy climate record; rainfall; runoff; snowmelt, Anatolia; Lake Van; Mediterranean Sea; Mediterranean Sea (East); Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84909598325&doi=10.1016%2fj.quascirev.2014.07.001&partnerID=40&md5=0d12c4a591b3dde8afac1e774afc753b cited By 45 O. Kwiecien M. Stockhecke N. Pickarski G. Heumann T. Litt M. Sturm F. Anselmetti R. Kipfer G.H. Haug article Acarel20144519 Monitoring coseismic velocity changes is a major challenge, since the Earth crust has to be uniformly sampled at preseismic, coseismic, and postseismic stages using repeating active or natural sources. Here we investigate the crustal response to the 2011 Van/Turkey earthquake using ambient noise, which provides the best possible temporal resolution. Combined recordings from the nearest five broadband stations are analyzed for a time period of 6 months framing the main shock. We observe a coseismic velocity decrease of up to 0.76% in the vicinity of the main shock in the frequency range of 0.05-0.3 Hz. The velocity drop is largest at close proximity to the earthquake hypocenter and decreases systematically with distance. We also find a correlation between coseismic velocity decrease and the amount of coseismic slip on the rupture plane. The observed velocity drop shows the drastic response of the brittle crust in response to a major earthquake. Key Points A coseismic velocity change The 2011 Van earthquake Scaling between the velocity change and slip ©2014. American Geophysical Union. All Rights Reserved. 2014 English 00948276 10.1002/2014GL060624 Geophysical Research Letters 41 Blackwell Publishing Ltd 4519-4526 GFZ German Research Centre for Geosciences, Potsdam, Germany; Institute of Geological Sciences, Free University Berlin, Berlin, Germany; Earthquake Department, Turkish Republic Disaster and Emergency Management Presidency, Ankara, Turkey 13 Acoustic noise; Drops; Earthquakes; Structural geology, 2011 Van earthquake/Turkey; Ambient noise; Broadband station; Close proximity; Coseismic slips; Frequency ranges; Temporal resolution; Velocity changes, Velocity https://www.scopus.com/inward/record.uri?eid=2-s2.0-84903861810&doi=10.1002%2f2014GL060624&partnerID=40&md5=df46322bafcb2f0d7f2624f93651eb67 cited By 10 D. Acarel F. Bulut M. Bohnhoff R. Kartal article Randlett201453 Fossil long-chain alkenones have been used for several decades to reconstruct past ocean surface water temperatures and gained recent interest as a paleotemperature proxy for continental lake settings. However, factors besides temperature can affect alkenone distributions in haptophyte algae, and alkenone compositions can differ between haptophyte species. Alkenone-biosynthesizing haptophyte algae are genetically much more diverse in lakes than in the marine realm, and species-level variations in alkenone compositions could have implications for alkenone paleothermometry. Here, we performed a paired analysis of alkenone distributions and haptophyte species compositions using ancient DNA in up to 270ka-old sediments of Lake Van in Turkey to reveal a possible species-effect on fossil alkenone distributions and paleotemperature estimates. The same predominant haptophyte in Lake Van today prevailed also since the last ~100ka. However, a calibration of alkenone paleotemperature especially in the oldest analyzed intervals is complicated due to a more complex haptophyte species composition predominated by a haptophyte (LVHap_6), which is phylogenetically different from sequences recovered from currently existing lakes including Lake Van and from haptophyte species existing in culture. The predominance of LVHap_6 coincided with the presence of alkenone MeC38:3 and relatively high MeC37:3/4 (2.4) and MeC38:4/5 ratios (3.0). Uk37 index values in the sediment core over the last 270ka reflect relative changes in past temperature and are additionally linked to haptophyte species composition. A sustained period of high salinity, as indicated by pore-water salinity measurements, could potentially have triggered the succession of haptophytes as sources of alkenones in Lake Van. © 2014 The Authors. 2014 English 02773791 10.1016/j.quascirev.2014.07.009 Quaternary Science Reviews 104 Elsevier Ltd 53-62 Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Surface Waters - Research and Management, Kastanienbaum, 6047, Switzerland; ETH Zurich, Institute of Biogeochemistry and Pollutant Dynamics, Zurich, 8092, Switzerland; WHOI Woods Hole Oceanographic Institution, Marine Chemistry and Geochemistry Department, Woods Hole, MA 02543, United States; Eawag, Department of Surface Water - Research and Management, Dübendorf, 8600, Switzerland; University of Bonn, Steinmann Institute of Geology, Mineralogy and Paleontology, Bonn, 53115, Germany; Eawag, Water Resources and Drinking Water, Dübendorf, 8600, Switzerland Algae; Biomarkers; Lakes; Paleolimnology; Salinity measurement; Sediments, Alkenones; Haptophyte species; Lake vans; Long chain alkenones; Paleoproxy; Paleotemperature proxy; Paleotemperatures; Species composition, Population distribution, alga; alkenone; biomarker; fossil record; lacustrine deposit; paleolimnology; paleotemperature; reconstruction; spatial distribution; temperature effect, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84909579815&doi=10.1016%2fj.quascirev.2014.07.009&partnerID=40&md5=46666f3d94df8cd717554da0f7778d25 cited By 59 M.-E. Randlett M.J.L. Coolen M. Stockhecke N. Pickarski T. Litt C. Balkema O. Kwiecien Y. Tomonaga B. Wehrli C.J. Schubert article Litt201430 Lake Van is the fourth largest terminal lake in the world (38.5°N, 43°E, volume 607km3, area 3570km2, maximum water depth 460m), extending for 130km WSW-ENE on the eastern Anatolian high plateau, Turkey. The sedimentary record of Lake Van, partly laminated, obtains a long and continuous continental sequence that covers multiple interglacial-glacial cycles. Promoted by the potential of the sedimentary sequence for reconstructing the paleoecological and paleoclimate development of the Near East, a deep drilling operation was carried out in 2010 supported by the International Continental Scientific Drilling Program (ICDP). The 219m long continental pollen record presented here is based on a well-dated composite profile drilled on the so-called Ahlat Ridge in water depth of 360m encompassing the last 600,000 years. It is the longest continuous continental pollen record of the Quaternary in the entire Near East and central Asia obtained to date. The glacial-interglacial cycles and pronounced interstadials are clearly reflected in the vegetation development based on millennial-scale time resolution. In general, the glacial/stadial vegetation is characterized by dwarf-shrub steppe and desert steppe, whereas the climax vegetation of past interglacials can be described as oak steppe-forest similar to the present interglacial in this sensitive semi-arid region between the Black, Caspian, and Mediterranean Seas. By comparing the Lake Van pollen record with other western Asian and southern European long continental pollen sequences as well as marine and ice-core records, the regional variability of the climate signals is also discussed. © 2014. 2014 English 02773791 10.1016/j.quascirev.2014.03.017 Quaternary Science Reviews 104 Elsevier Ltd 30-41 University of Bonn, Steinmann Institute of Geology, Mineralogy and Paleontology, Nussallee 8, Bonn, 53115, Germany; Swiss Federal Institute of Technology Zurich (ETH), Climate Geology, Sonneggstr. 5, Zurich, 8092, Switzerland; Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Surface Waters Research and Management, Ueberlandstrasse 133, Dübendorf, 8600, Switzerland; Department of Geography, University College London, London, United Kingdom Eastern Anatolia; Lake vans; Long continental pollen record; Near East; Paleoclimates, climax; deciduous tree; deep drilling; glacial-interglacial cycle; ice core; paleoclimate; paleoecology; palynology; Quaternary; sedimentary sequence; water depth, Black Sea; Caspian Sea; Lake Van; Mediterranean Sea; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84909584452&doi=10.1016%2fj.quascirev.2014.03.017&partnerID=40&md5=efa73281f2c080bc4042679baeaf4802 cited By 108 T. Litt N. Pickarski G. Heumann M. Stockhecke P.C. Tzedakis article Schmincke2014195 Fifteen Lateglacial to Holocene rhyolitic, dominantly primary tephra layers piston-cored and drilled (ICDP Paleovan drilling project) in western Lake Van (eastern Anatolia, Turkey) were precisely correlated to either of the two adjacent and active large volcanoes Nemrut and Süphan based on shard textures, mineralogy and mineral and glass compositions. The young peralkaline (comenditic to pantelleritic) primary rhyolitic Nemrut tephras are characterized by anorthoclase, hedenbergitic to augitic clinopyroxene, fayalitic olivine, minor quartz, and rare accessory chevkinite and zircon. Phenocrysts in subalkaline primary rhyolitic Süphan tephras are chiefly oligoclase-labradorite, with minor K-rich sanidine in some, biotite, amphibole, hypersthene, rare augitic clinopyroxene, relatively common allanite and rare zircon.Two contrasting explosive eruptive modes are distinguished from each other: episodic (Süphan) and periodic (Nemrut). The Lateglacial Süphan tephra swarm covers a short time interval of ca. 338. years between ca. 13,078. vy BP and 12,740. vy BP, eruptions having occurred statistically every ca. 42. years with especially short intervals between V-11 (reworked) and V-14. Causes for the strongly episodic Süphan explosive behavior might include seismic triggering of a volcano-magma system unable to erupt explosively without the benefit of external triggering, as reflected in pervasive faulting preceding the Süphan tephra swarm. Seismic triggering may have caused the rise of more mafic ("trachyandesitic") parent magma, heating near-surface pockets of highly evolved magma - that might have formed silicic domes during this stage of volcano evolution - resulting in ascent and finally explosive fragmentation of magma essentially by external factors, probably significantly enhanced by magma-water/ice interaction.Explosive eruptions of the Nemrut volcano system, interpreted to be underlain by a large fractionating magma reservoir, follow a more periodic mode of (a) long-term relatively constant supply of parent magma, (b) evolution by low pressure crystal fractionation resulting in sporadic relatively low-volume eruption of trachytic and minor rhyolitic magmas, (c) evolution of a large magma reservoir to the point of highly explosive large-volume peralkaline rhyolitic Plinian eruptions at temporal intervals of ca. 20-40. ky, some accompanied by ignimbrites and inferred caldera collapse.A striking tephra gap between ca. 14. ka and ca. 30. ka, i.e. during glacial climate conditions, is postulated to be due to climate-forcing via lithosphere unloading following deglaciation. © 2014 Elsevier B.V. 2014 English 03770273 10.1016/j.jvolgeores.2014.08.015 Journal of Volcanology and Geothermal Research 285 Elsevier 195-213 GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, Kiel, 24148, Germany Explosive activity; Lake vans; Tephra swarm; Tephrostratigraphy; Volcanic activities, climate forcing; earthquake trigger; explosive volcanism; Holocene; late glacial; stratigraphy; tephra; volcanic eruption, Anatolia; Bitlis; Lake Van; Nemrut; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84907818833&doi=10.1016%2fj.jvolgeores.2014.08.015&partnerID=40&md5=786e9e367748740c3ccbbb33e85460e1 cited By 26 H.-U. Schmincke M. Sumita article Cukur2013571 This paper presents results of a multi-channel seismic reflection survey at Lake Van and provides constraints on the sedimentary evolution of the lake. The geophysical data of the lake confirm the existence of three physiographic provinces: a shelf, a slope, and a deep, relatively flat basin. The most prominent features identified on the shelf and slope are clinoforms, submerged channels, as well as closely spaced lake floor depressions, reflecting a highly variable lake-level history. The morphological depressions are interpreted as resulting from subaquatic erosion by channelized, sediment-laden currents into horizontally bedded fan sediments. Submerged channels on the eastern shelf are interpreted as meandering-slope channels, probably as a consequence of a lake-level fall that exposed the shelf area. Clinoforms on the Eastern fan may represent relict deltas formed during stationary or slightly rising lake-level intervals. Merging subsurface imaging interpretation with morphological studies of exposed sediments reveals lake-level fluctuations of several hundreds of meters during the past ca. ~550 ka. The lake has three prominent basins (Tatvan, Deveboynu, and the Northern basin) separated by basement ridges (e. g., the Northern ridge). The seismic units in the Tatvan and Northern basins are dominated by alternations of well-stratified and chaotic reflections, while the Deveboynu basin subsurface consists mainly of chaotic units. The chaotic seismic facies are interpreted as mass-flow deposits, probably triggered by earthquakes and/or rapid lake-level fluctuations. The moderate-to-high-amplitude, well-stratified facies seen in the deeper parts of the basins are interpreted as lacustrine deposits intercalated with tephra layers. The occurrence of a clinoform in the deepest part of the lake suggests a major flooding stage of Lake Van more than ~400 ka ago. Seismic profiles from the deepest part of the lake basin show remarkably uniform and continuous stratigraphic units without any major erosional feature following the flooding event, indicating that the lake was never completely dry afterward and therefore significantly older than previously suggested. © 2012 Springer-Verlag. 2013 English 14373254 10.1007/s00531-012-0816-x International Journal of Earth Sciences 102 Springer Verlag 571-585 GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148 Kiel, Germany; Department of Geosciences, University of Bremen, Bremen, Germany; Department of Geophysical Engineering, Istanbul Technical University, Ayazaga Campus, Maslak-Istanbul, Turkey; Alfred Wegener Institute for Polar and Marine Research, 27515 Bremerhaven, Germany; Eurasia Institute of Earth Sciences, Istanbul Technical University, Ayazaga Campus, Maslak-Istanbul, Turkey 2 erosion; lacustrine deposit; lake level; sedimentary sequence; seismic reflection; tephra, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84874019371&doi=10.1007%2fs00531-012-0816-x&partnerID=40&md5=4d7b435f4bfe02c2db9f10fe7f64d573 cited By 39 D. Cukur S. Krastel F. Demirel-Schlüter E. Demirbag C. Imren M. Toker article Cukur2013341 Analysis of multi-channel seismic reflection and chirp data from Lake Van (eastern Turkey) reveals various shallow gas indicators including seismic chimneys, enhanced reflections, bright spots, mud volcanoes, pockmarks, and acoustic blanking. The enhanced reflections, suggesting the presence of free gas, are most dominant and observed at more than 200 locations. They are characterized by very-high amplitude reflections and occur in both deep and shallow sedimentary sections. Some enhanced reflections are accompanied by very subtle seafloor expressions such as mounds, which may suggest active venting activity. Seismic chimneys or columnar zones of amplitude blanking have been observed in much of the surveyed area. Seismic chimneys in the study area cannot be associated with any known faults that would act as migration pathways for deep fluids. This suggests that the observed structures in Lake Van sediments allow the preferential emission of gases which might be for a large share of biogenic origin. The acoustic blanking, characterized by transparent or chaotic seismic facies, is seen in the eastern part of the lake. The lakeward edge of the acoustic blanking largely coincides with the 100m water depth contour, indicating that (past) changes of the hydrostatic pressure may be responsible for the distribution of these anomalies. Mound-like features, interpreted as mud volcanoes, occur in a few locations. The presence of these features may suggest active gas emission. Very strong amplitude anomalies or bright spots with negative polarity, indicating gas-charged zones, are also seen in a number of locations. Pockmarks are observed only in the northeastern part of the study area. The scarce occurrence of pockmarks in the study area might be ascribed to a higher permeability of the lake sediments or to the absence of the substrate/reservoir providing the critical mass of gases necessary to produce such features. Turbidites, tephra layers, and deltaic deposits have the potential to provide ideal conditions to allow the sediments to act as a gas reservoir. © 2013 Elsevier Ltd. 2013 English 02648172 10.1016/j.marpetgeo.2013.08.017 Marine and Petroleum Geology 48 341-353 GEOMAR, Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148 Kiel, Germany; Kiel University, Institute of Geosciences, Otto-Hanhn-Platz 1, 24118 Kiel, Germany; Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Water Resources and Drinking Water, Überlandstrasse 133, CH-8600 Dübendorf, Switzerland; Istanbul Technical University, EMCOL and Department of Geological Engineering, 34469 Maslak, Istanbul, Turkey; Van Yüzüncü Yil Univ., Department of Geological Engineering, Van, Turkey Bright spots; Enhanced reflections; Lake vans; Pockmarks; Shallow gas, Chimneys; Hydrostatic pressure; Lakes; Sediments; Seismology; Volcanoes, Gases, deltaic deposit; facies analysis; hydrocarbon reservoir; hydrostatic pressure; lacustrine deposit; mud volcano; permeability; pockmark; seismic reflection; tephra; turbidite; venting, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84884564316&doi=10.1016%2fj.marpetgeo.2013.08.017&partnerID=40&md5=7ee3c5446147d3f708c7c35ae8435cc8 cited By 24 D. Cukur S. Krastel Y. Tomonaga M.N. Çağatay A.F. Meydan article Glombitza2013 As part of the International Continental Drilling Program deep lake drilling project PaleoVan, we investigated sulfate reduction (SR) in deep sediment cores of the saline, alkaline (salinity 21.4%, alkalinity 155 m mEq-1, pH 9.81) Lake Van, Turkey. The cores were retrieved in the Northern Basin (NB) and at Ahlat Ridge (AR) and reached a maximum depth of 220 m. Additionally, 65-75 cm long gravity cores were taken at both sites. SR rates (SRR) were low (≥22 nmol cm-3 day-1) compared to lakes with higher salinity and alkalinity, indicating that salinity and alkalinity are not limiting SR in Lake Van. Both sites differ significantly in rates and depth distribution of SR. In NB, SRR are up to 10 times higher than at AR. SR could be detected down to 19 mblf (meters below lake floor) at NB and down to 13 mblf at AR. Although SRR were lower at AR than at NB, organic matter (OM) concentrations were higher. In contrast, dissolved OM in the pore water at AR contained more macromolecular OM and less low molecular weight OM. We thus suggest, that OM content alone cannot be used to infer microbial activity at Lake Van but that quality of OM has an important impact as well. These differences suggest that biogeochemical processes in lacustrine sediments are reacting very sensitively to small variations in geological, physical, or chemical parameters over relatively short distances. © 2013 Glombitza, Stockhecke, Schubert, Vetter and Kallmeyer. 2013 English 1664302X 10.3389/fmicb.2013.00209 Frontiers in Microbiology 4 Frontiers Research Foundation Geomicrobiology Group, Institute of Earth and Environmental Sciences, University of Potsdam, Potsdam, Germany; Department of Surface Waters-Research and Management, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dubendorf, Switzerland; Department of Surface Waters-Research and Management, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Kastanienbaum, Switzerland; Section 4.3 Organic Geochemistry, Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Potsdam, Switzerland; Section 4.5 Geomicrobiology, Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany; Center for Geomicrobiology, Aarhus University, Ny Munkegade 114, 8000 Aarhus, Denmark JUL organic matter; sulfate, alkalinity; article; biogeochemical cycling; biosphere; carbon nitrogen ratio; ion pair chromatography; lake ecosystem; limit of quantitation; macromolecule; mathematical model; microbial activity; nonhuman; particle resuspension; pH measurement; reduction; reduction kinetics; relative density; salinity; sedimentology; sulfate reduction; total organic carbon; water sampling https://www.scopus.com/inward/record.uri?eid=2-s2.0-84885341712&doi=10.3389%2ffmicb.2013.00209&partnerID=40&md5=48044a2e841ce99204d1cabc98342e68 cited By 37 C. Glombitza M. Stockhecke C.J. Schubert A. Vetter J. Kallmeyer article Sumita201315 Thirty-two new single crystal ages document 400. 000. years of widespread explosive volcanism of historically active Nemrut Volcano towering over huge alkaline Lake Van (Eastern Anatolia). The dated deposits were selected to monitor the volcanic and compositional evolution of Nemrut Volcano through time and thus to provide a rigorous temporal framework for the tephra record of the PaleoVan Drilling Project. Tephra samples were taken from large-volume deposits or those that occur in medial to distal localities, well-exposed stratigraphic sections or from the initial phase of an eruptive sequence. Mainly fallout deposits were chosen because most ignimbrites show more complex and corroded feldspar populations owing to compositional zoning and magma mixing. Moreover, fallout deposits held the promise to be more clearly identifiable with-and correlatable to->. 300 tephra layers in the PaleoVan drill cores, even though commonly in amounts marginal or insufficient in thickness to allow well-supported single crystal dating. The crystals dated are dominantly anorthoclase, the main phenocryst phase in the trachytic to rhyolitic, slightly to strongly peralkaline Nemrut magmas. Ages obtained so far range from ca. 400. ka to ca. 30. ka for Nemrut Volcano. The causes of significant changes in the frequency, volume and composition of tephra layers per unit time are discussed in terms of external (erosion, climate changes, geodynamic factors) and internal forcing (changes in magma supply and composition and incubation periods preceding large volume rhyolitic eruptions). For example, the low frequency of tephra layers deposited prior to ca. 200. ka may be due to low explosive activity, severe erosion between MIS 9 and MIS 11, or both. Nevertheless, the overall frequency of explosive eruptions appears to have increased during the past ca. 200. ka. We also recognize a slight peak in explosive eruptions during warm periods (e.g. MIS 5 and MIS 7) and speculate on lithospheric unloading triggering increased partial melting or magma reservoir unloading following massive glacier melting. The ages of 5 dated ignimbrites span ca. 250. 000. years suggesting that Nemrut Volcano went through a polycyclic evolution with multiple caldera collapses and major pyroclastic flow eruptions, the oldest dated so far as 265. ka. The widely held view of the impressive Nemrut Caldera now dated to have formed at ca. 30. ka, as the main paroxysmal event during the evolution of the volcano is no longer tenable. Distinct and coherent compositional characteristics, especially in trace element concentrations, characterize several groups of trachytic tephras. We speculate that the growth of Nemrut Volcano caused the isolation of the Lake Van basin. On account of their mineralogical (anorthoclase, hedenbergite, fayalite, aenigmatite) and alkalic chemical compositions and large volume, dated Nemrut fallout tephras are likely to represent excellent markers in lakes and other sites of paleoclimatological or archeological interest in neighboring countries to the northeast of Lake Van as far as the Caspian Sea in what may be called the East Anatolian Tephra Province. © 2012 Elsevier B.V. 2013 English 03770273 10.1016/j.jvolgeores.2012.12.009 Journal of Volcanology and Geothermal Research 253 Elsevier B.V. 15-34 GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148 Kiel, Germany Alkalinity; Climate change; Deposits; Erosion; Explosives; Fallout; Feldspar; Feldspar deposits; Lakes; Melting; Reservoirs (water); Single crystals; Stratigraphy; Submarine geophysics; Trace elements; Unloading, Chemical compositions; Compositional characteristics; Compositional evolution; Compositional zoning; East Anatolian Tephra Province; Explosive volcanism; Lake vans; Trace element concentrations, Volcanoes, argon-argon dating; explosive volcanism; ignimbrite; marine isotope stage; pyroclastic flow; temporal evolution; tephra; volcanic eruption, Bitlis; Lake Van; Nemrut; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84872554483&doi=10.1016%2fj.jvolgeores.2012.12.009&partnerID=40&md5=19be418557701f4821eb93d4f3ea42f4 cited By 51 M. Sumita H.-U. Schmincke article Sumita20131 The historically active Nemrut Volcano (2,948 m asl) (Eastern Anatolia), rising close to the western shore of huge alkaline Lake Van, has been the source of intense Plinian eruptions for &gt;530,000 years (drilled lake sediments). About 40 widespread, newly recognized trachytic and less common rhyolitic fallout tephras and ca. 12 interbedded ignimbrites, sourced in Nemrut Volcano, are documented in stratigraphic traverses throughout an area of &gt;6,000 km2 mostly west of Lake Van. Phenocrysts in the moderately peralkaline trachytes and rarer large-volume comenditic rhyolites comprise anorthoclase, hedenbergite-augite, fayalite and, especially in trachytic units, augite, minor aenigmatite, apatite and quartz, and rare chevkinite and zircon. Dacitic to rhyolitic tephras from nearby calcalkalic Süphan Volcano (4,058 m asl), locally interbedded with Nemrut tephras, are characterized by disequilibrium phenocryst assemblages (biotite, augitic clinopyroxene and hypersthene, minor olivine, common crystal clots and/or, in some deposits, amphibole). The magma volume (DRE) of the largest Nemrut tephra sheet (AP-1) described in detail may exceed 30 km3. Extreme facies and systematic compositional changes are documented in the ca. 30 ka Nemrut Formation (NF) deposits formed from one large and complex eruption (thick rhyolitic fallout overlain by ignimbrite, welded agglutinate, overbank surge deposits, and final more mafic fallout deposits). Common evidence of magma mixing in Nemrut ignimbrites reflects eruption from compositionally zoned magma reservoirs. Several young Çekmece Formation trachytes overlying ca. 30 ka old NF deposits and the late trachytes of the NF deposits show compositional affinities to tephra from Süphan Volcano possibly due to temporary influx of Süphan magmas into the Nemrut system following the evacuation of &gt;10 km3 magma (DRE) during the caldera-forming NF eruption. Axes of large fallout fans are dominantly SW-NE but W-E in the younger sheets resembling the direction of the present dominant wind field. Growth of Nemrut volcanic edifice and its peripheral domes since before 0.5 Ma in the hinge area between the Van and Muş tectonic basins is likely to have been the major factor in isolating Lake Van basin thus initiating the origin and subsequent alkaline evolution of the lake. This alkalinity was later significantly controlled by climate forcing. Internal forcing mechanisms (volcanic and geodynamic) may also have contributed to major lake level changes in addition to climate forcing. © 2013 Springer-Verlag Berlin Heidelberg. 2013 English 02588900 10.1007/s00445-013-0714-5 Bulletin of Volcanology 75 Springer Verlag 1-32 GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1, 24148 Kiel, Germany 5 basin evolution; ignimbrite; lithostratigraphy; peralkaline rock; phenocryst; plinian eruption; rhyolite; tephra; trachyte; volcanic eruption; volcanism, Bitlis; Lake Van; Nemrut; Turkey, Plinia; Trachytes https://www.scopus.com/inward/record.uri?eid=2-s2.0-84876681356&doi=10.1007%2fs00445-013-0714-5&partnerID=40&md5=196eeb628c8510172b636594a10381a8 cited By 49 M. Sumita H.-U. Schmincke article Sumita2013131 1 Corrections in Table 1 and Fig. 10 The attached Table 2 and Fig. 10 should replace the original Table 1 and Fig. 10. 1.1 Correction details in Table 2 1.2 Correction details in Fig. 10 2 Corrections in the text body The corrections in Table 2 necessitate the following slight changes in the text body (pages 22–29) 4.1.8. (page 23): Replace “Pantelleritic rhyolite” with “Comenditic rhyolite”. 4.1.20. (page 27): Replace “Trachyte” with “Comenditic rhyolite”. 4.1.21. (page 28): Replace “Pantelleritic rhyolite” with “Comenditic rhyolite”. 4.2.3. (page 28): Replace “Comenditic rhyolite” with “Comenditic rhyolite to trachyte”. 4.2.4. (page 28): Replace “Pantelleritic rhyolite” with “Comenditic rhyolite”. 4.2.6. (page 29): Replace “Trachyte” with “Comenditic rhyolite”. © 2013 Elsevier B.V. 2013 English 03770273 10.1016/j.jvolgeores.2013.01.008 Journal of Volcanology and Geothermal Research 253 Elsevier B.V. 131-133 GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, Kiel, 24148, Germany https://www.scopus.com/inward/record.uri?eid=2-s2.0-84873403986&doi=10.1016%2fj.jvolgeores.2013.01.008&partnerID=40&md5=3b20f97cd3218a31dbf4f649982dbfba cited By 19 M. Sumita H.-U. Schmincke article Litt201218 International Continental Scientific Drilling Program (ICDP) drilled a complete succession of the lacustrine sediment sequence deposited during the last -500,000 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 paleoclimate 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 deposition of tephra layers. The sediments host organic matter from different sources and hence composition, which will be unravelled using biomarkers. Pathways for migration of continental 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. 2012 English 18168957 10.5194/sd-14-18-2012 Scientific Drilling Copernicus GmbH 18-29 Steinmann Institute of Geology, Mineralogy and Paleontology, Bonn University, Bonn, Germany; GEOMAR, Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148 Kiel, Germany; Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf and Kastanienbaum, Switzerland; Yüzüncü Yil Üniversitesi, Mühendislik - Mimarlik Fakultesi Jeoloji Mühendisliǧi Bölümü, Van, Turkey; Department of Geological Engineering and Eastern Mediterranean, Centre for Oceanography and Limnology, Istanbul Technical University, Istanbul, Turkey; Leibniz-Institute for Applied Geophysics (LIAG), Hannover, Germany; Potsdam University, Institute for Earth and Environmental Sciences, Geomicrobiology Group, Potsdam, Germany; Istituto di Scienze Marine, ISMAR, CNR, Bologna, Italy 14 Inert gases; Lakes; Sediments; Single crystals, Compositional evolution; Continental scientific drillings; Drilling projects; Earthquake activity; Environmental history; Lacustrine sediments; Mediterranean sea; Semi-arid region, Infill drilling https://www.scopus.com/inward/record.uri?eid=2-s2.0-84867822516&doi=10.5194%2fsd-14-18-2012&partnerID=40&md5=e8787e1c49e6431fd49a21f3fb0418e7 cited By 37 T. Litt F.S. Anselmetti H. Baumgarten J. Beer N. Cagatay D. Cukur E. Damci C. Glombitza G. Haug G. Heumann J. Kallmeyer R. Kipfer S. Krastel O. Kwiecien A. Feray Meydan S. Orcen N. Pickarski M.-E. Randlett H.-U. Schmincke C.J. Schubert M. Sturm M. Sumita M. Stockhecke Y. Tomonaga L. Vigliotti T. Wonik article Huguet20123628 Lake Van in Turkey is the world's largest soda lake (607 km3). The lake's catchment area is estimated to be ~12,500 km2, and the terrestrial input is carried through eolian, riverine, snowmelt and anthropogenic paths. Extent and seasonality of the terrestrial inputs to the lake have not been studied, but it is essential to evaluate its environmental status and to assess the use of environmental proxies to estimate the lake's response to climate changes. This study aims to measure seasonal changes in terrestrial input of natural and anthropogenic origin as recorded by the fluxes of pollen and biomarkers of soil bacteria and vascular or higher plants, as well as petrogenic biomarkers in monthly resolved sediment traps from August 2006 to July 2007. Fluxes of pollen, soil and higher plant biomarkers seem to be related to precipitation and snowmelt in autumn and spring. In addition, dust storms, which are common during the summer months, may have resulted in long-distance transport. Anthropogenic biomarker fluxes indicate year-round petrogenic contamination although some mature biomarker fluxes are higher in summer and in late winter-spring. The relative changes between petrogenic markers indicate variations in the pollutant sources. © 2012 Springer-Verlag. 2012 English 09441344 10.1007/s11356-012-0948-3 Environmental Science and Pollution Research 19 3628-3635 Institut de Ciència i Tecnologia Ambientals (ICTA), Universitat Autònoma de Barcelona (UAB), Edifici CN, torre C5, 4a planta, Campus UAB, 08193 Bellaterra, Spain; Steinmann Institute of Geology, Mineralogy and Palaeontology, University of Bonn, Bonn, Germany; Department of Surface Water Research and Management, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Uberlandstrasse 133, 8600 Dubendorf, Switzerland 8 biological marker, alkane; anthropogenic source; bacterium; biomarker; catchment; climate change; dust storm; eolian deposit; freshwater sediment; lake pollution; pollen; saline lake; seasonality; sediment trap; snowmelt; soil microorganism; terrestrial deposit, article; chemistry; environmental monitoring; lake; microbiology; pollen; season; Turkey (republic); water pollutant, Biological Markers; Environmental Monitoring; Lakes; Pollen; Seasons; Soil Microbiology; Turkey; Water Pollutants, Chemical, Lake Van; Turkey, Embryophyta; Tracheophyta https://www.scopus.com/inward/record.uri?eid=2-s2.0-84865534666&doi=10.1007%2fs11356-012-0948-3&partnerID=40&md5=6ae90e779c93d816d2c6ab4f246aa602 cited By 8 C. Huguet S. Fietz N. Moraleda T. Litt G. Heumann M. Stockhecke F.S. Anselmetti M. Sturm article Tomonaga201299 In this work we present noble-gas concentration profiles measured in the water column and in the sediment pore water of the Earth's largest soda lake: Lake Van (eastern Anatolia, Turkey). The concentrations of noble gases (in particular Ar, Kr, and Xe) in the water body deviate significantly from the expected equilibrium concentrations calculated from the in situ temperature and salinity using existing solubility functions for seawater. The specific chemical composition of the water of the soda lake seems to be responsible for the observed deviations. Our measurements allow the identification and quantification of salinity factors that can be applied to correctly calculate the noble-gas equilibrium concentrations for the lake. These salinity factors provide a solid and robust empirical basis for the interpretation of noble-gas concentration signals measured in the sediment pore water of Lake Van in terms of palaeosalinity and palaeotemperature. © 2012 Elsevier Ltd. 2012 English 13679120 10.1016/j.jseaes.2012.05.011 Journal of Asian Earth Sciences 59 99-107 Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Water Resources and Drinking Water, Überlandstrasse 133, CH-8600 Dübendorf, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology (ETH), CH-8092 Zurich, Switzerland; Institute of Geochemistry and Petrology, Swiss Federal Institute of Technology (ETH), CH-8092 Zurich, Switzerland chemical composition; concentration (composition); empirical analysis; noble gas; paleoclimate; paleosalinity; paleotemperature; porewater; salinity; temperature; water column, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84867396520&doi=10.1016%2fj.jseaes.2012.05.011&partnerID=40&md5=20d49d6f5b6844b415729a2226868e8e cited By 20 Y. Tomonaga R. Blättler M.S. Brennwald R. Kipfer article Stockhecke2012148 The varved sediments of Lake Van provide a high-quality continental archive of seasonal to decadal-scale climate variability. In order to read the natural record, modern varve formation was studied on the basis of (1) remotely-sensed total suspended-matter (TSM rs) concentrations; (2) time-series of particle flux and water temperatures; and (3) turbidity, temperature, and oxygen profiles. TSM rs, validated by contemporaneous water-column sampling, shows great temporal and lateral variations (whitings and turbidity plumes). From 2006 to 2009, sequential sediment traps recorded high particle fluxes during spring and fall, medium fluxes during summer, and almost zero flux during winter. The mean total mass flux of 403mgm -2day -1 comprised 33% (seasonally up to 67%) calcium carbonate, 7% aquatic organic matter, 6% biogenic opal, and 54% detrital minerals. The CaCO 3 fluxes are controlled by river discharge (precipitation and snowmelt) during spring, by high productivity during summer, and by river discharge (precipitation before snowfall starts) and mixing during fall. In November 2007, an anomalously high CaCO 3 flux occurred as a result of a warm water surface supersaturated with calcite coinciding with an anomalous runoff event. The results demonstrate that the couplets of light and dark laminae in the short sediment cores are true varves representing spring-summer-fall and winter conditions, respectively. Consequently, varve formation can be linked to the seasonal climate pattern, providing a calibration that can be used to interpret the partially varved paleo-record of Lake Van and related environmental processes. © 2012 Elsevier B.V. 2012 English 00310182 10.1016/j.palaeo.2012.03.022 Palaeogeography, Palaeoclimatology, Palaeoecology 333-334 148-159 Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Surface Waters Research and Management, Ueberlandstrasse 133, P. O. Box 611, 8600 Dübendorf, Switzerland; Yüzüncü Yil Üniversitesi, Mühendislik-Mimarlik Fakültesi, Jeoloji Mühendisliǧi Bölumu 65080, Van, Turkey; Remote Sensing Laboratories, Department of Geography, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland calcium carbonate; concentration (composition); continental shelf; decadal variation; lacustrine deposit; oxygen; paleoenvironment; precipitation (climatology); remote sensing; river discharge; runoff; satellite data; sediment chemistry; sediment core; sediment trap; snowmelt; suspended particulate matter; time series; turbidity; water column; water temperature, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84860457518&doi=10.1016%2fj.palaeo.2012.03.022&partnerID=40&md5=459da20e04d0697ef86c933cb4c6c66d cited By 46 M. Stockhecke F.S. Anselmetti A.F. Meydan D. Odermatt M. Sturm article Litt2011477 Sedimentary archives host a wealth of information that can be used to reconstruct paleoclimate as well as the tectonic and volcanic histories of specific regions. Long and continuous archives from the oceans have been collected in thousands of locations by scientific ocean drilling programs over the past 40 years. In contrast, suitable continental archives are rare because terrestrial environments are generally nondepositional and/or subject to erosion. Lake sediments provide ideal drilling targets to overcome this limitation if suitable lakes at key locations have existed continuously for a long time. 2011 English 00963941 10.1029/2011EO510002 Eos 92 477-479 Steinmann Institute of Geology, Mineralogy and Paleontology, Bonn University, Bonn, Germany; Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Department of Geological Engineering, Eastern Mediterranean Centre for Oceanography and Limnology, Istanbul Technical University, Istanbul, Turkey; Helmholtz-Zentrum für Ozeanforschung Kiel, Forschungszentrum für Marine Geowissenschaften, Kiel, Germany 51 lacustrine deposit; marine sediment; Ocean Drilling Program; paleoclimate; reconstruction, Anatolia; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-84855316074&doi=10.1029%2f2011EO510002&partnerID=40&md5=7641bec8685ebfcfa0ad6af9da3ea566 cited By 30 T. Litt F.S. Anselmetti M.N. Çağatay R. Kipfer S. Krastel H.-U. Schmincke M. Sturm article Huguet20111289 The endorheic Lake Van in eastern Anatolia (Turkey) is the world's largest soda lake and it is an important site in paleoclimate studies to understand past continental conditions in western Asia. In order to gain further insights into the biomarker signatures in Lake Van's sediments we have analyzed particulate material in sediment traps deployed between August 2006 and July 2007. The biomarkers used were long chain alkenones (LCAs C37-C39, haptophyte lipids), isoprenoid glycerol dialkyl glycerol tetraethers (GDGTs, Archaea membrane lipids) and pigments (chlorins and fucoxanthin). The biomarker fluxes indicate a strong seasonality in export primary productivity and the phytoplankton community structure. The highest total mass and organic carbon fluxes were found in summer, coupled to strong stratification while the lowest mass fluxes occurred in winter at the time of water column mixing. With increasing temperatures in early spring, phytoplankton export productivity grew, coupled with an increase of total mass flux and organic carbon, which might be associated to enhanced nutrient input from snowmelt runoff. The percentage of C37:4 shows some correspondence with observed seasonal changes in Lake Van's stratification structure. We also evaluated the potential applicability of molecular temperature proxies derived from Archaea and haptophyte lipids. The use of the TEX86 proxy was precluded by low GDGT abundances. Estimated LCA temperatures were consistent with temperatures in the photic zone but no seasonality changes were observed despite the wide annual temperature range measured at Lake Van. © 2011 Elsevier Ltd. 2011 English 01466380 10.1016/j.orggeochem.2011.09.007 Organic Geochemistry 42 1289-1298 Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Surface Water Research and Management, Ueberlandstrasse 133, 8600 Dubendorf, Switzerland; Department of Geography, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; ICREA, Passeig Lluís Companys 23, 08010 Barcelona, Catalonia, Spain 11 Archaea; Biomarker flux; Chlorins; Eastern Anatolia; Fucoxanthin; Isoprenoids; Long chain alkenones; Membrane lipids; Organic carbon fluxes; Paleoclimate studies; Particulate materials; Photic zone; Phytoplankton community; Primary productivity; Seasonal changes; Seasonality; Snowmelt runoff; Soda lakes; Strong stratification; Temperature proxy; Temperature range; Total mass; Total mass flux; Water columns, Algae control; Anoxic sediments; Biomarkers; Glycerol; Lipids; Microorganisms; Organic carbon; Phytoplankton; Productivity; Sedimentology, Lakes, biomarker; community structure; isoprenoid; nutrient; organic carbon; paleoclimate; particulate matter; photic zone; phytoplankton; pigment; prokaryote; runoff; seasonality; sediment trap; snowmelt; stratification; temperature profile; water column, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-80855143724&doi=10.1016%2fj.orggeochem.2011.09.007&partnerID=40&md5=f768a0333e9183974a6ca44bb93efa87 cited By 23 C. Huguet S. Fietz M. Stockhecke M. Sturm F.S. Anselmetti A. Rosell-Melé article Tomonaga20112848 In this study, the largest ever carried out to measure noble gases in the pore water of unconsolidated sediments in lakes, the emission of terrigenic He through the sediment column of Lake Van was successfully mapped on the local scale. The main input of He to the water body occurs at the borders of a deep basin within the lake, which is probably the remains of a collapsed caldera. The 3He/4He ratio identifies the He injected into the sedimentary column of Lake Van as a mixture of He released from a mantle source and radiogenic He of crustal origin (3He/4He~2.6-4.1×10-6). During passage through the pore space, terrigenic He seems to be further enriched in radiogenic He that is most likely produced in the sediment column. In fact, two distinct trends in isotopic composition can be distinguished in the He injected from the lake basement into the sediments. One of these characterizes samples from the shallow water, the other characterizes samples from the deep basin. However, both of these trends are related to the same source of terrigenic He. The He fluxes determined seem to be characteristic of each sampling location and might be considered as a proxy for the fluid permeability of the deep sediment column. These new findings provide insight into the process of fluid transport within the sediments and into the process of formation of the lake basin. Moreover, the isotopic signature of the He that emanates into the water column of Lake Van is strongly affected by the mixing conditions prevailing in the overlying water body. This fact misled previous studies to interpret the terrigenic He in Lake Van as being solely of mantle origin (3He/4He~10-5). © 2011 Elsevier Ltd. 2011 English 00167037 10.1016/j.gca.2011.02.038 Geochimica et Cosmochimica Acta 75 2848-2864 Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Dübendorf, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology (ETH), CH-8092 Zurich, Switzerland; Institute of Geochemistry and Mineral Resources, Swiss Federal Institute of Technology (ETH), CH-8092 Zurich, Switzerland 10 basin evolution; deep-sea sediment; helium; isotopic composition; lacustrine deposit; lake water; mantle source; noble gas; permeability; porewater; sediment chemistry; sedimentary structure; spatial distribution, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-79955089402&doi=10.1016%2fj.gca.2011.02.038&partnerID=40&md5=702d9816c76729c35b61ebd10b6a5793 cited By 26 Y. Tomonaga M.S. Brennwald R. Kipfer article Kaden2010 Changes in the hydrological regime of the saline closed basin Lake Van, a large, deep lake in eastern Turkey, resulted in a lake level increase by about 2 m between 1988 and 1995, followed by a 1.5 m decrease until 2003 and a relatively constant lake level thereafter. Based on measurements of transient tracers (sulfur hexafluoride, CFC-12, 3H, 3He, 4He, Ne), dissolved oxygen, light transmission, conductivity- temperature-depth profiles, and thermistor data, we investigate the implications associated with lake level fluctuations for deep-water renewal and oxygenation. Our data suggest that deep-water renewal was significantly reduced in Lake Van between 1990 and 2005. This change in mixing conditions resulted in the formation of a more than 100 m thick anoxic deep-water body below 325 m depth. Apparently, the freshwater inflows responsible for the lake level rise between 1988 and 1995 decreased the salinity of the surface water sufficiently that the generation of density plumes during winter cooling was substantially reduced compared to that in the years before the lake level rise. Significant renewal and oxygenation of the deep water did not occur until at least 2005, although by 2003 the lake level was back to almost the same level as in 1988. This study suggests that short-term changes in the hydrological regime, resulting in lake level changes of a couple of meters, can lead to significant and long-lasting changes in deep-water renewal and oxic conditions in deep saline lakes. Copyright © 2010 by the American Geophysical Union. 2010 English 00431397 10.1029/2009WR008555 Water Resources Research 46 Department of Environmental Physics, Limnological Institute, University of Konstanz, Mainaustr. 252, D-78464 Konstanz, Germany; Department of Environmental Science, University of Koblenz-Landau, Fortstr. 7, D-76829 Landau, Germany; Department of Water Resources and Drinking Water, Swiss Federal Institute for Environmental Science and Technology (EAWAG), Überlandstr. 133, CH-8600 Dübendorf, Switzerland; Department of Isotope Geochemistry and Mineral Resources, Swiss Federal Institute of Technology, Zürich, Switzerland; Department of Anthropology, Yüzuncü Yil University, Zeve Campus, 65080 Van, Turkey 11 Conductivity temperature depths; Deep-water renewals; Deepwater; Eastern Turkey; Freshwater inflow; Hydrological regime; Lake level fluctuations; Lake levels; Long lasting; Mixing conditions; Oxic conditions; Saline lake; Transient tracers; Winter cooling, Biochemical oxygen demand; Dissolved oxygen; Light transmission; Neon; Oxygenation; Oxygenators; Pumps; Saline water; Sulfur; Sulfur hexafluoride, Lakes, deep water; dissolved oxygen; freshwater input; hydrological regime; inflow; lake level; oxic conditions; oxygenation; saline lake; salinity; surface water; tracer, Lake Van; Turkey https://www.scopus.com/inward/record.uri?eid=2-s2.0-78249269826&doi=10.1029%2f2009WR008555&partnerID=40&md5=f25ae4fbac03ebd760cce52c548ed2e2 cited By 48 H. Kaden F. Peeters A. Lorke R. Kipfer Y. Tomonaga M. Karabiyikoglu article Litt20091555 Lake Van is the fourth largest terminal lake in the world (volume 607 km3, area 3570 km2, maximum depth 460 m), extending for 130 km WSW-ENE on the Eastern Anatolian High Plateau, Turkey. The sedimentary record of Lake Van, partly laminated, has the potential to obtain a long and continuous continental sequence that covers several glacial-interglacial cycles (ca 500 kyr). Therefore, Lake Van is a key site within the International Continental Scientific Drilling Program (ICDP) for the investigation of the Quaternary climate evolution in the Near East ('PALEOVAN'). As preparation for an ICDP drilling campaign, a site survey was carried out during the past years. We collected 50 seismic profiles with a total length of ∼850 km to identify continuous undisturbed sedimentary sequences for potential ICDP locations. Based on the seismic results, we cored 10 different locations to water depths of up to 420 m. Multidisciplinary scientific work at positions of a proposed ICDP drill site included measurements of magnetic susceptibility, physical properties, stable isotopes, XRF scans, and pollen and spores. This core extends back to the Last Glacial Maximum (LGM), a more extended record than all the other Lake Van cores obtained to date. Both coring and seismic data do not show any indication that the deepest part of the lake (Tatvan Basin, Ahlat Ridge) was dry or almost dry during past times. These results show potential for obtaining a continuous undisturbed, long continental palaeoclimate record. In addition, this paper discusses the potential of 'PALEOVAN' to establish new results on the dynamics of lake level fluctuations, noble gas concentration in pore water of the lake sediment, history of volcanism and volcanic activities based on tephrostratigraphy, and paleoseismic and earthquake activities. © 2009 Elsevier Ltd. All rights reserved. 2009 English 02773791 10.1016/j.quascirev.2009.03.002 Quaternary Science Reviews 28 1555-1567 Steinmann Institute of Geology, Mineralogy and Palaeontology, University of Bonn, Nussallee 8, 53115 Bonn, Germany; Leibniz Institute of Marine Sciences (IFM-GEOMAR), Wischhofstr. 1-3, 24148 Kiel, Germany; Swiss Federal Institute of Aquatic Science and Technology (Eawag), Ueberlandstr. 133, 8600 Dübendorf, Switzerland; Department of Geology, University of Yüzüncü Yil, Zeve Campus, 65080 Van, Turkey; Istanbul Technical University, Geology Department, Maslak, 34469 Istanbul, Turkey; Alfred Wegner Institute for Polar and Marine Research, PO-Box 120161, 27515 Bremerhaven, Germany 15-16 Drill sites; Earthquake activity; Glacial-interglacial cycles; Lake level fluctuations; Lake sediments; Last Glacial Maximum; New results; Noble gas; Palaeoclimate; Pore waters; Quaternary climate; Scientific drilling; Sedimentary records; Sedimentary sequence; Seismic data; Seismic profiles; Site surveys; Stable isotopes; Tephrostratigraphy; Terminal lakes; Total length; Volcanic activities; Water depth, Arctic engineering; Drilling; Engineering geology; Glacial geology; Inert gases; Magnetic susceptibility; Sedimentology; Seismic waves; Seismology; Surveys; Water, Lakes, climate change; concentration (composition); drilling; geological record; glacial-interglacial cycle; Last Glacial Maximum; noble gas; paleoclimate; paleoseismicity; porewater; research program; seismic property, Eurasia; Lake Van; Turkey, Bacteria (microorganisms) https://www.scopus.com/inward/record.uri?eid=2-s2.0-67349229533&doi=10.1016%2fj.quascirev.2009.03.002&partnerID=40&md5=85dd867c734ba24607b4b3445acd8f2e cited By 165 T. Litt S. Krastel M. Sturm R. Kipfer S. Orcen G. Heumann S.O. Franz U.B. Ülgen article Reimer2009195 Saline, 450-m-deep Lake Van (Eastern Anatolia, Turkey) is, with 576 km3, the third largest closed lake on Earth and its largest soda lake. In 1989 and 1990, we investigated the hydrochemistry of the lake's water column and of the tributary rivers. We also cored the Postglacial sediment column at various water depths. The sediment is varved throughout, allowing precise dating back to ca. 15 ka BP. Furthermore, lake terrace sediments provided a 606-year-long floating chronology of the Glacial high-stand of the lake dating to 21 cal. ka BP. The sediments were investigated for their general mineralogical composition, important geochemical parameters, and pore water chemistry as well. These data allow reconstructing the history of the lake level that has seen several regressions and transgressions since the high-stand at the end of the Last Glacial Maximum. Today, the lake is very alkaline, highly supersaturated with Ca-carbonate and has a salt content of about 22 g kg-1. In summer, the warmer epilimnion is diluted with river water and forms a stable surface layer. Depth of winter mixing differs from year to year but during time of investigation the lake was oxygenated down to its bottom. In general, the lake is characterized by an Na-CO3-Cl-(SO4)-chemistry that evolved from the continuous loss of calcium as carbonate and magnesium in the form of Mg-silica-rich mineral phases. The Mg cycle is closely related to that of silica which in turn is governed by the production and dissolution of diatoms as the dominant phytoplankton species in Lake Van. In addition to Ca and Mg, a mass balance approach based on the recent lake chemistry and river influx suggests a fractional loss of potassium, sodium, sulfur, and carbon in comparison to chloride in the compositional history of Lake Van. Within the last 3 ka, minor lake level changes seem to control the frequency of deep water renewal, the depth of stratification, and the redox state of the hypolimnion. Former major regressions are marked by Mg-carbonate occurrences in the otherwise Ca-carbonate dominated sediment record. Pore water data suggest that, subsequent to the major regression culminating at 10.7 ka BP, a brine layer formed in the deep basin that existed for about 7 ka. Final overturn of the lake, triggered by the last major regression starting at about 3.5 ka BP, may partly account for the relative depletion in sulfur and carbon due to rapid loss of accumulated gases. An even stronger desiccation phase is proposed for the time span between about 20 and 15 ka BP following the LGM, during which major salts could have been lost by precipitation of Na-carbonates and Na-sulfates. © The Author(s) 2008. 2009 English 13806165 10.1007/s10498-008-9049-9 Aquatic Geochemistry 15 195-222 Geowissenschaftliches Zentrum der Universität Göttingen, Goldschmidtstraße 3, 37077 Göttingen, Germany; Technische Universität Darmstadt, Institut für Angewandte Geowissenschaften, Schnittspahnstr. 9, Darmstadt 64287, Germany 1-2 desiccation; dissolution; Holocene; hydrochemistry; hydrogeochemistry; lake level; paleolimnology; porewater; water column; water depth, Eurasia; Lake Van; Turkey, Bacillariophyta https://www.scopus.com/inward/record.uri?eid=2-s2.0-64249140015&doi=10.1007%2fs10498-008-9049-9&partnerID=40&md5=e6fd8206d7484feee3f6594ce74d4c6a cited By 106 A. Reimer G. Landmann S. Kempe article Litt200740 2007 English 18168957 10.2204/iodp.sd.4.13.2007 Scientific Drilling 40-41 Institute of Paleontology, University of Bonn, Nussallee 8, 53115 Bonn, Germany; Faculty of Geosciences, University of Bremen, Klagenfurter Straße, 28359 Bremen, Germany; Department of Geology, Yuzunou Yl Universitesi, Zeve Kampusu, 65080 Van, Turkey; Department of Anthropology, Yuzuncu Yl Universitesi, Zeve Kampusu, 65080 Van, Turkey 4 https://www.scopus.com/inward/record.uri?eid=2-s2.0-67349120599&doi=10.2204%2fiodp.sd.4.13.2007&partnerID=40&md5=974d8192a37fbea2910751d8e4247a03 cited By 6 T. Litt S. Krastel S. Orcen M. Karabiyikoglu