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This work was supported by the Scientific and Technological Research Council of Turkey (TUBITAK; project number: 113Y418 ) and the Turkish Academy of Sciences (TUBA). We would like to thank Mustafa Avcıoğlu, Çağlar Çakır, Emrah Özpolat, Hakan Kaya and Abdullah Akbaş for their assistance in the field studies. Graham Lee is thanked for his help in correcting the English text of the article. We are honoured to dedicate this study in loving memory of the great Turkish Geographer, Professor Oğuz Erol, who passed away on April 11, 2014. Climate changes determined the repeated connections between the Black Sea, Caspian Sea and Mediterranean Sea. The landlocked anoxic Black Sea basin was exposed to several transgressions throughout Quaternary by the Mediterranean Sea through the Straits of Istanbul (Bosphorus) and by the Caspian Sea through the Manych-Kerch spillway. Sedimentological records of these connections are limited mostly to the marine terrace deposits of Marine Isotope Stage (MIS) 5e while the pre-MIS 5e period remains uncertain due to a lack of robust facies and chronological data from deep-sea sedimentary sequences. Here we discuss the imprints of multiple Mediterranean transgressions during Middle Pleistocene in the Black Sea based on facies analysis and the optical age of coastal carbonate aeolianites. Contrary to today's hydro-climate of the Black Sea, the aeolianites bear witness to the transformation of the Black Sea into a warm inland sea during successive Mediterranean invasions. Prior to the onset of aeolian deposition, paleosols were formed on the Eocene-aged hardened sandy silts, suggesting strongly washed soil. This is evidenced by no calcium carbonate and a high Rb/Sr ratio, with quartz amounting to of 99.8%. According to our OSL ages, carbonates deposited on the shelf plain under higher temperature and increased evaporation conditions in MIS 15 and the later interglacial phases were transported to the coastal sand dunes during the transitional phases of MIS 15–14, MIS 13–12, MIS 11–10 and MIS 9–8. We suggest that the carbonate-rich and ooid-containing aeolianites were repeatedly formed in the multiple Mediterranean transgression stages, beginning with an increasingly severe dry phase following the Brunhes-Matuyama magnetic reversal. Türkiye Bilimsel ve Teknolojik Araştırma Kurumu (TÜBİTAK) Turkish Academy of Sciences (TUBA) Publisher's Version Q1 WOS:000971464700001

On the seaward northwest slopes of Mount Keldag, Hatay, the combination of an unconformably overlapping sequence of cemented gravels on a wave-cut platform, and a raised notch and irregular pits left by grazing molluscs on the walls of this notch, carved in an NE-trending high-angle fault plane, retain the record of raised braided stream gravels transformed into beachrock. From the OSL ages, this study reveals that deposition of this sequence occurred between 232.30 ± 31.62 and 214.01 ± 27.42 ka during the penultimate interglacial. The four distinct facies identified are massive matrix-supported conglomerate, massive to crudely stratified gravel, cross-stratified gravel, and clast-supported open-work gravel. Extending to the paleo-coastline during the MIS7 highstand, this sequence was cemented by carbonate and iron-oxide cements and records an uplift of around 0.1 mm/year up to the present.

A historical earthquake-related co-seismic deformation observed on beachrock beds along the southern shoreline of Lake Iznik is discussed as a new paleoseismic record for an 8th century AD earthquake in the Middle Strand of the North Anatolian Fault, NW Turkey. Electrical Resistivity Tomography (ERT) images beneath the beachrock surface allowed monitoring of the subsurface trace of a normal fault dipping north along a 100 m surface rupture. No strike-slip deformation exists along the rupture, suggesting that the deformation in the beachrock is connected with a secondary structure, and that the main surface rupture was under the lake waters. The deformed beds of the beachrock, dated using Optically Stimulated Luminescence (OSL) to 1.3 ± 0.15 ka, are overlain by an undeformed secondary deposition of beds dated to 1.2 ± 0.09 ka. This allows us to narrow down the time of the faulting and implying that it was most likely a result of the AD 715 earthquake.

Approximately, 40% of Turkey’s landmass consists of soluble rocks (limestone, dolomite, and gypsum) highly suitable for karstification. While presenting different lithological composition, lithostratigraphic and structural characteristics, these rocks reach in some places up to 4000 m in elevation. Tectonic movements since the middle Miocene have played, together with climate, a major role in the processes of karst development. Several factors intervene in the formation processes and history of the karstic landscapes of Turkey: structural dynamics (mainly extensional tectonics and block faulting) and its spatial distribution, relief rejuvenation responding to the combination of uplift intensity and sea-level changes and the stratigraphic/lithologic context. Resulting from the various combinations possible, there are large-scale differences in the evolution of the karstic landscape within short distances. Consequently, six karstic regions and eleven distinct sub-karstic areas can be identified on the basis of their different morphogenetic and morphometric characteristics. © 2019, Springer Nature Switzerland AG.

The Lake Van Basin, located at the collision zone of the Eurasian and Arabian plates, has great potential in terms of geological heritage. The world's largest soda lake which gives its name to the basin contains magnificent geological structures. Lacustrine deposits of the lake represent important clues about seismic activity during the Late Quaternary in addition to its sedimentological and paleontological background. Seismites-deformational structures which are formed during earthquakes in unconsolidated sediments-are very rare geologic phenomena. These structures, formed by earthquakes of magnitude >= 5 under suitable conditions, provide valuable information about the responsible faults and their seismic repetition frequency for the region. Today, rising awareness of geological heritage is a glimmer of hope for the protection and preservation of these rare structures in the Lake Van Basin for the generations to come. Conservation of these structures will also help the protection of other naturally, historically, and culturally significant geological beauties. The responsibility for the promotion and conservation of these geological heritages should be a mission not only for the hosting country but also for the entire geological community.

This study examined the vertical distribution of heavy metals in core sediments taken from Lake Cildir, Turkey, and their potential ecological risks together with organic carbon content and chlorophyll degradation products. Samples were collected from six sampling stations determined along two main transections aligned in north–south and east–west directions. The enrichment (EF) and contamination factor (CF), potential ecological risk (PER) index, and pollution load index (PLI) were calculated from the obtained results. For the elements Pb, As, and Cd, a moderate level of contamination was detected, whereas a moderate-to-high concentration level was obtained for Mn. The highest contamination level was found for Hg. A pollutant accumulation exists particularly in the surface sediments. Cd and Hg are the only two metals considered to be a potential risk factor in the lake.

This paper provides the first general account of the facies associations that fill a Miocene fault bounded basin located in the central part of the Isparta Angle (Turkey), in order to define process-controlled sedimentary units reflecting environmental changes in a general tectonic and stratigraphic framework. The northern and western parts of the Koprucay Basin are occupied by extensive conglomeratic successions belonging to three distinct alluvial fan–fan delta systems (AFD), which pass laterally into pelagic mudstones in the deeper part of the basin. In spite of syn- and post-sedimentary tectonics, most of the sedimentary units still display their original relationships. This allows definition and interpretation of the conspicuous facies changes in the clastic successions according to their position along complete sections across the basin. The bulk of the paper is thus devoted to the description of 11 sub-facies types that have been identified in the three AFDs, and their environmental interpretation. As a result, the origin and sedimentary infill of the Koprucay Basin appears primarily controlled from Langhian to Tortonian by the N–S trending Kirkkavak Fault. After uplift and erosion of the western part of the basin, the final closure of the Isparta Angle resulted in a westward displacement of the Anatolian block during Upper Tortonian.

Climatic changes during the last climatic cycle have been studied using three sediment cores from the Konya plain, a now dry, closed and semi-arid lacustrine basin at 1000 m altitude in central Anatolia, Turkey. The reconstruction of regional climatic characteristics and evolution is based on mineral, diatom, pollen and molluscan content of sediments. Correlations are made between cores using 14C and U-Th ages, stratigraphy and drought levels shown by changes in mineral contents. Environmental responses to local and regional climatic changes are traced by trends in authigenic carbonates, evaporites, detrital mineral content and by diatom-inferred salinity levels. Our data have shown that, during the period covering the end of the previous Glacial (Termination II) and the last Interglacial (between c. 150 and 117 ka), peat and freshwater shallow lakes expanded. From 117 to 66 ka, the plain was occupied by lakes, the salinity and existence of which varied in time and space. Specific events are marked by mineralogic and stratigraphic signals at (i) c. 101 ka and (ii) 66 ka. From 66 ka to 30 ka, desiccation of the lake is marked by a hiatus. At c. 27 ka, milder climatic conditions led to the extension of freshwater marshes and lakes in the central depressions while palaeosols developed on the emerged parts of the plain. From 25 to 20·5 ka 14C cal., the sediments of a freshwater to brackish lake are present in one core only. From 20·5 ka 14C cal. onwards, strong evaporitic conditions occurred, the lake edges being transformed into playas. Upper parts of the sequences registered other lacustrine short phases, both before the Younger Dryas and during the Holocene. Copyright © 1999 John Wiley & Sons, Ltd.

Results presented here are part of a research programme to investigate the environmental evolution in central Anatolia during the Pleistocene. In this study, tephra are used as chronostratigraphical markers between lacustrine sequences studied in cores or in sections surrounding eruptive centres of the Central Anatolian Province. At different locations in the Konya Plain and Cappadocia, tephra have been identified, characterized and linked to eruptions of the nearby volcanoes. Seven different tephra have been clearly identified in lacustrine sequences of the Konya Plain. 14 C dates on shells or organic matter, as well as 230 Th / 234 U ages on gypsum, give a chronological framework to the tephra layers. In addition, the study of the sediment fill of the Eski Acigol maar near Nevsehir has allowed the recognition of several eruptions during Late Glacial and Holocene in the vicinity of Acigol. The results show the first tephra to be identified in lacustrine sequences of Anatolia; they also show the Cappadocian volcanism to be very young (≤35 ka). This young volcanism is often of a basaltic type and does not include thick differenciated pyroclastic deposits.

A tephrostratigraphy is proposed, based on the study of several Quaternary sequences in the upper basin of the river Melendiz, on the N-E slopes of the Hasan dag, a large strato-volcano in central Anatolia (Turkey). The sedimentary characteristics of the oldest formations, located on the edges of the Melendiz gorges, show an environment dominated by fluvial input (Belisirma) or by fluvio-lacustrine processes (Ihlara), previous to the pyroclastic activity occurring in the eastern part of the volcano (Kûçûk Hasan dag). This activity produced four groups of rhyodacitic pumice-ash falls, interrupted by colluvium deposits and palaeosol formation phases leading to the development of andosols. Afterwards, an important debris-avalanche coming from the N-W part of the strato-volcano filled the Melendiz gorges, before a pumice flow submerged its edges in the area of the Kitreli village (basin of the Güvercinlik, a tributary of the Melendiz). The westward displacement of the activity (andesitic flows and nuées ardentes of the Büyük Hasan Dag) allowed the renewal of the river incision and the shaping of the main present landscape features. Tephra and tephric deposits (reworked tephra) provide good tie-layers allowing correlations between various sequences, on the basis of the textural, mineralogical and geochemical characteristics of the pumices. They confirm the variety of stratigraphies and the existence of several hiatus in relation either to the geomorphological setting of the remaining deposits or to their distance from the volcano (proximal to distal areas). Unfortunately, it has not yet been possible to date clearly this significative succession. According to ¹⁴C dates, the Melendiz debris avalanche and the Kitreli pumice flow are aged end of the Upper Pleistocene ; older palaeosols have given C ages t 30 to 35000 yrs B.P. K-Ar dating performed on lavas from the Büyük Hasan dag summit gives results of 33 ± 2 and 29 ± 1 ka, thus confirming the importance of the activity of this volcano during Upper Pleistocene and probably during Holocene (a flow is K-Ar dated < 0)., L'étude de nombreuses séquences quaternaires du bassin supérieur de la Melendiz permet de proposer une téphrostratigraphie de la bordure N-E du Hasan dag, important strato-volcan d' Anatolie centrale (Turquie). Les premières formations, localisées en bordure des gorges de la Melendiz, caractérisent un régime sédimentaire à dominante fluviatile (Belisirma) ou fluvio-lacustre (Ihlara), puis l'activité pyroclastique se développe à Test du volcan (Petit Hasan dag). Elle engendre quatre groupes de retombées cendro-ponceuses rhyodacitiques, séparées par des phases de colluvionnement et de pédogenèse marquées par le développement d'andosols. Une importante avalanche de débris issue du N-W du strato-volcan, comble ensuite les gorges de la Melendiz, puis une coulée de ponces ennoye sa bordure aux environs de Kitreli (bassin-affluent de la Gûvercilink). Le déplacement de l'activité vers l'ouest (coulées et nuées ardentes andésitiques du Grand Hasan dag), permet une reprise de l'incision et le dégagement des modelés actuels du secteur. Les niveaux-repères fournis par les téphras ou leurs produits de remaniement autorisent une corrélation précise des séquences en fonction de la texture, de la minéralogie ou de la géochimie des ponces. Ils corroborent la variété des stratigraphies et la multiplicité des hiatus en fonction de la position géomorphologique des témoins ou de leur éloignement par rapport au strato-volcan (domaine proximal à distal). Cette succession caractéristique reste malheureusement mal datée. Les datations C semblent situer l'avalanche de débris de la Melendiz et la coulée de Kitreli vers la fin du Pléistocène supérieur ; les paléosols antérieurs, sont plus âgés que 33 000 ans. Les datations K-Ar de 33 ± 2 et 29 ± 1 ka, corroborent l'importance de l'activité du Grand Hasan dag durant le Pleistocene supérieur et sa continuation probable durant l'Holocène (âge calculé d'une coulée «< 0», soit «postérieur» au présent)., Pastre Jean François, Kuzucuoglu Catherine, Fontugne Michel, Guillou Hervé, Karabiyikoglu M., Ercan Tuncay, Türkecan Ahmet. Séquences volcanisées et corrélations téphrologiques au N-E du Hasan Dag (haut bassin de la Melendiz, Anatolie centrale, Turquie) [Volcanised sequences and tephrochronologic correlations in the area N-E of the Hasan Dag (upper basin of the river Melendiz, Central Anatolia, Turkey)]. In: Quaternaire, vol. 9, n°3, 1998. pp. 169-183.

Sedimentological and geomorphological studies of terraces around Lake Van (1647 m) provided a preliminary framework for lake-level variations. The elevations of terraces and past lake level were measured with a differential global positioning system. A chronology is developed using 234 U/ 230 Th dating of travertines, 39 Ar/ 40 Ar dating of pyroclastites and 14 C dating of organic matter. Facies and stratigraphic correlations identify four transgressions (C1 0 ,C 1 00 ,C 2 0 and C2 00 ), each followed by a regression which ended with low lake levels that caused river incision and terrace formation. Evidence of the oldest transgression (C1 0 ) is found in the uppermost reaches of valleys up to 1755 m, an altitude higher than the present lake threshold (1736 m). This C1 0 transgression may be related to pyroclastic flows which dammed an outlet located in the western part of the lake basin and which is dated to before 105 ka. After 100 ka, a second transgression (C1 00 ) reached 1730/1735 m, possibly related to a younger ignimbrite flow, in association with high water inflow (warm and/or wetter conditions). The two younger transgressions reached 1700-1705 m. The first one (C2 0 ) is dated to 26- 24.5 cal. ka BP and the second one (C2 00 ) to 21-20 cal. ka BP. Available data suggest that the long-term lake-level changes responded mainly to climate oscillations. Additional events such as river captures caused by volcanic falls filling valleys, tectonism, erosion and karstic diversion may have impacted these long-term lake-level changes. Copyright # 2010 John Wiley & Sons, Ltd.

Le lac de Van, dans les montagnes d’Anatolie orientale, ne possède pas d’exutoire naturel. Malgré son volume (604 km3), les amplitudes des variations de son niveau témoignent, depuis 1944, d’une sensibilité élevée aux fluctuations hydro-climatiques. Dans cette perspective, les dépôts hérités d’anciens hauts niveaux, conservés sous forme de terrasses côtières dans les parties aval anciennement immergées des affluents du lac, permettent d’identifier, de caractériser et de dater les changements de volume d’eau lacustre qu’ont enregistrés les sédiments qui sous-tendent ces terrasses. Plusieurs travaux récents sur les sédiments du fond du lac de Van ont mis en évidence leur intérêt exceptionnel pour la reconstitution des paléoclimats et permis de détailler l’évolution paléoenvironnementale du Tardiglaciaire et de l’Holocène. Cependant, les études des dépôts lacustres émergés restent rares. Ces dépôts font l’objet ici d’une étude géomorphologique de terrain couplée à des caractérisations sédimentologiques de faciès, des mesures altimétriques DGPS, des reconstitutions spatialisées et la mise en place des premiers jalons d’une chronostratigraphie basée sur des datations14C de dépôts organiques et coquilles, 39Ar/40Ar de tephras, et U-Th de travertins. Dans l’attente de datations OSL, nos résultats préliminaires permettent d’identifier au moins deux cycles de transgression, datés respectivement du début du dernier Glaciaire et d’une période couvrant le Dernier Maximum Glaciaire (DMG). Chaque cycle correspond à une phase de transgression rapide, suivie de variations intermédiaires d’amplitude plus ou moins forte, et se terminant par une longue phase de régression par paliers. La cause de ces variations et, notamment, la part qu’y a prise le climat est évidente pour le cycle datant du DMG, mais l’est moins pour celui marquant le début du Glaciaire dont les liens avec le volcanisme et la tectonique sont étroits. La forte instabilité de la paléogéographie est liée au volcanisme qui est à l’origine de barrages ayant entraîné la fermeture du bassin versant du lac. In the eastern Anatolian Mountains, the relatively high-magnitude variations exhibited by the level of Lake Van in recent years indicate, as the lake has no outlet, that this level can be considered as a sensitive indicator of climate if these variations respond to changes in water input/output. Until now, previous palaeoclimatic research has focused mainly on deep sediments in the lake, which provided an environmental sequence which is today a reference for the Late Glacial and the Holocene in the Middle East. In spite of many landforms and deposits around the lake pointing out to the occurrence of very high levels in the past, studies on the lacustrine sediments preserved in terrace records around the lake have remained quite rare since a frst exhaustive overview realized in the l970’s. We here present the frst results of a field work coupled with sedimentology studies (stratigraphy, facies analyses), DGPS elevation measurements, spatialized reconstructions. Chronostratigraphy takes advantage of the presence of interstratified tephras layers dated by 39Ar/40Ar, of travertines dated by U-Th series, as well as of organic deposits and shells dated by 14C. Results evidence the occurrence of two major and rapid transgressions, the first one happening at the beginning of the Last Glacial, the second one in the millennia preceding the Last Glacial Maximum (LGM). Each identified lacustrine cycle started with a very rapid transgression followed by slower regressions with intermediate oscillations. Regressions started immediately after the highest stand was reached (+80 m and +55 m). Regressions lasted long, with some stand-by during the descent, allowing erosion surfaces to truncate the surface of the emerging lake deposits. During Upper Pleistocene, tectonic and volcanic activities interfered with the climatic record of lake levels, both by deforming deposits locally (uplift, faulting) and by modifying the drainage area and river network of the lake basin (closure by damming, captures, isolation). Our preliminary results thus enlighten the complexity of the processes triggering the high magnitude transgressions of the Upper Pleistocene Van Lake, as well as the difficulty to establish correspondences between climatic changes and water volume changes as evidenced by past shoreline deposits preserved in the terrace sedimentary records.

Facies and environmental setting of the Miocene coral reefs in the Late Cenozoic Antalya Basin are studied to contribute towards a better understanding of the time and space relationships of the reef development and the associated basin fill evolution in a tectonically active basin. The Antalya Basin is an extention–compression-related late post-orogenic basin that developed unconformably on a basement comprising a Mesozoic para-authocthonous carbonate platform overthrust by the Antalya Nappes and Alanya Massif metamorphics within the Isparta angle. The Late Cenozoic basin fill consists of thick Miocene to Recent clastic-dominated terrestrial and marine deposits with subordinate marine carbonates and extensive travertines. Late Miocene compressional deformation has resulted into three parts, referred as Aksu, Koprucay and Manavgat sub-basins, bounded by north–south extending dextral Kirkkavak fault and the westward-verging Aksu thrust. Coralgal reefs are common within the Miocene sequences and are represented by coral assemblages closely similar to that of the circum-Mediterranean fauna. They occur as massive, small, isolated, patch reefs that developed in two contrasting depositional systems (progradational coastal alluvial fan and/or fan-delta conglomerates and transgressive shelf carbonates) during Early–Middle Miocene and Late Miocene. The Early–Middle Miocene reefs are represented by rich and high-diversity hermatypic corals, mainly comprising Tarbellastraea, Heliastraea, Favites, Favia, Acanthastraea, Porites, Caulastraea and Stylophora with occasional presence of solitary (ahermatypic) corals, Lithophyllia, Mussismilia and Leptomusso, locally reflecting relative changes in the bathymetry. Densely packed, massive, domal and hemispherical growth forms bounded by coralline algae and encrusting foraminifera Acervulina construct the reef framework. They occur in the fan-deltas and the transgressive open marine shelf carbonates of the Manavgat and the Koprucay sub-basins. The Late Miocene reefs occur only in the Aksu sub-basin and are characterized by low-diversity hermatypic corals exclusively dominated by Porites and Tarbelastraea with minor Siderastraea, Favites and Platygyra. They developed on alluvial fan/fan-delta complexes and shallow marine shelf carbonates. The Miocene coral reef growth and development in the Antalya Basin are characterized by large- to small-scale, transgressive–regressive reefal cycles which are closely related to the complex interaction of sporadic influxes of coarse terrigeneous clastics derived from the tectonically active basin margins and the related sea-level fluctuations.

This study presents results from a multi-proxy analysis of cores taken in a crater-lake sequence from Eski Acigöl in centr-al Turkey which cover the period from pre-c. 16000 cal. yr BP to the present. The sediments comprise an upper unit of enerally non-laminated, banded to massive silts and peats of mid- to late-Holocene age, overlying a laminated unit of late-Pleistocene to early/mid-Holocenie age. The laminae, comprising mainly aragonite. amorphous silica (diatom frustules) and organic matter were formed in a relatively deep, dilute. meromictic lake. Pollen data indicate an abrupt replacement of Arteyisia-chenopod steppe by grass-oak-terebinth parkland during the period of laminae deposition, marking the start of the Holocene. A gradual increase in tree pollen during the early Holocene came to an end c. 6500 cal. yr BP (U-series and adjusted 14C timescale), when mesic deciduots taxa declined at the same time as lake levels fell. Human impact on regional vegetation is inferred from a sharp decline in oak around 4500-4000 cal. yr BP. Diatom, isotopic and mineralogical data indicate that during the second half of the Holocene the lake became relatively shallow and oscillated between fresh and brackish/evaporated water conditions. The contrast between wetter early and drier late-Holocene climatic conditions is matched by other eastern and central Mediterranean proxy climate data. While the Eski Acigöl sequence resembles Holocene hydroclimatic changes in the Saharo-Arabian zone and was also apparenitly linlked to orbital forcing, it is unlikely to have had the samlle direct cause, i.e., an expansion and subsequent retreat of monsoon rainfall.

Several sand flats located on the northern shores of the Late Pleistocene palaeolake of the Konya plain (inner Anatolia, Turkey), are related to changes in lake levels. In this paper, the two main dune systems are mapped according to their geomorphological, sedimentological and dynamic characteristics, and their significance is discussed with regard to the environmental changes since the Late Pleistocene, both at time of the former lake and during the drier periods of the Holocene. Cross-sections show the relationship of the dunes to the topography of the basement. Analyses of the sand fraction show distinct characteristics in size distribution, quartz and shell contents, wind erosion effects on the quartz grains and petrographic composition. Interpretation of the results, coupled with information provided by the geomorphology of the dune systems studied in the field and from aerial photographs and satellite images, highlights the importance and variations in time of local factors such as prevailing winds, sand sources, changes in lake levels and vegetation. A chronology of the main sand fields is proposed, based on the evidence of three main droughts during the Upper Pleistocene. The older one, much eroded (maximum height=3 m), covers a limestone surface at +50 m above the bottom of the dried lake. An Optical Scanning Luminescence (OSL) date shows a last period of accumulation at 14,328±3220 years. The younger one (maximum height=12 m) has moved over the emerged Late Pleistocene lacustrine marls. An OSL date gives an age of 5674±988 years for the last accumulation period. Evidence of very recent activation of this younger dune system is apparent as a result of overgrazing and excessive land reclamation. A third period of dominant wind action and dune construction is responsible for the installation of a younger and thin dune field over the Mid-Holocene lacustrine deposits of the Karapinar lake. The success of the stabilization programme of the dunes over the last 30 years shows that the last period of dune movement is not related to climate change but to overpressure on the land due to the needs and activities of an increasing population.

The Karapinar playa occupies the floor of a lacustrine depression which was part of the Upper Pleistocene (23,000–17,000 yr BP) Konya palaeolake. Four sections opened in the floor of the Karapinar depression permit the study of the stratigraphy of Holocene sequences. From the sedimentological analyses of the sand content, organic carbon content, heavy mineral inputs and molluscan fauna, associated with the sediment observation (marks of aerial weathering and plant roots), several environmental changes can be assessed during Holocene. Underneath a characteristic black marshy layer, a thick sequence of lacustrine clay shows two episodes of cencentrated unbroken shells of Dreissena polymorpha, which is a typical species of the Upper Pleistocene open lacustrine environment in the area. Between these two episodes, stem marks in the clay show that the lake dried during an unknown period, during which soil was formedand carbonatic nodules occurred on its bottom. During Early to Mid-Holocene, the development of a marshy eutrophic environment is testified by an extensive organic and molluscan-rich layer situated in all the sections at about 1 m below the surface. 14C dates obtained both on organic matter and on shells from this marshy layer are mainly distributed between two periods: 13,800–13,400 BP and 6800–6500 BP. The latter period corresponds to the end of the occupation of the Neolithic site of Catal Huyuk in the Konya plain. Around 6500 BP, the marshes are replaced by a lake which left a 10–30 cm thick clay layer. This Mid-Holocene lacustrine readvance ended with a brutal drought marked by a change in sedimentation with a 30 to 60 cm thick silty and sandy aeolian deposit covering the lacustrine clay. The Late Holocene is marked by arid to semi-arid processes, with wind as an important geomorphic agent. During thi uncalib. 14C), we assume that it correspand to the arid to semi-arid dry period which followed the Mid-Holocene lacustrine stage.