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Sabkhas are key landforms along the southern coast of the Arabian Gulf and represent modern analogues for depositional and diagenetic processes controlling properties and quality of ancient hydrocarbon‐bearing carbonates. While previous investigations of coastal sabkhas in Qatar have mainly focused on dolomitization processes, presented here is one of the first studies reconstructing facies changes and coastal formation in great detail. In the sabkha of Al‐Kharayej (Gulf of Salwa), fifteen different facies types were distinguished based on twelve sediment cores, two trenches, as well as grain‐size distribution, X‐ray powder diffraction, thin section and microfossil analyses. Age estimates were based on seventy‐eight 14C‐AMS and optically stimulated luminescence data. The sabkha parasequence comprises pre‐transgressive dune sands, a thin, transgressive layer of reworked dune material, a mid‐energy open‐coast to open‐lagoon facies, a low‐energy lagoon facies, saline lake facies (salina: swallow‐tail gypsum and gypsum mush) and the supratidal sabkha characterized by diagenetic overprinting (buckled gypsum crusts and halite crust). Transgressive marine flooding created open‐coast to open‐lagoon sedimentation after ca 7000 cal yr bp, followed by initial spit formation at the northern sabkha end at the beginning of the relative sea‐level highstand (6000 cal yr bp). This main outer spit prograded southward and a more narrow, low‐energy spit, diverted landward, closing a small lagoon in the northern sabkha 4500 to 4000 cal yr bp. The falling relative sea‐level and longshore drift intensified the southward extension and widening of the main spit, and the main lagoon became more shallow. At 2000 to 1500 cal yr bp, the outer spit had almost closed the main lagoon, leading to salina and, finally, sabkha conditions. It is shown how specific local conditions (coastline orientation; wind, wave, tidal energy, longshore drift; depositional relief; sediment sources) created a spit‐controlled sabkha that is genetically distinct from the classical model of shore‐perpendicular accumulation of coarser sediment during high tides or storms., Universität zu Köln, ExxonMobil Research Qatar, Ruprecht Karls Universitaet Heidelberg

International audience; Pendant les trois derniers millénaires, Ainos (moderne Enez, dans la province turqued’Edirne, en Europe) a été un des carrefours commerciaux de la Méditerranée orientale, entrel’Asie Mineure, l’Europe du Sud et les Balkans. Située sur une île qui est définitivementdevenue, au Néolithique, une presqu’île, entre les embouchures du fleuve Hèbre (en turcMeriç) et la mer Égée, Ainos/Enez a contrôlé tout le trafic Ouest-Est le long de la côteégéenne, mais aussi Nord-Sud, le long de la vallée du fleuve et de ses affluents. À l’époqueantique et médiévale, le delta de l’Hèbre n’avait pas encore atteint la ville elle-même, qui étaitentourée par la mer. Des bancs de sable ont progressivement fermé les golfes autour de lapresqu’île, donnant naissance à des lagunes propices à l’installation des ports, des salines etdes pêcheries. Cette importance stratégique d’Ainos est confirmée par les auteurs anciens etmodernes, mais aussi par les découvertes archéologiques extrêmement riches, surtout dans lesnécropoles fouillées par Sait Başaran autour de la ville.Dans cet exposé, nous évoquerons l’histoire d’Ainos, reconstituée à partir de sourceslittéraires confrontées à la documentation archéologique et géoarchéologique. Dans lapremière partie, nous nous concentrons sur l’espace urbain (l’« Acropole » et l’espace habitéautour), depuis le VI e siècle av. J.-C. à l’époque ottomane. Dans la seconde partie, nousprésentons les espaces frontaliers : les fortifications et quelques découvertes des nécropoles,actuellement à l’étude au Musée d’Edirne. Dans la dernière partie, nous synthétisons nosrésultats sur les ports urbains et extra-urbains, et sur les routes reliant Ainos (et Gala Gölü) aureste du monde.

Νησί των Νεολιθικών χρόνων, χερσόνησος από την Εποχή του Χαλκού, η πόλη του Αίνουυπήρξε ένα από τα κύρια εμπορικά σταυροδρόμια του Βορείου Αιγαίου, στις εκβολές τουΈβρου, μεταξύ της ελληνικής θάλασσας και της θρακικής ενδοχώρας. Οι ετήσιες τουρκικέςαρχαιολογικές ανασκαφές (ξεκίνησαν το 1973, υπό τη διεύθυνση του Sait Başaran για σχεδόν40 χρόνια, έως το 2019) έχουν αποκαλύψει αρκετά στοιχεία της χώρας (νεκροπόλεις, δρόμοι,οχυρώσεις). Η γεωαρχαιολογική έρευνα, που ξεκίνησε από τους Helmut Brückner, WolfgangRabbel και Thomas Schmidts στο 2011-2012, συνεχίστηκε τώρα στο πλαίσιο μιας γαλλικήςδιεθνούς αποστολής που συντονίστηκε από την Anca Dan, παρήγαγε δεδομένα για τη θέσηκαι την χρονολογίαν των λιμανιών της πόλης και για τις περιβαλλοντικές αλλαγές στηνεπικράτεια. Σε αυτή την εργασία, θα παρουσιάσουμε τα κύρια αποτελέσματα των κοινών μαςέργων σχετικά με τη φυσική εξέλιξη του ακρωτηρίου του Αίνου και του δέλτα του Έβρου,καθώς και για τις ανθρώπινες επιπτώσεις στην περιοχή., Island in Neolithic times, peninsula from the Bronze Age onwards, Ainos has been one of themain hubs of the Northern Aegean, at the mouth of the Hebros, between the Greek sea and theThracian hinterland. Annual Turkish archaeological excavations and surveys (started in 1973,directed by Sait Bașaran for nearly 40 years, until 2019) have revealed several components ofthe chora (necropoleis, roads, fortifications). The geoarchaeological research, initiated byHelmut Brückner, Wolfgang Rabbel and Thomas Schmidts in 2011-2012, now continued inthe frame of a French international mission coordinated by Anca Dan, produced data for thelocation and evolution of the city’s lagoonal harbours as well as for the environmentalchanges in the territory. In this paper, we will present the main results of our joint projectsabout the natural evolution of the Ainos promontory and Hebros delta, as well as about thehuman impact in the region.

Mesopotamia, known as the cradle of civilisation, gave rise to the first state-based urban societies with sophistic political hierarchies. Its rich history full of important cultural achievements was accompanied by fundamental environmental changes over the Holocene. While geo-bio-archives from the broader region reflect slightly varying climate histories, there is a clear consensus on a more humid climate regime during the Early Holocene, triggering early rain-fed agricultural practices in Northern Mesopotamia representing the foundation of initial urbanisation. In the southern basin, declining rainfall and higher competition for natural resources at a somewhat later stage in combination with the development of irrigation techniques and the transgression of the Arabian Gulf seem to have contributed to the formation of complex state-based urban societies at sites such as Eridu, Ur, and Uruk, where landscape dynamics are well-preserved in the stratigraphic record. Against the background of long-term climate trends, it seems that also Rapid Climate Change events—short-term climatic anomalies such as identified around 8,200, 5,200, or 4,200 BP—have taken their toll on Mesopotamian people. Many links between changes in climate and landscape, and socio-technical adaptation based on interdisciplinary research seem straightforward, especially where confirmation exists by cuneiform texts or archaeological evidence. The gap in chronological resolution between rather precise information on historical state development on the one hand, and on climatic changes with a much higher uncertainty on the other hand, may generate an elusive fit between records and requires caution in any attempt of environmental determinism when trying to explain cultural history.

International audience; The archaeological research started in Ainos in 1971-1972, under the direction of Arfif Erzen;it continued during 1978-1993, with the participation of Sait Bașaran, who directed theresearch from 1994 until 2019. During these decades, Ainos transformed itself from a simpletoponym, known from some ancient literary and epigraphic texts, published from the 19 thcentury onwards, to one of the best known archaeological sites in European Turkey. Thenearby Hoça Keșme, discovered by Sait Bașaran and his family and excavated by MehmetÖzdoğan, is now the most important Neolithic site in SE Europe. Ainos’ Greek, Roman andEarly Byzantine funerary zones (the so-called Çakıllık, the Su Terazisi and the Taşaltınecropoleis), excavated in very difficult conditions, due to the rising water table, have filledtwo rooms with exceptional finds in the Edirne Museum. Enez’s Kale (“Acropolis”) revealedthe traces of the oldest Greek habitation and is now open to the public, with a fully restored“Fatih” or “Hagia Sophia” Mosque.Sait Bașaran put Ainos on the map of the studies on Thrace, publishing or co-publishingnearly all the important historical and archaeological studies about this area. He opened hisexcavation to international and interdisciplinary projects, supported by the DeutscheForschungsgemeinschaft (SPP Häfen; 2012-2017) and by the French National ResearchFoundation and the French Ministry of Foreign Affairs (Mission d’Ainos; 2017-2021), whichmade significant progress in identifying Ainos’ topography, in particular the harbours andtheir chronology, from Greek Antiquity to late Ottoman times. Geoelectric profiles combinedwith geomagnetic and georadar surveys gave hints for the shape of two ancient harbourbasins, besides several other anchoring points. The sediment cores in the basins as well as onformer beaches show the evolution of the ancient maritime gulf south of Ainos into the Taşaltıand Dalyan lagoons. Through geochemical analyses, combined with the study of pollen andmicrofauna, our team was able to reconstruct the ecological history of these lagoons, and toidentify and date the human actions which transformed them first into harbours and later intosimple fishing basins.In this paper, we present a survey of the most important archaeological and geoarchaeologicalfinds and hypotheses concerning Ainos: after a general presentation of the historical andarchaeological data about the city (with a particular focus on the Roman time), we try toreconstruct the city’s connectivity, by discussing the Roman roads and harbour evidence,including the preliminary results of the 2021 campaign.

Controlled solely by the Earth's core, Earth's Magnetic Field reverses its polarity aperiodically on time scales of 104 to 106 years. This process is recorded by magmatic rocks and by sediments of a wide range of depositional environments, providing a Magnetic Polarity Stratigraphy (MPS). In combination with climate sensitive magnetic and sedimentological parameters, MPS forms the backbone of Neogene magnetic time scales yielding a temporal resolution of c. 104 years.Here, we combine for the first time the methodologically independent approaches of MPS with cosmogenic depth profile and burial isochron dating in order to improve the chronology of the MTC of the Lower Moselle using up to date methods. Magnetic polarity data from terrace accumulations and their sandy-silty cover beds reveal clear polarity changes from reversed (old) to normal (young) accompanied by climate indicative magnetic and sedimentological characteristics. Taking into account relative terrace elevations and age constraints from cosmogenic dating, a chronostratigraphic assignment of the MTC to an age interval ranging from c. 1.3 to 0.78 Ma is proposed. This period is characterized by increasing uplift of the RM marking the end of the trough valley period and antedating the onset of the formation of the entrenched valleys. The palaeomagnetically dated increase in subsidence of the Upper Rhine Graben at about 1 to 1.2 Ma ago (Scheidt et al., 2015) coincides with the magnetic dating of the end of the trough valley period in the RM suggesting a common cause of a fundamental change in western European crustal stress fields.

Zwischen 2011 und 2021 umfasste das archäologische Projekt „Taman'“ unter der Leitung von Udo Schlotzhauer und Denis Zhuravlev auch einen bedeutenden geoarchäologischen Aspekt, gefördert von Hans-Joachim Gehrke, dem ehemaligen Direktor des Deutschen Archäologischen Instituts. Dank der Zusammenarbeit mit den Geomorphologen Helmut Brückner und Daniel Kelterbaum kam es zu völlig neuen Erkenntnissen, nicht nur für die Geowissenschaften, sondern auch für die Archäologie und Alte Geschichte. H. Brückner und D. Kelterbaum revolutionierten die gängige Meinung über die holozänen Meeresspiegelschwankungen des Schwarzen Meeres. Sie zeigten, dass die bis dahin postulierten Regressions-Transgressions-Zyklen – insbesondere die sog. Phanagoreische Regression zwischen etwa 800 und 200 v.Chr. – nicht stattgefunden haben und stattdessen der Meeresspiegel des Schwarzen Meeres während des Holozäns kontinuierlich gestiegen ist und nur lokal durch tektonische Prozesse beeinflusst wurde. Darüber hinaus belegen die Sedimente aus ihren Bohrungen auf der Taman'-Halbinsel die ehemalige Existenz eines Archipels aus vier Inseln westlich der Mündung des Kuban-Flusses seit der Bronzezeit. Durch den Abgleich zwischen geowissenschaftlichen sowie den reichen archäologischen Befunden mit alten und modernen Texten und Karten, die seit mehr als einem Jahrhundert von Ausgrabungen und Vermessungen gesammelt wurden, konnten wir ein kohärentes Szenario für die Identifizierung der meisten antiken und mittelalterlichen Orts- und Flussnamen erstellen sowie den historisch überlieferten mentalen Rahmen der Landschaftsbeschreibungen rekonstruieren. Daraus ergibt sich eine völlig neue Sicht auf die Entwicklung der Topographie der heutigen Taman'-Halbinsel. In diesem Beitrag erläutern wir beispielhaft die Folgen der neuen Erkenntnisse für die antike Stadt Kepoi und dem heutigen Ort Taman'. Wir zeigen, dass die archäologischen und historischen Zeugnisse mit der geographischen Rekonstruktion der Landschaft im Umfeld dieser milesischen Kolonie im asiatischen Teil des Kimmerischen Bosporus und dem modernen Ort Taman' vereinbar sind.

Studies on soil formation under hyperaridity have so far focussed on the hyperarid core of the desert. Although the coastal sector of the Atacama Desert receives much larger amounts of moisture due to the orographic blocking of fog by the Coastal Cordillera, neither the pedogenic processes nor the timescales on which the coastal soils formed have as yet been studied. We therefore assessed physical and chemical soil parameters across a chronosequence of a coastal alluvial fan at Paposo, which is composed of four morphostratigraphic units. From each surface generation, we sampled four shallow soil profiles and multiple boulders for exposure dating using in situ cosmogenic 10Be. The combined establishment of a pedostratigraphy and morphochronology allows us to indirectly assess rates of soil formation and to make use of a soil catena as an unprecedented palaeoenvironmental archive for the Atacama Desert. Physicochemical soil properties mostly exhibit monotonic relationships with increasing time since abandonment of the first fan surface in the early Late Pleistocene. Pedogenic processes and weathering result in a loamification reflected in the soil texture by continuous fining with age. In contrast to typical Aridisols, trends towards desalinization as well as complete decalcification become apparent. Moreover, spectrophotometric soil colour measurements as well as the content of pedogenic iron oxides indicate that rubification plays a major role in the pedogenesis under coastal hyperaridity. Significant effects of biotic activity become apparent in organic carbon and phosphorus contents. Eventually, the results provide strong indications for in situ formation of clay-sized particles and colloids.

s & presentations / EGU General Assembly 2022 EGU General Assembly 2022, EGU2022, Vienna, Austria, 23 May 2022 - 27 May 2022; Göttingen : Copernicus Gesellschaft mbH EGU22-7889, 2 Seiten (2022). doi:10.5194/egusphere-egu22-7889, Published by Copernicus Gesellschaft mbH, Göttingen