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Yayın Optical stimulated luminescence dating study of eolianite on the Island of Bozcaada, Turkey: Preliminary results(The Coastal Education and Research Foundation, 2010-07) Güneç Kıyak, Nafiye; Erginal, Ahmet EvrenIn the present paper, eolianite exposed on the south coast of the semiarid island of Bozcaada, Turkey, was investigated on the basis of geomorphologic and petrographic data, and optically stimulated luminescence (OSL) dating results. The eolianite is lithic arenite in composition and contains abundant quartz, calcite, and various lithoclasts amalgamated with micritic calcite, sparitic calcite, and meniscus cements. Within the youngest layers standing at 1-2 m above sea level, the rock contains rhizoliths with or without carbonaceous fills. The OSL ages obtained ranged between 24.21 +/- 1.53 ka and 16.18 +/- 1.70 ka, suggesting that eolianite constitutes an example of low stand deposits coinciding with oxygen isotope stage 2 (OIS-2).Yayın Eolianite and coquinite as evidence of MIS 6 and 5, NW Black Sea coast, Turkey(Elsevier B.V., 2017-04) Erginal, Ahmet Evren; Güneç Kıyak, Nafiye; Selim, Hamit Haluk; Bozcu, Mustafa; Öztürk, Muhammed Zeynel; Ekinci, Yunus Levent; Demirci, Alper; Elmas, Elmas Kırcı; Öztürk, Tuğba; Çakır, Çağlar; Karabıyıkoğlu, MustafaThis paper discusses the implications of a lowstand carbonate eolianite and overlying transgressive sequence of coquinite at Şile on the Turkish Black Sea coast based on composition, depositional characteristics and optical age estimations. The cross-bedded eolianite is a mixed ooid quartz grainstone in composition, yielding a depositional age matching MIS 6. It formed at the backshore of the paleobeach with the supply of sediment the from the beach face and offering insights into the drift of mixed shallow marine carbonates and siliciclastics together with radial ooids by onshore winds from a subaerially exposed high- to low-energy ooid shoals and oolitic sand complexes which developed parallel to the shoreline on the shallow shelf margin. During this lowstand, a low-relief dune retaining a record of opposing paleowind directions than that of prevalent northeasterly winds of today appears to have been lithified to form dune rock (aeolinite) under drier conditions compared to the present. Coinciding with MIS 5e, shallow marine coquina beds resting unconformably on the eolianite indicate the occurrence of the Mediterranean transgression during the last interglacial, as confirmed by benthic foraminifera within the high-salinity tolerant coquina shells.
