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Yayın Dating fossil root cast (Black Sea coast, Turkey) using thermoluminescence: Implications for windblown drift of shelf carbonates during MIS 2(Elsevier Ltd., 2016-05-16) Polymeris, George S.; Kitis, George; Güneç Kıyak, Nafiye; Theodosoglou, Eleni; Tsirliganis, Nestor C.; Ertek, Topçu Ahmet; Erginal, Ahmet EvrenRhizoliths are mostly sub-aerially exposed root prints which appear through removal of the rock units that cap them. A horizontal-lying residual of a rhizolith, consisting purely of soft inner core material of white color was recovered 10 km west of Şile, Istanbul, in northwest Turkey within laminated oolithic massive aeolianite. The inner part, consisting purely of calcium carbonate, was dated by applying thermoluminescence, while for the outer shelves optically stimulated luminescence of quartz was used for age assessment. The age of the CaCO3 infill occupying the original place of the decayed plant roots was found to be 26.8 (±5.0) ka, corresponding to MIS 2. When compared with the ages of the middle (105.2 ± 15.6 ka) and outer (127 ± 9 ka) layers, corresponding to the later stage of MIS 5e or early stage of MIS 5d, the inner core coincides with the last glacial period when the sea-level was lower than the present, promoting transportation of ooids by offshore winds in conjunction with the exposed shelf carbonates. Based on the results yielded, rhizolith is much younger than the host rock aeolianite and witnesses to last glacial sea level lowstand when removal of shelf carbonates by offshore winds was promoted from the exposed shallow shelf plain. The results provide strong evidence that rhizoliths may not be coeval with the aeolianites within which they are embedded.Yayın Aeolian imprints of multiple Mediterranean invasions of the Black Sea during Pleistocene(Elsevier B.V., 2022-03-04) Erginal, Ahmet Evren; Güneç Kıyak, Nafiye; Makaroğlu, Özlem; Bozcu, Mustafa; Öztürk, Muhammed Zeynel; Selim, Haluk Hamit; Nowacyzk, Norbert R.; Kaya, Nurcan; Öztürk, Tuğba; Karabıyıkoğlu, Mustafa; Polymeris, Georgios S.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.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.Yayın Differential uplift along the northern margin of the Central Anatolian Plateau: inferences from marine terraces(Pergamon-Elsevier Science LTD, 2013-12-01) Yıldırım, Cengiz; Melnick, Daniel; Ballato, Paolo; Schildgen, Taylor F.; Echtler, Helmut P.; Erginal, Ahmet Evren; Güneç Kıyak, Nafiye; Strecker, ManfredEmerged marine terraces and paleoshorelines along plate margins are prominent geomorphic markers that can be used to quantify the rates and patterns of crustal deformation. The northern margin of the Central Anatolian Plateau has been interpreted as an actively deforming orogenic wedge between the North Anatolian Fault and the Black Sea. Here we use uplifted marine terraces across principal faults on the Sinop Peninsula at the central northern side of the Pontide orogenic wedge to unravel patterns of Quaternary faulting and orogenic wedge behavior. We leveled the present-day elevations of paleoshorelines and dated marine terrace deposits using optically stimulated luminescence (OSL) to determine coastal uplift. The elevations of the paleoshorelines vary between 4 +/- 0.2 and 67 +/- 1.4 m above sea level and OSL ages suggest terrace formation episodes during interglacial periods at ca 125, 190, 400 and 570 ka, corresponding to marine isotopic stages (MIS) 5e, 7a, 11 and 15. Mean apparent vertical displacement rates (without eustatic correction) deduced from these terraces range between 0.02 and 0.18 mm/a, with intermittent faster rates of up to 0.26 mm/a. We obtained higher rates at the eastern and southern parts of the peninsula, toward the hinterland, indicating non-uniform uplift across the different morphotectonic segments of the peninsula. Our data are consistent with active on- and offshore faulting across the Sinop Peninsula. When integrated with regional tectonic observations, the faulting pattern reflects shortening distributed over a broad region of the northern margin of the Central Anatolian Plateau during the Quaternary.
