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    Formation of Holocene paleosols in a relict sand dune sequence at Kıyıköy, Türkiye
    (Tubitak Scientific & Technological Research Council Turkey, 2025) Erginal, Ahmet Evren; Bozcu, Mustafa; Yakupoglu, Nurettin; Akbas, Abdullah; Kaya, Hakan; Tunc, Ismail Onur
    The paleoclimatic indicators from a relict dune and paleosol sequence observed south of K & imath;y & imath;k & ouml;y Port, NW T & uuml;rkiye, provide insights into the variable paleoclimatic conditions in the western Black Sea coastal zone over the last 4700 yrs BP. The relict dunepaleosol sequence consists of reddish-brown coarse sands with abundant shells and overlying paleosol. Radiocarbon dating of Donax trunculus shells collected from the lowest part of the relict dune revealed the onset of sand deposition 4689 +/- 123 yrs ago. The dark-colored paleosol layer, with an Rb/Sr ratio of 0.008, yielded an age of 287 +/- 32 yrs cal BP. These findings indicate that the paleosol developed around the 1700s, during one of the coldest phases of the Little Ice Age. This layer is followed by a brown-colored buried soil, indicating a short-lived humid and rainy period, as evidenced by an Rb/Sr ratio of 0.42.
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    Integrated geochemical, geoelectrical, and UAV-based methods for analyzing the Gzeylülaı landslide Çnkae(aakl, Tükyeri)
    (Tubitak Scientific & Technological Research Council Turkey, 2025) Erenoglu, Oya; Ulugergerli, Emin; Erenoglu, R. Cueneyt; Akbas, Abdullah; Erginal, A. Evren
    The number of reactivations increased in the G & uuml;zelyal & imath;-Erenk & ouml;y landslide area after 2013 in & Ccedil;anakkale, T & uuml;rkiye, where historical landslide activity has been recorded since 1875. This area is home to numerous summer residences and experiences ongoing slow-moving landslide activity along a 400-m-long slope, extending from the heavily trafficked & Ccedil;anakkale-& Idot;zmir highway to the coastline. In this study, the nature of the reactivations was evaluated by considering the conditioning and triggering factors that contributed to the landslide. The evaluation was based on geochemical analyses, field observations, geoelectric measurements, and unmanned aerial vehicle (UAV) data. The results revealed that the sliding occurred along a moist slip surface, rich in various clay minerals such as illite, montmorillonite, and vermiculite, at a depth of approximately 4.5 m, as determined by ERT (Electrical Resistivity Tomography). Vertical movements within the landslide area, including rises and subsidences, accounted for changes of up to 0.1 m between 2013 and 2023. Chemical Index of Weathering (CIW), Chemical Index of Alteration (CIA), and Plagioclase Index of Alteration (PIA) calculations obtained from the X-ray fluorescence (XRF) spectroscopy analysis indicate that the sliding surface is subjected to strong weathering, and these values are compatible with the X-Ray diffraction (XRD) data.
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    Öğe
    Termination of Little Ice Age in Northeastern Anatolia: A Multi-proxy Paleolimnology Study of Lake Aygir Sediments, (Kars, NE Anatolia)
    (Tmmob Jeoloji Muhendisleri Odasi, 2022) Erginal, Ahmet Evren; Yakupoglu, Nurettin; Cakir, Caglar; Akbas, Abdullah; Kukrer, Serkan
    Sedimentary, geochemical and stable isotope analyses of a sediment core (core AY) recovered from Lake Aygir (NE Anatolia) provide evidence of the climatic shifts during the last similar to 500 yrs. Sediments in Lake Aygir are composed of silty clay with a modeled similar to 0.16 cm/yr sedimentation rate. Multi-proxy analyses of the downcore distribution of detritally-deposited proxy elements, total calcium carbonate, organic carbon and stable isotopes reveal climatic records of the Industrial Epoch (IE; 18th-19th centuries) and the termination of the Little Ice Age (LIA; AD 1350 to 1850), represented by fluctuating Total Organic Carbon (TOC), Ca, Sr and relatively low detrital precursors (Fe, Ti, K, Rb, Zr), indicating low chemical weathering and dry conditions. The upper part of the core (192 cal yrs BP to present), identified with high detrital input, contains an increasing trend of Fe, Ti, K, Rb, and Zr together with high delta O-18 and delta C-13 values, indicating warmer conditions during the IE.