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Yayın Akdağ Kütlesi’nde (Batı Toroslar) Pleistosen buzullaşmalarının jeomorfolojik özellikleri ve optik uyarmalı lüminesans (OSL) ile yaşlandırılması(Türk Coğrafya Kurumu, 2017) Bayrakdar, Cihan; Güneç Kıyak, Nafiye; Turoğlu, Hüseyin; Öztürk, Tuğba; Canel, TimurBatı Torosların en yüksek ikinci zirvesine (Uyluk T. 3014 m) sahip olan Akdağ, batıda Eşen Ovası (60 m) doğuda Elmalı Ovası (1100 m) arasında yer alan ve 2700 m üzerinde birçok zirve barındıran, çevresine göre oldukça yüksek bir kütle görünümündedir. Akdağ Kütlesi'nde Kuvaterner'de meydana gelen buzul şekillerini incelemek ve OSL ile tarihlendirmek çalışmanın temel amacıdır. Bu çalışmada coğrafi bilgi sistemleri ve morfometrik analizler, OSL tarihlendirme yöntemi ve sedimantolojik analizlerden faydalanılmıştır. Akdağ Kütlesi'nin jeomorfolojik gelişiminde birden fazla etken ve sürecin rolü olmuştur. Bu süreçlerin başında karst, buzul, tektonik ve flüviyal gelmektedir. Akdağ Kütlesi'nde etkili olan Pleistosen buzullaşmaları, büyük ölçüde karstik yapıya uyumlu gelişmiş ve 2500 m ve üzerindeki paleo-karstik depresyonlarda kalın plato buzulları oluşmuştur. Akdağ Kütlesi'nde üçü büyük, beş buzul vadisi tespit edilmiştir. Bu buzul vadileri gelişmiş sirklerle başlayıp 2500 m seviyelerinde paleokarstik depresyonlara uyumlu olarak düşük eğimli, geniştabanlı ve büyük ölçüde taban ve yanal morenleri ile kaplı iken 2500 m seviyelerinden sonra vadiler daralıp klasik tekne vadi formu alıp 2000 m seviyelerinde cephe morenleri ile sonlanırlar. Akdağ Kütlesi'nde morenlerden alınan örneklere ait OSL tarihlendirmelerinde 17-21 bin yaşları çıkmıştır ki bu da son buzul dönemi MIS 2 ye denk gelmektedir.Yayın A new late holocene eolianite record from Altinkum Beach, North Cyprus(Scientific technical research council Turkey-Tubitak, 2012-06) Erginal, Ahmet Evren; Güneç Kıyak, Nafiye; Ertek, Topçu AhmetIn this study, we investigated the main depositional characteristics and obtained Optically Stimulated Luminescence (OSL) ages of coastal eolianite on the north coast of Cyprus, where this occurrence had not previously been recorded. Based on EDX/SEM and XRD data and field observations, the studied eolianite that crops out between elevations of 1 m and 14 m a.s.l. is made up predominantly of quartz grains, most of which consist of medium- to fine-grained sand. The rock comprises aragonite, calcite and quartz with lesser amounts of bornite and hematite as accessory minerals. OSL ages indicated that the initial deposition of eolianite sands took place at 1.51 +/- 0.21 ka years ago.Yayın Optically stimulated luminescence to date coastel dunes and a possible tsunami layer on the Kavak Delta (Saros Gulf, NW Turkey)(Scientific Technical Research Council Turkey-Tubitak, 2009-01-21) Erginal, Ahmet Evren; Güneç Kıyak, Nafiye; Özcan, HasanOptically stimulated luminescence (OSL) dating was used to determine the timing of initial dune formation and reconstruct the evolution of coastal dunes that developed on the Kavak Delta, Saros Gulf, Turkey. Along a 500-mlong representative transect, dune sands were extracted from foredune, semistable (grey) dune, stable (dark) dune and dune-swamp boundary defined by a scarp 50?75 cm high. The data obtained showed that dune drift initiated 670 years ago. A pumice layer 15?20-cm-thick interbedded with marine clay and sand showed an OSL age of 340 years coinciding with underlying dune sand. XRF analysis showed that pumices were of similar composition to those erupted by plinian activity of Thera (Santorini) in 1628 BC. On the basis of OSL ages, these deposits, which are widely distributed on the western Anatolian coasts of Turkey, might have presumably transported landward along tide channels on the delta during a tsunami event that occurred in 1672 near Bozcaada and Kos islands according to tsunami history of the Aegean Sea.Yayın A comparative morphological, compositional and tl study of tenedos (Bozcaada) and Sile aeolianites, Turkey(Univ Agean, 2012) Polymeris, George S.; Erginal, Ahmet Evren; Güneç Kıyak, NafiyeAeolianites are carbonate-cemented deposits of coastal dune sands, mostly of Quaternary age. Even though aeolianite exposures on the coasts of the Mediterranean Sea are frequent, very few records have been documented from the coasts of either the Aegean or the Black Sea. The present study deals with evaluating and comparing both compositions and thermoluminescence (TL) ages of two recently reported samples of coastal aeolianites. Both were recovered at the Turkish coasts of Tenedos (Bozcaada) island, Aegean Sea and Şile, Western Black Sea. In the latter case, being the first record for the specific coastal area, the oldest age obtained was dated at 158±25 ka while the youngest age yielded was 108±14 ka. These values imply that both deposition and cementation occurred during the high sea stand of marine isotope stage 5 (MIS 5). In the case of Tenedos, the aeolianites were deposited between the early stage of the oxygen isotope stage 2 period (OIS 2) and the very late phase of the oxygen isotope stage 3 period (OIS 3). These latter TL results are in excellent agreement with a previous study of the same complex after applying OSL. Besides the ages, a number of luminescent features and properties in conjunction with compositional data suggest the dissimilarity for the quartz samples extracted from the aeolianites recovered at these two sampling sites, excluding thus any transport from one sampling site to the other, despite the short distance of the two sampling sites and the meteorological data regarding the preferable wind directions between them.Yayın Kütahya fay zonu’nun Holosen aktivitesi(TMMOB Jeoloji Mühendisleri Odası, 2012-01) Altınok, Sevgi; Karabacak, Volkan; Yalçıner, Cahit Çağlar; Bilgen, Abdurrahman Nejat; Altunel, Erhan; Güneç Kıyak, NafiyeBatı Anadolu Açılma Bölgesi’nin kuzeydoğu sınırında bulunan Kütahya Havzası BKB-DGD doğrultusunda uzanan bir çöküntü alanıdır ve güney kenarı belirgin bir morfoloji ile Kütahya Fay Zonu tarafından sınırlanmaktadır. Kütahya Fay Zonu boyunca jeolojik, jeomorfolojik ve jeofizik verilerden yararlanılarak yapılan çalışmalar sonucunda bu zonun, kuzey bloğun düştüğü normal fay geometrisine sahip 5 ayrı uzanımdan oluştuğu ve K50-70B doğrultusunda yaklaşık 22 km uzunluğa sahip olduğu ortaya konulmuştur. Paleosismolojik ve arkeosismolojik çalışmalar ise bu uzanım boyunca son 8000 yıl içinde yüzey kırığı oluşturan en az iki depremin meydana geldiğini ortaya koymaktadır. Bu depremlerden ilki M.Ö. 6000’li yıllarda, sonuncusu ise M.Ö. 1800’lü yıllarda Seyitömer Höyüğü’nde hasar oluşturan ve höyüğün terk edilmesine neden olan depremdir. Dolayısıyla, bu çalışmalar Kütahya Havzası’nın güneyini sınırlayan Kütahya Fay Zonu’nun Holosen’de tekrarlanan yıkıcı depremler ürettiğini ve geometrisi gözönünde bulundurulduğunda gelecekte de en az 6.5 büyüklüğünde deprem üretme potansiyeli bulunduğunu ortaya koymaktadır.Yayın On the origin and age of the Ariburnu Beachrock, Gelibolu Peninsula, Turkey(Scientific Technical Research Council Turkey-TUBITAK, 2008-03-13) Erginal, Ahmet Evren; Güneç Kıyak, Nafiye; Bozcu, Mustafa; Ertek, Topçu Ahmet; Güngüneş, Hakan; Sungur, Ali; Türker, GülenThe beachrock formation on the Ariburnu coast situated in the Gelibolu Peninsula has been studied by field observation, thin-section interpretation, physicochemical analyses including ICP-AES and SEM/EDS, and OSL dating. These analyses reveal the presence of different amounts of major (Si, Ca, Mg, K, Fe, Al and Na) and trace elements within the beachrock cement with Si (36.2%) and Ca (32.68%) dominating the overall composition. Beachrocks composed of highly-fractured and friable beds reach a total thickness of 80 cm extending from + 60 cm at the uppermost level down to-1 m at their most seaward extent and grade from conglomerate to lithic arkose in vertical section. The total amount of CaCO(3) ranges between 59.08% and 36% and the cement consists of high-Mg calcite based on EDS analysis. From SEM examination, four main morphologies were identified in cement material: (1) micritic coatings, (2) cryptocrystalline pore-filling cement, (3) meniscus cement and (4) microbial cement and suggest the presence of marine phreatic conditions with the exception of meniscus bridges, which imply that cementation may have been dominated by carbonate-rich meteoric waters at any successive stage of cementation. Five buried beachrock samples under unconsolidated beach sand were sampled for Optically Stimulated Luminescence (OSL) dating and show that the minimum and maximum ages of beachrock are 1.42 +/- 0.20 ka and 2.28 +/- 0.28 ka BP, respectively.Yayın Preliminary results towards the equivalence of transformed continuous-wave Optically Stimulated Luminescence (CW-OSL) and linearly-modulated (LM-OSL) signals in quartz(Versita, 2011-09) Kitis, George; Polymeris, George S.; Güneç Kıyak, Nafiye; Pagonis, VasilisThe present paper presents a comparative experimental study of two commonly measured Optically Stimulated Luminescence (OSL) signals in quartz. The experimental study measures both the continuous wave OSL (CW-OSL) and the linearly modulated (LM-OSL) signals from the same quartz sample for a range of stimulation temperatures between 180 and 280A degrees C, while the former is transformed to pseudo LM-OSL (ps LM-OSL). A computerized deconvolution curve analysis of the LM-OSL and ps LM-OSL signals was carried out, and the contributions of several OSL components to the initial OSL signal (0.1 s) were shown to be independent of the stimulation temperature used during the measurement. It was also found that the composite OSL (0.1 s) signal consists mainly of the first two OSL components present in the OSL curves. The equivalence of the ps LM-OSL (transformed CW-OSL) and of LM-OSL measurements was also examined by an appropriate choice of the experimental stimulation times, and of the stimulation power of the blue LEDs used during the measurement.Yayın First note on marine-like cementation of Late Holocene beachrock, Iznik Lake (Turkey)(Versita, 2012-03) Erginal, Ahmet Evren; Güneç Kıyak, Nafiye; Öztürk, Muhammed Zeynel; Yiğitbaş, Erdinç; Bozcu, Mustafa; Avcıoğlu, Mustafa; Öztürk, BeyhanMicro-fabric characteristics and optically stimulated luminescence (OSL) dating results are presented to discuss the controlling agents and timing of beachrock cementation on the fresh-water Iznik Lake shoreline. The beachrocks are made up of grain-supported polygenic conglomerate containing 20.42% carbonate with encrusted grains, basically as micrite coatings, isopachous aragonite rims, cryptocrystalline void fills and meniscus bridges. The optical ages of twelve samples yielded ages that range from 4.226 +/- 0.569 ka on the lowermost beds to 0.706 +/- 0.081 on the uppermost. This is the first report of precipitation of marine-like cements in Iznik Lake. The abundant aragonite-dominated cement is likely indicative of precipitation-prone dry evaporative conditions from the climatic optimum to the last millennia.Yayın Luminescence dating of prehistoric site of smintheion (Gulpinar) in NW Turkey(Univ Agean, Dept Mediterranean Stud, 2010) Güneç Kıyak, Nafiye; Takaoğlu, Turan; Erginal, Ahmet Evren; Özcan, HalilThis study aims to place the prehistoric settlement of Smintheion in northwestern Turkey in its temporal setting on the basis of the dating of the quartz from pottery and sediments collected from the site employing Optically Stimulated Luminescence and Thermoluminescence techniques. The site belongs to the problematic Middle Chalcolithic period in western Anatolia. This period represents a cultural upheaval in western Anatolia as it has a completely different material culture when compared to that of the preceding Early Chalcolithic period. The pottery and sediment samples were collected from two different locations of the Middle Chalcolithic settlement at Smintheion for dating study. The fact that this examined settlement is represented by a single cultural level provides an opportunity to obtain secure and reliable dates for the settlement. Results of this study show that the site can be dated to a period between 4800 and 4500 B.C.
