Yazarlar

  • MakaleYalnız künye2025Scopus SJRQ2
    Morphometric constraints on tectonic activity and landscape evolution in the Uludağ Range, NW Türkiye

    Sançar, Taylan; Karabacak, Volkan

    The Uluda & gbreve; Range of northwest T & uuml;rkiye forms a key tectonic boundary between the North Anatolian Fault Zone and the Western Anatolia Extensional Region, where active deformation is expressed across a network of strike-slip and normal faults. To investigate how fault segmentation and kinematics control landscape evolution in this complex orogen, we integrate high-resolution morphometric analysis with paleoseismological data. We extracted key morphometric indices-including Delta-relief, Delta-elevation, Delta-gradient, Delta chi, hypsometric integral, channel concavity (m/n), normalized channel steepness (ksn), and knickpoint distribution-from 10-meter DEMs using open-source geomorphic toolkits. Our results demonstrate pronounced spatial variability in geomorphic signatures and tectonic activity across four divide segments (DS). DS01, associated with the right-lateral Ulubat Fault, exhibits exceptional morphometric stability and minimal disequilibrium, in line with long earthquake recurrence intervals and low Holocene slip rates. In contrast, DS02 and DS03-bounded by the Bursa and So & gbreve;ukpinar faults-display chi-based divide migration and subtle landscape adjustment. DS04, influenced by the & Idot;neg & ouml;l and Oylat faults, is characterized by elevated channel steepness, dense knickpoint clustering, and southward divide migration, collectively indicating ongoing uplift and transient drainage adjustment. The strong correspondence between morphometric disequilibrium and documented earthquake recurrence patterns highlights the critical value of integrating geomorphic and paleoseismological datasets. Our findings demonstrate that only through the convergence and cross-validation of multiple independent metrics can the segmented imprint of active deformation be reliably detected-particularly where landscape response is temporally offset from fault activity. The methodological framework developed here provides a robust template for quantifying active structures and their geomorphic consequences and can be widely applied to other tectonically complex mountain belts for seismic hazard assessment and landscape evolution studies.

    AtıfWoS2OpenAlex2
    Web of Scienceİncele
  • MakaleAçık Erişim2023Scopus SJRQ2
    Paleoseismology of the Ganos segment; the western extend of the North Anatolian Fault (Turkey)

    Aksoy, Murat Ersen; Meghraoui, Mustapha; Ferry, Matthieu; Çakir, Ziyadin; Uçarkuş, Gülsen; Sançar, Taylan; Altin, Mehmet Uğur

    The Ganos fault that ruptured on 9 August 1912 (Mw: 7.4) is the westernmost inland segment of the North Anatolian fault (NAF). Here, the Ganos fault is bounded at its two tips with offshore faults segments, in the Sea of Marmara to the east and the Gulf of Saros to the west in the North Aegean Trough. Therefore, the paleoseismology of the 45-km-long inland fault is of importance to the seismic hazard analysis related to offshore active faults and in particular for the seismic gap in the Marmara Region. Earlier studies have established an earthquake chronology for the western and eastern inland tips of the Ganos fault. Here, we extend the paleoseismic studies toward the central segment. Three trenches at Yörgüç have revealed evidence for two faulting events, possibly post-1669 CE ±30 years, which can be correlated to the 1659 or 1766, and the 1912 historical earthquakes. At Yeniköy, we determined an offset of 46 ± 1 m and 47 ± 1 m on a stream channel and a ridge-crest, respectively. In two trenches we determined two faulting events for the last 1000 years and seven events for the last 3500 years. In trench T5, the base of the displaced stream channel provides a calibrated date of 829–591 BCE. Using the 46 ± 1 m right-lateral displacement, we calculate a slip rate of 16.9 ± 0.7 mm/year for the last 2732 ± 119 years. A combined analysis with earlier paleoseismic studies on the Ganos fault suggests that the historical earthquakes of 1912, 1766b or 1659, 1354 or 1343a, and 1063 ruptured the entire inland fault section. In such a case, the recurrence interval for this section of the NAF corresponds to 283 ± 81 years. Combining earlier estimations, we suggest an average slip rate of 17.1 ± 0.9 mm/year for the last 2700 years and observe a characteristic slip behavior of 4.5 to 5 m per event for this section of the North Anatolian plate boundary fault.

    AtıfScopus1OpenAlex2
    ScopusWeb of ScienceTR Dizinİncele
  • MakaleYalnız künye2017Scopus SJRQ2
    Palaeoseismic history of the eastern part of the North Anatolian Fault (Erzincan, Turkey): Implications for the seismicity of the Yedisu seismic gap

    Zabci, Cengiz; Akyüz, H. Serdar; Sançar, Taylan

    The North Anatolian Fault showed a remarkable seismic activity especially between 1939 and 1999, when the westward migrating earthquake sequence created surface ruptures more than 1000 km, leaving unbroken only the Marmara segments, to the west, and the Yedisu Segment, to the east along the main strand of the fault. To understand the palaeoseismicity of the Yedisu Seismic Gap, we undertook trench investigations close to the village of Balaban SarA +/- kaya, on the western part of the Yedisu Segment. We found evidence for at least five surface faulting earthquakes, from which only two are correlated with the 18 July 1784 CE and 27 June 1583 CE historical events. Although the surface rupture of the 1784 CE was reported by other trench studies, the evidence of 1583 CE event is presented for the first time. In consideration with other historical earthquakes, affecting the region east of Erzincan, we suggest that this particular section of the North Anatolian Fault may be in a seismically quiescent period, following a cluster of earthquakes in its near history. In order to test this hypothesis, further studies are needed to increase our knowledge on the temporal and spatial seismic behaviour of the Yedisu Segment, which has potential to create an earthquake with M (w) similar to 7.2 in the near future.

    AtıfWoS15OpenAlex23
    Web of Scienceİncele