Yazarlar

  • MakaleYalnız künye2018Scopus SJRQ2
    Earthquake hazard potential in the Eastern Anatolian Region of Turkey: seismotectonic b and Dc-values and precursory quiescence Z-value

    Öztürk, S.

    The Eastern Anatolian Region of Turkey is one of the most seismically and tectonically active regions due to the frequent occurrence of earthquakes. Thus, the main goal of this study is to analyze the regional and temporal characteristics of seismicity in the Eastern Anatolia in terms of the seismotectonic b-value, fractal dimension Dc-value, precursory seismic quiescence Z-value, and their interrelationships. This study also seeks to obtain a reliable empirical relation between b and Dc-values and to evaluate the temporal changes of these parameters as they relate to the earthquake potential of the region. A more up-to-date relation of Dc = 2:55–0:39*b is found with a very strong negative correlation coefficient (r =–0.95) by using the orthogonal regression method. The b-values less than 1.0 and the Dc-values greater than 2.2 are observed in the Northeast Anatolian Fault Zone, Aşkale, Erzurum, Iğdır and Çaldıran Faults, Doğubeyazıt Fault Zone, around the Genç Fault, the western part of the Bitlis-Zagros Thrust Zone, Pülümür and Karakoçan Faults, and the Sancak- Uzunpınar Fault Zone. In addition, the regions having small b-values and large Z-values are calculated around the Genç, Pülümür and Karakoçan Faults as well as the Sancak-Uzunpınar Fault Zone. Remarkably, the combinations of these seismotectonic parameters could reveal the earthquake hazard potential in the Eastern Anatolian Region of Turkey, thus creating an increased interest in these anomaly regions.

    AtıfScopus51WoS36OpenAlex53
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2017Scopus SJRQ2
    Spatial and temporal analysis of recent seismicity in different parts of the vlora-lushnja-elbasani-dibra transversal fault zone, Albania

    Ormeni, Rrapo; öZtürk, Serkan; Fundo, Akli; çElik, Kemal

    Spatial and temporal evaluation of current seismic activity throughout the Vlora- Lushnja-Elbasani-Dibra (VLED) transversal fault zone were carried out at the beginning of year 2016. The seismotectonic b-value, fractal dimension Dc-value and precursory seismic quiescence Z-value are considered for a detailed statistical analysis. Completeness magnitude Mc-value varies from 2.5 to 2.7 for different parts of the VLED fault zone. The b-value is calculated as 1.10±0.04 for the south western part and 1.13±0.05 for the middle part, whereas it is estimated as 0.94±0.07 for the north eastern part of the study region. These results reveal that b-values for all regions are well represented by a b-value typically close to 1.0. There are clear decreasing trends in temporal changes of b-values before the occurrences of some strong main shocks. On the contrary, no earthquakes are observed in some periods after decrease of b-value. Dc-values are computed as 2.66±0.04 for the south western part, 2.64±0.03 for the middle part and 2.15±0.02 for the north eastern part of the VLED fault zone. These rather large values show that earthquake activity is more clustered at larger scales or in smaller areas in the study area. Considering the phenomenon of seismic quiescence as a precursor of the main earthquakes gives successful outcomes in defining the potential anomalies and possible locations of future earthquakes. Quiescence analysis of current seismicity at the beginning of 2016 in the VLED fault zone is performed with the test of standard normal deviate Z-value. Distributions of resulting Z-values show six anomalous regions along the different parts of the VLED fault zone. These quiescence areas are detected at (i) 40.81°N- 19.86°E (including Kuc-Bubullim, southeast of Lushnja town), (ii) 41.00°N-20.01°E (in the Cerriku, south of Elbasani town), (iii) 41.31°N-20.13°E (around Bene-Qafe, northeast of Elbasani town), (iv) 41.43°N-20.21°E (Krasta-Batra, south of Bulqiza town), (v) 41.28°N-20.49°E (including Carrishta-Stebleve, northeast of Librazhdi town), (vi) 41.51°N-20.51°E (including Qerrenec-Gjorica, west of Dibra town). As an important result, analyses of spatial and temporal characteristics of the earthquake activity may supply significant clues for revealing the future seismic hazard along the VLED fault zone, and these anomaly regions may be interpreted as the locations of next possible earthquakes.

    AtıfScopus11WoS6OpenAlex11
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2013Scopus SJRQ2
    A statistical assessment of current seismic quiescence along the North Anatolian fault zone: Earthquake precursors

    Öztürk, Serkan

    The variations of the current seismicity rate on the North Anatolian Fault Zone in the beginning of 2009 have been analyzed based on the phenomenon of precursory seismic sequence before crustal main shocks. For this purpose, a statistical assessment is made to detect the seismic quiescence situation by using the standard normal deviate Z-value. Eight seismic quiescence regions are observed and quiescence anomalies in these regions have been observed since the beginning of 2005. On the Marmara part of the North Anatolian Fault Zone, four quiescence areas have been found on Silivri, in the Black Sea, around Izmit region and Çanakkale, Saros Gulf. On the Anatolian part of the North Anatolian Fault Zone, two quiescence areas have been observed on the Düzce fault and around the city of Amasya. Other anomalies have been observed around Erzincan, Elaziǧ and Bingöl regions on the eastern part of the North Anatolian Fault Zone. Due to the occurrences of the last strong earthquakes "MW = 6.0-Elaziǧ earthquake, 2010 March 08; MW = 5.2 - Çanakkale (Saros Gulf) earthquake, 2010 November 03; MW = 5.5-Erzincan earthquake, 2011 September 22 and MW = 5.1-Marmara Ereǧlisi (Tekirdaǧ) earthquake, 2012 June 07", other seismic quiescence regions may contribute to the forecasting of impending main shocks. Spatial and temporal estimates of the future seismic hazard of the North Anatolian Fault Zone are provided based on the results.

    AtıfScopus14WoS10
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2012Scopus SJRQ3
    Spatial variations of precursory seismic quiescence observed in recent years in the eastern part of Turkey

    Öztürk, Serkan; Bayrak, Yusuf

    A statistical analysis is made for the eastern part of Turkey in the beginning of 2009 by studying the phenomenon of seismic quiescence as a potential precursor of the main shocks. The results produced four areas having seismic quiescence in the beginning of 2009. These areas are observed to be centered at 39.96°N-40.69°E (around Aşkale, Erzurum), 39.36°N-39.74°E (around Ovaci{dotless}k, Tunceli), 39.02°N-40.52°E (including Elazi{dotless}ǧ and Bingöl), and 38.45°N-42.94°E (Van Lake). Based on the recent results showing 5 ± 1.5 years quiescence before the occurrence of an earthquake in this region, the future earthquake would be expected between 2009. 5 and 2010. 5. The future earthquake occurrence may reach 2012 if we consider the standard deviation of average seismic quiescence as ±1.5 years. We have found that the MW = 6.0 Elazi{dotless}ǧ earthquake on 8 March 2010, followed a seismic quiescence starting about 5 years before the main shock. Thus, special interest should be given to the other regions where the seismic quiescence is observed.

    AtıfScopus27WoS22OpenAlex30
    ScopusWeb of Scienceİncele