ÇALDIRAN FAY ZONU VE CIVARINDAKI COULOMB STRESS TRANSFERI VE DEPREM TEHLIKESI ANALIZI

Öz

Çaldıran fay zonu (CFZ) bir çok yıkıcı deprem üreten ve depremsellik açısından önemli bir aktif zondur. Bu fay sisteminde, 1976 tarihinde bu yıkıcı depremlerin en sonuncusu (Ms = 7.3) meydana gelmiştir. Dolayısıyla bu fay zonunda sismotektonik b-değeri, deprem olasılığı, tekrarlama zamanı ve Coulomb gerilme değişimi parametrelerine bağlı olarak gelecek deprem potansiyeli ve pozitif/negatif gerilme değişimleri araştırılmıştır. Büyüklüğü 3.6'dan büyük olan depremler, sismotektonik parametrelerle ilgili olarak gerilme transfer yönünü araştırmak için kullanılmıştır. Çalışmanın sonuçlarına göre, CFZ’nin güneydoğusu boyunca küçük b değerleri elde edilmişken, büyük b değerleri Van Gölünün doğusu civarında hesaplanmıştır. Diğer taraftan, CFZ’nin kuzeydoğusu mevcut stress birikimini temsil etmektedir. Benzer şekilde, 1976 depreminin Coulomb gerilme değişimi bu fay sisteminin kuzeybatısında gerilmelerin farklı derinliklerde biriktiğini göstermektedir. Ayrıca, daha önceki çalışmalardaki uzun dönem kayma oranları ve yatay öteleme değerleri dikkate alındığında, 6.0'dan büyük bir deprem için tekrarlama zamanı yaklaşık 302 yıldır. Sonuç olarak, bu karşılaştırmalı analizler bölgede sismik tehlike değerlendirmesinin etkilerini ve olası bir sonraki deprem oluşumunun tahminini açıklamaktadır.

Anahtar Kelimeler

• Çaldıran Fay Zonu
• B-Değeri
• Deprem Olasılığı
• Tekrarlama Zamanı
• Coulomb Gerilme Değişimi

ANALYSIS OF COULOMB STRESS TRANSFER AND EARTHQUAKE HAZARD IN THE ÇALDIRAN FAULT ZONE AND ITS ADJACENT REGION

Öz

Çaldıran fault zone (CFZ) are significant seismically active zone that generated many destructive earthquakes. In this fault system, the last of these major earthquakes occurred on 1976 (Ms = 7.3). Therefore, based on the seismotectonic b-value, earthquake probability, recurrence times and Coulomb stress changes, we investigate the future earthquake potential and positive/negative stress changes in this fault zone. The events with a magnitude greater than 3.6 are used to investigate stress transfer direction regarding the seismotectonic parameters. The results indicate that the regions having smaller b-values are obtained along with the SE of CFZ, whilst higher b-values are calculated around the east of Lake Van. On the other hand, the northeast of CFZ represents current stress accumulation. Similarly, the Coulomb stress variations of 1976 earthquake show that stress accumulated at different depths in the northwest of this fault system. In addition, considering the long-term slip rates and horizontal offset in previous studies, the recurrence time of earthquakes has approximately 302 years for a magnitude greater than 6.0. Finally, these comprehensive analyses explain the implications of seismic hazard evaluation and forecasting of possible next earthquake occurrences in this region.

Anahtar Kelimeler

• Çaldıran Fault Zone
• B-Value
• Earthquake Probability
• Recurrence Time
• Coulomb Stress Variation

Kaynakça

1. Ali, S.M., 2016. Statistical analysis of seismicity in Egypt and its surroundings. Arab. J. Geosci., 9, 52.
2. Ambraseys, N.N., 2009. Earthquakes in the Mediterranean and Middle East, Cambridge University Press, New York.
3. Bayrak, Y., Öztürk, S., Çınar, H., Kalafat, D., Tsapanos, T., Koravos, G-Ch., Leventakis, G.A., 2009. Estimating earthquake hazard parameters from instrumental data for different regions in and around Turkey. Eng. Geol., 105, 200-210.
4. Akinci, A., Antonioli, A., 2013. Observations and stochastic modelling of strong ground motions for the 2011 October 23 Mw 7.1 Van, Turkey, earthquake. Geophys. J. Int., 192, 1217-1239.
5. Alkan, H., Çınar, H., Oreshin, S., 2020. Lake Van (southeastern Turkey) experiment: Receiver function analyses of lithospheric structure from teleseismic observations. Pure Appl. Geophys., 177, 3891-3909.
6. Alkan, A., Akkaya, İ., 2021. Investigation of Çaldıran (Van) Settlement Area Under the Effect of Active Tectonics by Surface Wave Methods. Bitlis Eren University Journal of Science, 10 (4), 1435-1447.
7. Alkan, H., Bayrak, E., 2021. Coulomb Stress Changes and Magnitude-Frequency Distribution for Lake Van Region. Bulletin of the Mineral Research and Exploration, 168, 141-156.
8. Bayrak, Y., Yadav, R.B.S., Kalafat, D., Tsapanos, T.M., Çınar, H., Singh, A.P., Bayrak, E., Yılmaz, Ş., Öcal, F., Koravos, G., 2013. Seismogenesis and earthquake triggering during the Van (Turkey) 2011 seismic sequence. Tectonophysics, 601, 163-176.

9. Bozkurt, E., 2001. Neotectonics of Turkey - a synthesis. Geodin. Acta., 14, 3-30.
10. Copley, A., Jackson, J., 2006. Active tectonics of the Turkish-Iranian Plateau. Tectonics, 25, TC6006.
11. Delph, J., Biryol, C.B., Beck, S.L., Zandt, G., Ward, K.M., 2015. Shear wave velocity structure of the Anatolian Plate: anomalously slow crust in southwestern Turkey. Geophys. J. Int., 202, 261-276.
12. Djamour, Y., Vernant, P., Nankali, H.R., Tavakoli, F., 2011. NW Iran-eastern Turkey present-day kinematics: Results from the Iranian permanent GPS network. Earth and Planetary Science Letters, 307, 27-34.
13. Elliott, J.R., Copley, A.C., Holley, R., Scharer, K., Parsons, B., 2013. The 2011 Mw 7.1 Van (Eastern Turkey) earthquake. J. Geophys. Res. Solid Earth, 118, 1619-1637.
14. Emre, O., Duman, T.Y., Ozalp, S., Saroglu, F., Olgun, S., Elmaci, H., Can, T., 2018. Active fault database of Turkey. Bulletin of Earthquake Engineering, 16, 3229-3275.
15. Frohlich, C., Davis, S., 1993. Teleseismic b-values: Or, much ado about 1.0. J. Geophys. Res., 98(B1), 631-644.
16. Gutenberg, B., Richter, F., 1944. Frequency of earthquakes in California. B. Seismol. Soc. Am., 34, 185-188.
17. Irmak, T.S., Doğan, B., Karakaş, A., 2012. Source mechanism of the 23 October, 2011, Van (Turkey) earthquake (Mw= 7.1) and aftershocks with its tectonic implications. Earth Planets Space, 64, 991-1003.
18. King, G.C., Stein, R.S., Lin, J., 1994. Static stress changes and the triggering of earthquakes. Bull. Seismol. Soc. Am., 84(3), 935-953.
19. Koçyiğit, A., Yılmaz, A., Adamia, S., Kuloshvili, S., 2001. Neotectonics of East Anatolian Plateau (Turkey) and Lesser Caucasus: implication for transition from thrusting to strike-slip faulting. Geodinamica Acta, 14, 177-195.
20. Mackenzie, D., Elliott, J.R., Altunel, E., Walker, R.T., Kurban, Y.C., Schwenninger, J.L., Parsons, B., 2016. Seismotectonics and rupture process of the M 7.1 2011 Van reverse-faulting earthquake, eastern Turkey, and implications for hazard in regions of distributed shortening. Geophysical Journal International, 206, 501-524.
21. McClusky, S., Balassanian, S., Barka, A., Demir, C., Ergintav, S., Georgiev, I., Gurkan, O., Hamburger, M., Hurst, K., Kahle, H., Kastens, K., Kekelidze, G., King, R., Kotzev, V., Lenk, O., Mahmoud, S., Mishin, A., Nadariya, M., Ouzounis, A., Paradissis, D., Peter, Y., Prilepin, M., Reilinger, R., Sanli, I., Seeger, H., Tealeb, A., Toksöz, M.N., Veis, G., 2000. GPS constraints on plate motions and deformation in the Eastern Mediterranean: implications for plate dynamics. J. Geophys. Res., 105, 5695-5719.
22. Ottemöller, L., Voss, P.H., Havskov, J., 2021. SEISAN Earthquake Analysis Software for Windows, Solaris, Linux and Macosx, Version 12.0. 607 pp. University of Bergen, ISBN 978-82-8088-501-2.
23. Mogi, K., 1962. Magnitude-frequency relation for elastic shocks accompanying fractures of various materials and some related problems in earthquakes. Bulletin of the Earthquake Research Institute, Tokyo University, 40, 831-853.
24. Ozer, C., Ozyaziciglu, M., Gök, E., Polat, O., 2019. Imaging the Crustal Structure Throughout the East Anatolian Fault Zone, Turkey, by Local Earthquake Tomography. Pure Appl. Geophys., 176, 2235-2261.
25. Öztürk, S., 2009. An application of the earthquake hazard and aftershock probability evaluation methods to Turkey earthquakes. PhD Thesis, Karadeniz Technical University, Trabzon, Turkey (in Turkish with English abstract).
26. Öztürk, S., 2015. Fractal Dimension of Seismicity and a Modeling on the Intermediate-Term Forecasting for the Locations of Expected Strong Earthquakes: Eastern Anatolian Region, Turkey. Gümüşhane University Journal of Science and Technology Institute, 5(1), 1-23 (in Turkish with English abstract).
27. Öztürk, S., 2017. Space-time assessing of the earthquake potential in recent years in the Eastern Anatolia region of Turkey. Earth Sci. Res. J., 21, 2, 67-75.
28. Öztürk, S., 2018. Earthquake hazard potential in the Eastern Anatolian Region of Turkey: seismotectonic b and Dc-values and precursory quiescence Z-value. Front Earth Sci., 12(1), 215-236.
29. Reasenberg, P., Oppenheimer, D., 1985. Fpfit, Fpplot, and Fppage: Fortran computer programs for calculating and displaying earthquake fault plane solutions. Technical report, U.S. Geol. Survey.
30. Reilinger, R., McClusky, S., Vernant, P., Lawrence, S., Ergintav, S., Cakmak, R., Ozener, H., Kadirov, F., Guliev, I., Stepanyan, R., Nadariya, M., Hahubia, G., Mahmoud, S., Sakr, K., ArRajehi, A., Paradissis, D., Al-Aydurs, A., Prilepin, M., Guseva, T., Evren, E., Dmitrotsa, A., Filikov, S.V., Gomez, F., Al-Ghazzi, R., Karam, G., 2006. GPS constraints on continental deformation in the Africa-Arabia-Eurasia continental collision zone and implications for the dynamics of plate interactions. Journal of Geophysical Research Solid Earth, 111(B5), B05411.
31. Scholz, C.H., 2015. On the stress dependence of the earthquake b value. Geophys. Res. Lett., 42, 1399-1402.
32. Selçuk, A.S., Erturaç, M.K., Nomade, S., 2016. Geology of the Çaldıran Fault, Eastern Turkey: Age, slip rate and implications on the characteristic slip behaviour. Tectonophysics, 680, 155-173.
33. Suetsugu, D., 1998. Practice on source mechanism, iisee lecture note. Technical report Tsukuba, Japan.
34. Stein, R.S., King, G.C.P., Lin, J., 1994. Stress Triggering of the 1994 M = 6.7 Northridge, California, earthquake by its predecessors. Science, 265(5177), 1432-1435.
35. Şaroğlu, F., 1986. Geological and structural evolution of East Anatolia during the Neotectonic period, Unpublished PhD Thesis, İstanbul University, Department of Geological Engineering, 240 page.
36. Şaroğlu, F., Yılmaz, Y., 1986. Doğu Anadolu’da Neotektonik Dönemdeki Jeolojik Evrim ve Havza Modelleri, MTA Genel Müdürlüğü, Jeoloji Etütleri Dairesi, Ankara (in Turkish).
37. Şengör, A.M.C., Ozeren, S., Genç, T., Zor, E., 2003. East Anatolian high plateau as a mantle-supported, north-south shortened domal structure. Geophys. Res. Lett., 30, 24:8045.
38. Reilinger, R., McClusky, S., Vernant, P., Lawrence, S.. Ergintav, S., Cakmak, R., et al., 2006. GPS constraints on continental deformation in the Africa‐Arabia‐Eurasia continental collision zone and implications for the dynamics of plate interactions. Journal of Geophysical Research: Solid Earth, 111(B5).
39. Toda, S., Stein, R.S., Sevilgen, V., Lin, J., 2011. Coulomb 3.3 Graphic-rich deformation and stress-change software for earthquake, tectonic, and volcano research and teaching-user guide. U.S. Geological Survey Open-File Report, 2011-1060, 63.
40. Toker, M., Pınar, A., Hoşkan, N., 2021. An integrated critical approach to off-fault strike-slip motion triggered by the 2011 Van mainshock (Mw 7.1), Eastern Anatolia (Turkey): New stress field constraints on subcrustal deformation. Journal of Geodynamics, 147, 101861.
41. Tsapanos, T.M., Bayrak, Y., Çınar, H., Koravos, G.C., Bayrak, E., Kalogirou, E.E., Tsapanou, V., Vougiouka, E., 2014. Analysis of Largest Earthquakes in Turkey and its Vicinity by Application of the Gumbel III Distribution. Acta Geophysica, 62, 1, 59-82.
42. Utkucu, M., Durmuş, H., Yalçın, H., Budakoğlu, E., Işık, E., 2013. Coulomb static stress changes before and after the 23 October 2011 Van, eastern Turkey, earthquake (M = 7.1): implications for the earthquake hazard mitigation. Nat. Hazards. Earth Syst. Sci., 13, 1889-1902.
43. Wang, C., Ding, X., Li, Q., Shan, X., Zhu, W., Guo, B., Liu, P., 2015. Coseismic and postseismic slip models of the 2011 Van earthquake, Turkey, from InSAR, offset-tracking, MAI, and GPS observations. Journal of Geodynamics, 91, 39-50.
44. Utsu, T., 1971. Aftershock and earthquake statistic (III): Analyses of the distribution of earthquakes in magnitude, time and space with special consideration to clustering characteristics of earthquake occurrence (1). Journal of Faculty of Science Hokkaido University Series VII (Geophysics) 3, 379-441.
45. Wessel, P., Smith, W.H.F., Scharroo, R., Luis, J.F., Wobbe, F., 2013. Generic mapping tools: improved version released. EOS Transaction AGU, 94, 409-410.
46. Wiemer, S., Wyss, M., 2000. Minimum magnitude of completeness in earthquake catalogs: Examples from Alaska, the Western United States, and Japan. B. Seismol. Soc. Am., 90(3), 859-869.
47. Wiemer, S., 2001. A software package to analyze seismicity: ZMAP. Seismological Research Letters, 72(3), 373-382.
48. Yadav, R.B.S., Gahalaut, V.K., Chopra, S.B., 2012. Tectonic implications and seismicity triggering during the 2008 Baluchistan, Pakistan earthquake sequence. J. Asian Earth Sci., 45, 167-178.
49. Yiğitbaş, E., Elmas, A., Sefunç, A., Özer, N., 2004. Major neotectonic features of eastern Marmara region, Turkey: development of the Adapazarı–Karasu corridor and its tectonic significance. Geological Journal, 39, 179-198.
50. URL-1 . https://deprem.afad.gov.tr/ddakatalogu, Accessed 2022.
51. URL-2 https://earthquake.usgs.gov/earthquakes/map, Accessed 2022.
52. URL-3 http://www.koeri.boun.edu.tr/sismo/2/earthquake-catalog, Accessed 2022.