Abstract—A devastating earthquake with magnitude Mw = 7.2 occurred in the Van region, Eastern Turkey, on October 23, 2011. This study analyzes the characteristics of surface deformation before, during, and after the earthquake. The data from 300 × 300 km2 permanent GPS network are used to quantitatively estimate surface deformations in the epicentral zone of the earthquake in the interval from January 16, 2009 to October 29, 2012 with daily time resolution. The dilatation, total shear, horizontal and vertical displacements are determined approximately three years before and one year after the 2011 Van earthquake. The spatial distributions of strains for each day are combined into a video to track the variations in the deformation process before and after the earthquake. The anomalous deformations are revealed a few months before the earthquake at a distance of about 100 km from the future epicenter. The evolution of the motions and deformations in the study region indicates a probable connection between the development of anomalous strains in the Varto fault zone and Bitlis–Zagros suture zone and the preparation of the Van earthquake. This suggests that preparatory deformation processes may take place at distances of dozens and hundreds km from the future seismic source.
Similar content being viewed by others
REFERENCES
AFAD (Disaster and Emergency Management Presidency of Turkey), Van depremi raporu, 2011. https://deprem.afad. gov.tr/?lang=en
Altıner, Y., Söhne, W., Güney, C., Perlt, J., Wang, R., and Muzli, M., A geodetic study of the 23 October 2011 Van, Turkey earthquake, Tectonophysics, 2013, vol. 588, pp. 118–134. https://doi.org/10.1016/j.tecto.2012.12.005
Blewitt, G., Hammond, W.C., and Kreemer, C., Harnessing the GPS data explosion for interdisciplinary science, Eos, 99, 2018. https://doi.org/10.1029/2018EO104623
Bowman, D.D., Oullion, G., Sammis, C.G., Sorentte, A., and Sorentte, D., An observational test of critical earthquake concept, J. Geophys. Res., 1988, vol. 103, no. B10, pp. 24359–24372.
Bozkurt, E., Neotectonics of Turkey—a synthesis, Geodyn. Acta, 2001, vol. 14, nos. 1–3, pp. 3–30. https://doi.org/10.1080/09853111.2001.11432432
Delaunay, B., Sur la sphère vide. A la mémoire de Georges Voronoï, Izv. Akad. Nauk SSSR, Otd. Mat. Estestv. Nauk, 1934, no. 6, pp. 793–800.
Dobrovolsky, I.P., Zubkov, S.I., and Miachkin, V.I., Estimation of the size of earthquake preparation zones, Pure Appl. Geophys., 1979, vol. 117, no. 5, pp. 1025–1044.
Dokukin, P.A., Kaftan, V.I., and Krasnoperov, R.I., Influence of the shape of triangles in a geodetic network on the results of determining the deformations of the Earth’s surface, Izv. Vyssh. Uchebn. Zaved., Geod. Aerofotos”emka, 2010, no. 5, pp. 6–11.
Emre, Ö., Duman, T., Özalp, S., Elmacı, H., 23 Ekim 2011 Van depremi saha gözlemleri ve kaynak faya ilişkin ön değerlendirmeler, Ankara: General Directorate of Mineral Research and Exploration (MTA), 2011, vol. 22.
Emre, Ö., Duman, T., Olgun, Ş., Elmacı, H., and Özalp, S., 1/250 000 ölçekli Türkiye Diri Fay Haritası Serisi, Ankara: General Directorate of Mineral Research and Exploration (MTA), 2012.
Gu, G. and Wang, W., Far-field crustal movement before and after the 2011 Ms 9.0 Japan earthquake from GPS observations, Geod. Geodyn, 2011, vol. 2, no. 3, pp. 1–7.
Gu, G., Wang, W., Xu, Y., and Li, W., Horizontal crustal movement before the great Wenchuan earthquake obtained from GPS observations in the regional network, Earthq. Sci., 2009, vol. 22, no. 5, pp. 471–478. https://doi.org/10.1007/s11589-009-0471-x
Gu, G., Guojie, M., and Wang, W., Anomalous crustal movements before great Wechuan earthquake observed by GPS, Geod. Geodyn., 2011, vol. 2, no. 2, pp. 13–22. https://doi.org/10.3724/SP.J.1246.2011.00013
Kaftan, V. and Melnikov, A., Local deformation precursors of large earthquakes derived from GNSS observation data, JOP Conf. Ser.: Earth Environ. Sci., 2017, vol. 95, no. 3, Paper ID 03203. https://doi.org/10.1088/1755-1315/95/3/032030
Kaftan, V.I. and Ostach, O.M., Vertical land deformation in Caucasus region, Earthquake Predict. Res., 1996, no. 5, pp. 235–245.
Keskin, M., Magma generation by slab steepening and break off beneath a subductionaccretion complex: An alternative model for collision-related volcanism in Eastern Anatolia, Turkey, Geophys. Res. Lett., 2003, vol. 30, no. 24, Paper ID 8046. https://doi.org/10.1029/2003GL018019
Koçyiğit, A., New field and seismic data about the intraplate strike-slip deformation in Van region, East Anatolian plateau, E. Turkey, J. Asian Earth Sci., 2013, vol. 62, pp. 586–605. https://doi.org/10.1016/j.jseaes.2012.11.008
Koçyiğit, A., Yilmaz, A., Adamia, S., and Kuloshvili, S., Neotectonics of East Anatolian plateau (Turkey) and lesser Caucasus: implication for transition from thrusting to strike-slip faulting, Geodyn. Acta, 2001, vol. 14, nos. 1–3, pp. 177–195. https://doi.org/10.1080/09853111.2001.11432443
Koçyiğit, A., Özer, M.F., Lenk, O., Çolakoğlu, Z., Çelebi, M., Holzer, T., Sharer, K., and Havskov, J., Report on October 23, 2011 Van Earthquake Mw 7.0.pdf. 2012. http://www.deprem. gov.tr. Cited September 2012.
Mackenzie, D., Elliott, J.R., Altunel, E., Walker, R.T., Kurban, Y.C., Schwenninger, J.-L., and Parsons, B., Seismotectonics and rupture process of the M W 7.1 2011 Van reverse-faulting earthquake, eastern Turkey, and implications for hazard in regions of distributed shortening, Geophys. J. Int., 2016, vol. 206, pp. 501–524. https://doi.org/10.1093/gji/ggw158
Mescherikov, J.A., Resent crustal movements in seismic regions: Geodetic and geomorphic data, Tectonophysics, 1968, vol. 6, pp. 29–39. https://doi.org/10.1016/0040-1951(68)90024-3
Ozener, H., Dogru, A., and Unlutepe, A., An approach for rapid assessment of seismic hazards in Turkey by continuous GPS data, Sensors, 2009, vol. 9, no. 1, pp. 602–615. https://doi.org/10.3390/s90100602
Özkaymak, Ç., Sözbilir, H., Bozkurt, E., Dirik, K., Topal, T., Alan, H., Çağlan, D., 23 Ekim 2011 Tabanlı-Van Depreminin Sismik Jeomorfolojisi ve Doğu Anadolu’daki Aktif Tektonik Yapılarla Olan İlişkisi, J. Geol. Eng., 2011, vol. 35, no. 2, pp. 175–200.
Rodkin, M.V. and Kaftan, V.I., Post-seismic relaxation from geodetic and seismic data, Geod. Geodyn., 2017, vol. 8, no. 1, pp. 13–16. https://doi.org/10.1016/j.geog.2017.01.001
Roeloffs, E.A., Evidence for aseismic deformation rate changes prior to earthquakes, Annu. Rev. Earth Planet. Sci., 2006, vol. 34, pp. 591–627. https://doi.org/10.1146/annurev.earth.34.031405.124947
Şengör, A.M.C., Ozeren, S., Zor, E., and Genç, T., East Anatolian high plateau as a mantle-supported, N-S shortened domal structure, Geophys. Res. Lett., 2003, vol. 30, no. 24, Paper ID 8045. https://doi.org/10.1029/2003GL017858
Tiryakioğlu, I., Yavasoğlu, H., Uğur, M.A., Özkaymak, Ç., Yilmaz, M., Kocaoğlu, H., and Turgut, B., Analysis of October 23 (Mw 7.2) and November 9 (Mw 5.6), 2011 Van earthquakes using long-term GNSS time series, Earth Sci. Res. J., 2017, vol. 21, no. 3, pp. 147–156. https://doi.org/10.15446/esrj.v21n3.62812
Toker, M., Şengör, A.M.C., Schluter, F.D., Demirbağ, E., Çukur, D., İmren, C., and Niessen, F., The structural elements and tectonics of the Lake Van basin (Eastern Anatolia) from multi-channel seismic reflection profiles, J. Afr. Earth Sci., 2017, vol. 129, pp. 165–178. https://doi.org/10.1016/j.jafrearsci.2017.01.002
Wang, C., Ding, X., Li, Q., Shan, X., Zhu, W., Guo, B., and Liu, P., Coseismic and postseismic slip models of the 2011 Van earthquake, Turkey, from InSAR, offset-tracking, MAI, and GPS observations, J. Geodyn., 2015, vol. 91, pp. 39–50. https://doi.org/10.1016/j.jog.2015.08.006
Wu, J.C., Tang, H.W., and Chen, Y.Q., Effects of triangle shape factor on precision of crustal deformation calculated, J. Geodesy Geodyn., 2003, vol. 23, pp. 26–30.
Wu, J.C., Tang, H.W., Chen, Y.Q., and Li, Y.X., The current strain distribution in the North China Basin of eastern China by least-squares collocation, J. Geodyn., 2006, vol. 41, pp. 462–470. https://doi.org/10.1016/j.jog.2006.01.003
Zor, E., Sandvol, E., Gurbuz, C., Turkelli, N., Seber, D., and Barazangi, M., The crustal structure of the East Anatolian plateau (Turkey) from receiver functions, Geophys. Res. Lett., 2003, vol. 30, no. 24, Paper ID 8044. https://doi.org/10.1029/2003GL018192
ACKNOWLEDGMENTS
We are grateful to the reviewers for their valuable comments.
Funding
The study was carried in partial fulfillment of state contract of the Geophysical Center of the Russian Academy of Sciences approved by the Ministry of Science and Higher Education of the Russian Federation.
Author information
Authors and Affiliations
Corresponding authors
Additional information
Translated by M. Nazarenko
Supplementary Information
Rights and permissions
About this article
Cite this article
Kaftan, V.I., Kaftan, I. & Gök, E. Crustal Movements and Deformations in Eastern Turkey in Connection with the Van Earthquake (October 23, 2011, Мw = 7.2): Study from GPS Data. Izv., Phys. Solid Earth 57, 319–331 (2021). https://doi.org/10.1134/S1069351321030071
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S1069351321030071