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Spatial and temporal variations of the aftershock sequences of the 1999 İzmit and Düzce earthquakes
Earth, Planets and Space volume 56, pages 933–944 (2004)
Abstract
In this study the properties of the aftershock sequences in the first five months after the 17 August 1999 İzmit and 12 November 1999 Düzce earthquakes are investigated. For this purpose, the b-value of frequency-magnitude distribution of earthquakes and temporal decay rate of aftershocks as described by the p-value in the modified Omori law are calculated. The data taken from the website of the KOERI consist of 1841 events for the İzmit and 913 events for the Düzce activity, respectively. The b-value for the İzmit sequence is found as 1.10±0.03 with Mc = 2.6 and b = 1.16 ± 0.05 for the Düzce sequence with Mc = 2.8. Both b-values are close to 1 and typical for aftershock sequences. The p-values are calculated as 0.86 ± 0.05 for the İzmit and p = 1.34 ± 0.09 for Düzce aftershocks, respectively. Small p-value found in İzmit sequence may be a result of the background seismicity of the aftershock region. Because of the lower p-value for the İzmit activity than that of the Düzce sequence, the aftershocks show a relatively slow decay rate in the İzmit earthquake. Considerable spatial variability is found, b-values ranging from 0.8 to 1.6, and p-values ranging from 0.4 to 1.4. The spatial variations of b and p-values of an aftershock sequence may associate with the rupture mechanism and geological structure of an earthquake area. A good agreement between the slip and b-value for the Düzce sequence are found whereas we could not observe a linear relation between these parameters for the İzmit sequence. After the İzmit earthquake, the larger b-values correlate with the regions where the lower stress changes occurred whereas the lower b-values are in the areas with the larger stress variations. Also, the lower and higher b-values are related to the higher and lower P-wave velocity in general. Regarding the geological aspect, the larger b and p-values for the two sequences are related to Holocene alluvium structures which have low velocity. On the other hand, after the both earthquakes, the larger p-values correlate well with the regions on which the maximum slip is located and the lower p-values are related to the lower slip regions. However, the material properties seem more effective than the stress changes and slip distributions in the b-value variations and the slip distribution is the most significant factor on p-values in the both sequences.
References
Aki, K., Maximum likelihood estimate of b in the formula log N = a - bM and its confidence limits, Bull. Earthquake Res. Inst., Tokyo Univ., 43, 237–239, 1965.
Akyuz, H. S., R. Hartleb, A. Barka, E. Altunel, G. Sunal, B. Meyer, and R. Armijo, Surface rupture and slip distribution of the 12 November 1999 Düzce Earthquake (M7.1) North Anatolian Fault, Bolu, Turkey, Bull. Seismol. Soc. Am., 92, 61–66, 2002.
Armijo, R., B. Meyer, S. Navarro, G. King, and A. Barka, Asymmetric slip partitioning in the sea of Marmara pull-apart: A clue to propagation processes of the North Anatolian Fault?, Terra Nova, 14, 80–86, 2002.
Aydin, A. and D. Kalafat, Surface ruptures of the 17 August and 12 November 1999 İzmit and Düzce earthquakes in northwestern Anatolia, Turkey: Their tectonic and kinematics significance and the associated damage, Bull. Seismol. Soc. Am., 92, 95–106, 2002.
Barka, A., H. S. Akyüz, E. Altunel, G. Sunal, Z. Çakır, A. Dikbaş, B. Yerli, R. Armijo, B. Meyer, J. B. de Chabalier, T. Rockwell, J. R. Dolan, R. Hartleb, T. Dawson, S. Christofferson, A. Tucker, T. Fumal, R. Langridge, H. Stenner, W. Lettis, J. Bachhuber, and W. Page, The surface rupture and slip distribution of the 17 August 1999 İzmit earthquake (M7.4), North Anatolian Fault, Bull. Seismol. Soc. Am., 92, 43–60, 2002.
Bürgmann, R., M. E. Ayhan, E. J. Fielding, T. J. Wright, S. McClusky, B. Aktuğ, C. Demir, O. Lenk, and A. Türkezer, Deformation during the 12 November 1999 Düzce, Turkey, earthquake, from GPS and InSAR data, Bull. Seismol. Soc. Am., 92, 161–171, 2002.
Eaton, J., M. O’Neil, and J. Murdock, Aftershocks of the 1966 Parkfield-Cholame, California, earthquake: A detailed study, Bull. Seismol. Soc. Am., 60, 1151–1197, 1970.
Enescu, B. and K. Ito, Spatial analysis of the frequency-magnitude distribution and decay rate of aftershock activity of the 2000 Western Tottori earthquake, Earth Planets Space, 54, 847–859, 2002.
Frohlich, C., Aftershocks and temporal clustering of deep earthquakes, J. Geophys. Res., 92, 13,944–13,956, 1987.
Frohlich, C. and S. Davis, Teleseismic b-values: Or, much ado about 1.0, J. Geophys. Res., 98, 631–644, 1993.
Guo, Z. and Y. Ogata, Statistical relation between the parameters of aftershocks in time, space, and magnitude, J. Geophys. Res., 102(B2), 2857–2873,1997.
Gülen, L., A. Pınar, D. Kalafat, N. Özel, G. Horasan, M. Yılmazer, and A. M. Işıkara, Surface fault breaks, aftershocks distribution, and rupture process of the 17 August 1999 İzmit, Turkey, earthquake, Bull. Seismol. Soc. Am., 92, 230–244, 2002.
Gutenberg, R. and C. F. Richter, Frequency of earthquakes in California, Bull. Seismol. Soc. Am., 34, 185–188, 1944.
Hirata, T., Aftershock sequence of the earthquake off Shikotan Island on January 29, 1968, Geophys. Bull. Hokkaido Univ., 21, 33–43, 1969 (in Japanese).
Ito, A., B. Üçer, Ş. Barış, A. Nakamura, Y Honkura, T. Kono, S. Hori, A. Hasegawa, R. Pektaş, and S. M. Işıkara, Aftershock activity of the 1999 İzmit, Turkey, Earthquake Revealed from microearthquake observations, Bull. Seismol. Soc. Am., 92, 418–427
Kagan, Y. Y. and L. Knopoff, Stochastic synthesis of earthquake catalogs, J. Geophys. Res., 86, 2853–2862, 1981.
King, C. P., G. A. Hubert-Ferrari, S. S. Nalbant, B. Meyer, R. Armijo, and D. Bowman, Coulomb interactions and the 17 august 1999 Izmit, Turkey earthquake, Earth and Planetary Science, 333, 557–569, 2001.
Kisslinger, C. and L. M. Jones, Properties of aftershock sequences in Southern California, J. Geophys. Res., 96(B7), 11,947–11,958, 1991.
Nakamura, A., A. Hasegawa, A. Ito, B. Üçer, Ş. Barış, Y. Honkura, T. Kono, S. Hori, R. Pektaş, T. Komut, C. Çelik, and A. M. Işıkara, P-wave velocity structure of the crust and its relationship to the occurrence of the 1999 İzmit, Turkey, earthquake and aftershocks, Bull. Seismol. Soc. Am., 92, 330–338, 2002.
Ogata, Y., Estimation of parameters in the modified Omori formula for aftershock frequencies by the maximum likelihood procedure, J. Phys. Earth, 31, 115–124, 1983.
Ogata, Y, M. Imoto, and K. Katsura, 3-D spatial variation of b-values of magnitude-frequency distribution beneath the Kanto District, Japan, Geophys. J. Int., 104, 138–146, 1991.
Olsson, R., An estimation of the maximum b-value in the Gutenberg-Richter relation, Geodynamics, 27, 547–552, 1999.
Özalaybey, S., M. Ergin, M. Aktar, C. Tapırdamaz, F Biçmen, and A. Yörük, The 1999 İzmit earthquake sequence in Turkey: Seismological and tectonic aspects, Bull. Seismol. Soc. Am., 92, 376–386, 2002.
Parsons, T., S. Toda, R. S. Stein, A. Barka, and J. H. Dieterich, Heightened odds of large earthquakes near İstanbul: An interaction-based probability calculation, Science, 288, 661–665, 2000.
Polat, O., H. Eyidoğan, H. Haessler, A. Cisternas, and H. Philip, Analysis and interpretation of aftershock sequence of the August 17, 1999, İzmit (Turkey) earthquake, Journal of Seismology, 6, 287–306, 2002a.
Polat, O., H. Haessler, H. A. Cisternas, H. Philip, H. Eyidoğan, M. Aktar, M. Frogneux, D. Comte, and C. Gürbüz, The İzmit (Kocaeli) earthquake of 17 August 1999: Previous seismicity, aftershocks, and seismotectonics, Bull. Seismol. Soc. Am., 92, 361–375, 2002b.
Scholz, C. H., The Mechanics of Earthquakes and Faulting, Cambridge Univ. Press, Cambridge, 439 pp, 1990.
Utsu, T., Aftershocks and earthquake statistics (I): Some parameters which characterize an aftershock sequence and their interrelations, J. Faculty Sci., Hokkaido University, Ser VII (Geophys.), 3, 129–195, 1969.
Utsu, T., 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), J. Faculty Sci., Hokkaido University, Ser VII (Geophys.), 3, 379–441, 1971.
Utsu, T., Y. Ogata, and R. S. Matsu’ura, The centenary of the Omori formula for decay law of aftershock activity, J. Phys. Earth, 43, 1–33, 1995.
Wiemer, S. and K. Katsumata, Spatial variability of seismicity parameters in aftershock zones, J. Geophys. Res., 104(B6), 13,135–13,151, 1999.
Wiemer, S. and M. Wyss, Mapping the frequency-magnitude distribution in asperities: An improved technique to calculate recurrence times, J. Geophys. Res., 102, 15,115–15,128, 1997.
Wiemer, S. and M. Wyss, Minimum magnitude of completeness in earthquake catalogs: Examples from Alaska, the Western United States, and Japan, Bull. Seismol. Soc. Am., 90, 859–869, 2000.
Wiemer, S. and R. F. Zuniga, ZMAP-A software package to analyze seismicity (abstarct), EOS Trans. AGU, 75(43), Fall Meet. Suppl., 456, 1994.
Wiemer, S., S. R. McNutt, and M. Wyss, Temporal and three dimensional spatial analysis of the frequency-magnitude distribution near Long Valley Caldera, California, Geophys. J. Int., 134, 409–421, 1998.
Yagi, Y and M. Kikuchi, Preliminary results of rupture process for the November 12, 1999 Turkey earthquake, http://wwweic.eri.u-tokyo.ac.jp/yuji/trk2/Turkeyafter.html, 199
Yagi, Y and M. Kikuchi, Source rupture process of Kocaeli, Turkey, earthquake of August 17, 1999, obtained by joint inversion of near-field data and teleseismic data, Geophys. Res. Lett., 27, 1969–1972, 2000.
Yamakawa, N., Foreshocks, aftershocks, and earthquake swarms (IV)-Frequency decrease of aftershocks in its initial and later stages, Pap. Met. Geophys., 19, 109–119, 1968.
Young, R. P. and S. C. Maxwell, Seismic characterization of a highly stressed rock mass using tomographic imaging and induced seismicity, J. Geophys. Res., 97, 12,361–12,373, 1992.
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Bayrak, Y., Öztürk, S. Spatial and temporal variations of the aftershock sequences of the 1999 İzmit and Düzce earthquakes. Earth Planet Sp 56, 933–944 (2004). https://doi.org/10.1186/BF03351791
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DOI: https://doi.org/10.1186/BF03351791