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Hypocentral Depth Determination of Gyeongju Earthquake Aftershock Sequence

경주 지진 여진의 진원 깊이 연구

  • Chung, Tae Woong (Department of Energy & Mineral Resources Engineering, Sejong University) ;
  • Iqbal, Muhammad Zafar (Department of Energy & Mineral Resources Engineering, Sejong University)
  • Received : 2016.12.30
  • Accepted : 2017.02.21
  • Published : 2017.02.28

Abstract

Hypocentral depths of 103 aftershocks of the 12 September 2016 Gyeongju earthquake (ML 5.8) were inverted by epicentral relocation, using HYPO71 and HYPOINVERSE. From the comparison of seven models that reflect regional velocity structure in the southern Korean Peninsula, HYPO71 with linear weighting over the whole range showed less residuals than HYPOINVERSE for the model near the epicenter. Less uncertainties of focal depths were observed for the events with large magnitude and short range of the closest S-phase distance.

Acknowledgement

Supported by : 기상산업진흥원

References

  1. Asep, N. R., and Chung, T. W., 2016, Depth dependent crustal scattering attenuation revealed by using single or few events in South Korea, Bull. Seismol. Soc. Am., 106, 1499-1508. https://doi.org/10.1785/0120150351
  2. Asep, N. R., Chung, T. W., Yoshimoto, K., and Son, B., 2015, Separation of intrinsic and scattering attenuation using single event source in South Korea. Bull. Seismol. Soc. Am., 105,858-872. https://doi.org/10.1785/0120140259
  3. Chang, S.-J., and Baag, C.-E., 2006, Crustal structure in southern Korea from joint analysis of regional broadband waveforms and travel times. Bull. Seismol. Soc. Am., 96, 856-870. https://doi.org/10.1785/0120040165
  4. Cho, H.-M., Baag, C.-E., Lee, J. M., Moon, W. M., Jung, H., Kim, K. Y., and Asudeh, I., 2006, Crustal velocity structure across the southern Korean Peninsula from seismic refraction survey. Geophys. Res. Lett., 33, L06307.
  5. Cho, H.-M., Baag, C.-E., Lee, J. M., Moon, W. M., Jung, H., and Kim, K. Y., 2013, P and S-wave velocity model along crustal scale refraction and wide-angle reflection profile in the southern Korean peninsula, Tectonophysics, 582, 84-100. https://doi.org/10.1016/j.tecto.2012.09.025
  6. Chung, M.-K., and Kyung, J. B., 2013, Source characteristics of the recent earthquakes for seven years in the southwestern region of the Korean Peninsula, J. Korean Earth Sci. Soc., 34, 59-68. https://doi.org/10.5467/JKESS.2013.34.1.59
  7. Chung, T. W., and Asep, N. R., 2014, Multiple lapse time window analysis of the Korean Peninsula with considering focal depth, Geophys. and Geophys. Explor., 16, 293-299.
  8. Gomberg, J. S., Shedlock, K. M., and Roecker, S. W., 1990, The effect of S-wave arrival times on the accuracy of hypocenter estimation, Bull. Seismol. Soc. Am., 80, 1605-1628.
  9. Kim, K.-H., Kang, T.-S., Rhie, J., Kim, Y.-H., Park, Y., Kang, S.Y., Han, M., Kim, J., Park, J., Kim, M., Kong, C. H., Heo, D.,Lee, H., Park, E., Park, H., Lee, S.-J., Cho, S., Woo, J.-U., Lee, S.-H., and Kim, J., 2016, The 12 September 2016 Gyeongju earthquakes: 2. Temporary seismic network for monitoring aftershocks, Geosciences Journal, 20, 753-757. https://doi.org/10.1007/s12303-016-0034-9
  10. Klein, F. W., 2002, User's guide to HYPOINVERSE-2000, a Fortran program to solve for earthquake locations and magnitudes, U. S. Geolological Survey Open-File Report 02-171, 123 p.
  11. Lee, W. H. K., and Lahr J. C., 1975, HYP071 (Revised): A computer program for determining hypocenter, magnitude, and first motion pattern of local earthquakes, U. S. GeologicalSurvey Open File Report 75-311, 113 p.
  12. Liernert, B. R., Berg, E., and Frazer, L. N., 1986, HYPOCENTER: An earthquake location method using centered, scaled, and adaptively least squares, Bull. Seismol. Soc. Am., 76, 771-783.
  13. Omuralieva, A. M., Hasegawa, A., Matsuzawa, T., Nakajima, J.,and Okada, T., 2012, Lateral variation of the cutoff depth of shallow earthquakes beneath the Japan island and its implication for seismogenesis, Tectonophysics, 518-521, 93-105. https://doi.org/10.1016/j.tecto.2011.11.013
  14. Saikia, U., Rai, S. S., Subrahmanyam, M., Dutta, S., Bose, S.,Borah, K., and Meena, R., Accurate location and focal mechanismof small earthquakes near Idukki Reservoir, Kerala: implication for earthquake genesis, Current Science, 107,1885-1891.
  15. Wadati, K., 1933, On the travel time of earthquake waves (part II), Geophysical Magazine, 7, 101-111.

Cited by

  1. Deep Fault Plane Revealed by High‐Precision Locations of Early Aftershocks Following the 12 September 2016 ML 5.8 Gyeongju, Korea, Earthquake vol.108, pp.1, 2018, https://doi.org/10.1785/0120170104
  2. Temporal and Spatial Variations of the M<sub>L</sub> 5.8 Gyeongju Earthquake on September 12, 2016 vol.39, pp.4, 2018, https://doi.org/10.5467/JKESS.2018.39.4.342