Geophysics and Geophysical Exploration (지구물리와물리탐사)

Korean Society of Earth and Exploration Geophysicists (한국지구물리·물리탐사학회)
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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
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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.

2016년 9월 12일 경주지진(규모 5.8)의 103개 여진의 진원 깊이를 HYPO71과 HYPOINVERSE를 이용한 진원 재결정을 통하여 역산하였다. 한반도에서 지역에 따라 변화하는 속도를 나타내는 7개 모델을 비교한 분석에서 전구간 선형가중치를 둔 HYPO71이 HYPOINVERSE에 비해 진앙 부근 모델이 잔차가 더 적은, 바람직한 결과를 얻었다. 규모가 큰 지진과 S파 진앙거리가 짧은 지진자료는 진원깊이 불확실성이 비교적 작게 관찰되었다.

Keywords

References

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  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