지구물리와물리탐사 (Geophysics and Geophysical Exploration)

  • 제16권4호
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  • Pages.234-239
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  • 2013
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  • 1229-1064(pISSN)
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  • 2384-051X(eISSN)
한국지구물리·물리탐사학회 (Korean Society of Earth and Exploration Geophysicists)
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2011년 토호쿠 대지진의 수중음향 관측

Hydroacoustic Observation on the 2011 Tohoku Earthquake

  • 투고 : 2013.10.22
  • 심사 : 2013.11.15
  • 발행 : 2013.11.30
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초록

2011년 3월 11일에 일본 토호쿠 앞바다에서 규모 9.0의 대지진이 발생하였고 이는 전 세계 지진관측망뿐 아니라 IMS(International Monitoring System)에서 운영하는 하와이 수중음향 관측망에도 기록되었다. 우리는 이 대지진을 비롯한 두개의 규모 7 이상의 여진의 수중음향 자료에 대하여 방위각 및 스펙트럼 분석을 통해 복잡한 지진원에서 발생한 T 파의 특성을 파악하고자 연구를 수행하였다. 이를 통해 복잡한 단층 파열 현상이 직접적으로 T 파의 형태에 영향을 미치는 것을 관측하였고, 빠른 단층 파열 과정에 의하여 발생한 T 파가 중첩되는 구간에서 큰 에너지가 기록된 것을 확인할 수 있었다. 두 여진에서 발생한 T 파를 비교한 결과 단층 종류와 깊이에 의해 T 파의 형태와 주파수 특성이 변하는 것을 확인하였다.

The $M_W$ 9.0 thrust-fault earthquake has occurred in the Pacific coast of Tohoku, Japan, on March 11, 2011. We present the detection of the great earthquake and analyze T-waves associated with the main event and two other big aftershocks ($M_W$ > 7) recorded in a hydroacoustic array (H11N) in the Pacific Ocean by performing array and spectral analysis to examine characteristics of T-waves generated from the big events. The complex rupture process of the main event directly influences on the shape of the T-waves, and the peak locates on where T-waves excited from fast rupturing process arrive. We compare the two aftershocks with different fault type and show that the fault type and the source depth change shape and spectral contents of T-waves.

키워드

참고문헌

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피인용 문헌

  1. Analysis of Pressure and Acceleration Signals from the 2011 Tohoku Earthquake Observed by the DONET Seafloor Network vol.12, pp.1, 2017, https://doi.org/10.20965/jdr.2017.p0163
  2. Analysis of T-phase and Tsunami Signals Associated with the 2011 Tohoku Earthquake Acquired by CTBT Water-Column Hydrophone Triplets vol.72, pp.2, 2016, https://doi.org/10.2208/kaigan.72.I_337