한반도 Lg파 감쇠상수 도출을 위한 한일 지진자료의 RTSM 적용에 대한 연구

The study of Reversed Two Station Method on Korea-Japan Seismic Data to Obtain Lg Attenuation of Korean Peninsula

  • 정태웅 (세종대학교 지구환경과학과)
  • 발행 : 2008.11.30

초록

일본, 중국 등 인접 지진다발 국가에서 큰 지진동이 전파되어 오는 경우, Lg파가 최대 진폭을 갖게 되어 Lg파의 감쇠상수$(Q^{-1})$는 매우 중요한 의미를 갖게 된다. RTSM에서 보다 신뢰성있는 $Q^{-1}$값은 긴 관측점간 혹은 진원간 거리에서 얻어지므로 남한 지역의 지진의 국내관측망 및 일본 큐슈지방을 중심으로 한 일본 지진관측망 자료를 이용하였다. 그러나, 본 해석결과는 현재의 조구조 상황과 달리 한반도의 $Q^{-1}$ 값이 매우 높게 산출되었다. 이는 감쇠상수가 큰 일본 지역의 부지영향인 것으로 추정된다.

Lg amplitude decrease $Q^{-1}$ is very important because the Lg phase is the largest seismic phase in Korea if hazardous earthquakes occurred at neighbor nations such as Japan and China. Since reliable $Q^{-1}$ from two station method can be obtained by long pair distance of stations or events, we used seismic stations both Korea and Japans recording Korean events. The obtained $Q^{-1}$ values, however, were anomalously high; these misguided values, inconsistent with tectonic activity of Korean Peninsula, seems to be related with high $Q^{-1}$ values of Japan region.

키워드

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