A Study on the Attenuation of High-frequency P and S Waves in the Crust of the Southeastern Korea using the Seismic Data in Deok-jung Ri

덕정리 지진자료를 이용한 한국남동부지역 지각의 P, S파 감쇠구조 연구

  • Chung, Tae-Woong (Department of Earth Sciences and Research Institute of Geoinformatics and Geophysics, Sejong University) ;
  • Sato, Haruo (Department of Geophysics, Graduate School of Science, Tohoku University)
  • Published : 20000900

Abstract

The attenuation characteristics($Q^{-1}$) are important factors representing the physical properties of the Earth interiors, and are essential for the quantitative prediction of strong ground-motion. Based on 156 earthquakes including 76 single-station record on the seismic station located Deok-jung Ri, southeastern Korea, we made the simultaneous measurement of P and S wave attenuation($Q_P^{-1}\;and\;Q_S^{-1}$) by means of extended coda-normalization method. Estimated $Q_P^{-1}\;and\;Q_S^{-1}$ decreased from $1{\times}10^{-2}\;and\;9{\times}10^{-3}$ at 1.5 Hz to $6{\times}10^{-4}\;and\;5{\times}10^{-4}$ at 24 Hz, respectively. This can be expressed by $Q_P^{-1}=0.01\;f^{-1.07}\;and\;Q_S^{-1}=0.01\;f^{-1.03}$ which indicate strong frequency dependence.

지진파가 전달되면 진폭이 감쇠되는 정도를 나타내는 감쇠상수 $Q^{-1}$는 지구내부 물질의 물리적 성질을 나타내는 중요한 척도이며, 구조물의 내진설계에 있어서 지반의 강진동을 정량적으로 예측하기 위해 필수적이다. 경상북도 덕정리에 위치한 지진관측기기에 기록된 80지진과 76단일 관측망 기록자료를 바탕으로 한국남동부의 P, S 실체파 감쇠상수를 Coda확장규격화법에 의해 구하였다. 구하여진 $Q_P^{-1}$$Q_S^{-1}$는 각각 1.5Hz에서 $1{\times}10^{-2}$$9{\times}10^{-3}$, 24 Hz에서 $6{\times}10^{-4}$$5{\times}10^{-4}$로 줄어들고, $Q_P^{-1}=0.01\;f^{-1.07}$$Q_S^{-1}=0.01\;f^{-1.03}$의 강한 주파수 의존성을 보였다.

Keywords

References

  1. Proceeding of EESK Conference-Spring 1999 경상분지에서의 Coda파의 감쇠특성 김성균;김복희
  2. 지질학회지 v.35 경상분지에서의 P파 감쇠 김성균;전명순;김준경
  3. 한반도 지짙파 에너지감쇠 연구, 한국원자력연구소 보고서, KAERI-96-08 박창업
  4. 지구물리 v.1 한반도의 역사지진자료 이기화
  5. 지진연구, 한국자원연구소 보고서, KR-94(C) 전명순;지헌철;전정수
  6. 한국지구과학회지 한국남동부 지각의 P, S파 감쇠구조비교연구 정태웅
  7. 경상분지에서의 지진연구(III), 한국자원연구소보고서, KR-96(C)-4 지헌철;전정수;신인철
  8. 활성단층 조사평가연구-한반도 동남부지역, 한국자원연구소 보고서, KR-98(C)-22 최위찬;이동영;이봉주;류충렬;최범영;최성자;조등룡;김주용;이창범;기원서;양동윤;김인준;김유숙;유장한;채병곤;김원영;강필종;유일현;이희권
  9. Journal of Geophysical Research v.100 Earthquake source scaling relationship from -1 to 5 ML using seismograms recorded at 2.5-km depth Abercrombie, R.E.
  10. Physics of the Earth Planetary Interiors v.21 Attenuation of shear waves in the lithosphere for frequencies from 0.05 to 25Hz Aki, K.
  11. Cretaceous strata, in Geology of Korea Chang, K.H.;Lee, D.S.(ed.)
  12. Bulletin of the Seismological Society of America v.77 A novel technique for measuring Lgattenuation: results from Eastern Canada between 1 to 10 Hz Chun, K.Y.;West, G.F.;Kokoski, R.J.;Samson, C.
  13. Bulletin of the seismological Society of america v.72 The effects of attenuation and site response on the spectra of microearthquakes in the northeastern Caribbean Frankel, A.
  14. Journal of Geophysical Research v.95 Attenuation of high-frequency shear waves in the crust: measurements from New York State, South Africa and Southern California Frankel, A.;McGarr, A.;Bicknell, J.;Mori, J.;Seeber, L.;Cranswick, E.
  15. Spectral Analysis Hino, M.
  16. J. Geol. Soc. Korea v.20 A geophysical study of the Yangsan Fault area Lee, K.;Jeong, B.I.;Kim, Y.H.;Yang, S.J.
  17. Journal fo the Geological Society of Korea v.27 Segmentation of the Yangsan fault system: Geophysical studies on majour faults in the Kyeongsang basin Lee, K.;Jin, Y.G.
  18. Proceedings of EESK Conference Q estimates using the coda waves in the Kyungsang Basin Lee, W.S.;Lee, K.
  19. Bulletin of the Seismological Society of America v.72 Experimental study of the spectral content for shallow earthquakes Modiano, T.;Hatzfeld, D.
  20. Seismic wave propagation and scattering in the heterogeneous earth Sato, H.;Fehler, M.C.
  21. Metallogeny of an Andean type continental margin in South Korea, implications for opening of the Japan Sea, in Island Arcs, Deep Sea Trenches and Back Arc Basins, Maurice Ewing Ser., Vol. 1 Sillitoe, R.H.;Talwani, M.(ed.);Pitman, W.C. III(ed.)
  22. Bulletine of the Earthquake Research Institute, University of Tokyo v.53 Spectral analysis of the coda waves from local earthquakes Tsujiura, M.
  23. Zisin v.20 Determination of earthquake magnitude from duration of oscillation Tsumura, K.
  24. Bulletine of the Earthquake Research Institute, University of Tokyo v.45 Determination of earthquake magnitude from total duration of oscillation Tsumura, K.
  25. Geophysical Journal International v.114 Frequency-dependent attenuation of P and S waves in the Kanto area, Japna, based on the codanormalization method Yoshimoto, K.;Sato, H.;Ohtake, M.
  26. Pure Applied Geophysics v.153 Frequency-dependent attenuation of high-frequency P and S waves in the upper crust in western Nagano, Japan Yoshimoto, K.;Sato, H.;Ito, Y.;Ito, H.;Ohminato, T.;Ohtake, M.