A Study of the Comparison of the Shear Wave Velocity Profiles Obtained by a Surface Wave Exploration Method with Borehole Measurements

표면파 탐사 방법을 이용하여 구한 S파 속도와 시추결과의 비교 연구

  • Jung, Hee-Ok (Department of Ocean System Engineering, Kunsan National University)
  • 정희옥 (군산대학교 해양과학대학 해양시스템공학과)
  • Published : 2003.10.31

Abstract

Surface wave exploration method has many advantages over other conventional exploration methods. Only limited accumulation of the study results has been made due to the recent development of the method. In this study the characteristics of the phase dispersion curves of four sites with different geo-technical properties have been identified. A generalized inversion method was used to obtain the shear wave velocity profiles of the study areas. The shear wave velocity profiles were compared with the columnar sections of the boreholes at the sites. This study shows that the rapid changes in the shear wave velocities are consistent with the changes in the sedimentary or lithologic faces found in the borehole measurements. This implicates that the surface wave exploration method could be used to identify changes in the physical properties of sediments or rocks.

표면파 탐사는 탄성파를 이용한 여러 가지 다른 탐사 방법과 비교하여 독특한 장점들을 가지고 있다. 그러나 이 방법은 최근에 개발되기 시작하여 아직 연구 결과가 많이 축적되지 않은 분야이다. 이 연구에서는 지반 공학적 성질이 서로 다를 것으로 예상되는 여러 지역에서 표면파 탐사자료를 획득하여 그 분산곡선의 특징을 찾아보았다. 또한 분산곡선을 역산하여 S파 속도구조를 구하여 이를 시추조사 결과와 비교하였다. 그 결과 퇴적물상이나 암석상의 변화가 S파속도의 급격한 변화와 관련되어 있음을 확인하였다. 이것은 표면파 탐사법을 이용하여 퇴적물이나 암석의 물리적 성질이 급격하게 변화하는 경계면을 구별할 수 있는 가능성을 시사한다.

Keywords

References

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