Elastic Wave Modeling Including Surface Topography Using a Weighted-Averaging Finite Element Method in Frequency Domain

지형을 고려한 주파수 영역 가중평균 유한요소법 탄성파 모델링

  • Choi, Ji-Hyang (Dept. of Energy System Eng., Seoul National University) ;
  • Nam, Myung-Jin (Dept. of Petroleum and Geosystems Eng., The University of Texas at Austin, Groundwater and Geothermal Div., Korea Institute of Geoscience and Mineral Resources) ;
  • Min, Dong-Joo (Dept. of Energy System Eng., Seoul National University) ;
  • Shin, Chang-Soo (Dept. of Energy System Eng., Seoul National University) ;
  • Suh, Jung-Hee (Dept. of Civil, Urban and Geosystem Eng., Seoul National University)
  • 최지향 (서울대학교 에너지시스템공학부) ;
  • 남명진 (한국지질자원연구원 지하수지열연구부) ;
  • 민동주 (서울대학교 에너지시스템공학부) ;
  • 신창수 (서울대학교 에너지시스템공학부) ;
  • 서정희 (서울대학교 지구환경시스템공학부)
  • Published : 2008.05.31

Abstract

Abstract: Surface topography has a significant influence on seismic wave propagation in a reflection seismic exploration. Effects of surface topography on two-dimensional elastic wave propagation are investigated through modeling using a weighted-averaging (WA) finite-element method (FEM), which is computationally more efficient than conventional FEM. Effects of air layer on wave propagation are also investigated using flat surface models with and without air. To validate our scheme in modeling including topography, we compare WA FEM results for irregular topographic models against those derived from conventional FEM using one set of rectangular elements. For the irregular surface topography models, elastic wave propagation is simulated to show that breaks in slope act as a new source for diffracted waves, and that Rayleigh waves are more seriously distorted by surface topography than P-waves.

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