Abstract
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We describe a 3-D time-domain, displacement-based, finite-difference elastic wave modeling algorithm that is constructed by defining the material properties within cubes. In the conventional displacement-based finite-difference method, both displacements and material properties are defined at the nodal points, whereas in our finite-difference algorithm, displacements are still assigned to the nodal points but material properties are defined within cubes. In this case, free-surface boundary conditions, which describe stress-free at the free surface, are naturally satisfied by the changes of material properties. Through numerical examples for infinite homogeneous and semi-infinite homogeneous models, we could examine the accuracy of the 3-D finite-difference elastic wave modeling algorithm. Some numerical examples showed that the 3-D finite-differenc elastic wave modeling algorithm satisfies the reciprocity theorem and successfully generates synthetic seismograms and snapshots.
시간영역에서 변위만을 이용하여 수행되는 3차원 변위근사 유한차분 탄성파 모델링에서 자유면 경계조건을 정확히 묘사하기 위한 방법으로 육면체 내부에 매질의 물성을 정의할 것을 제안한다. 매질의 물성과 변위를 모두 격자점에 정의하는 기존의 방법과는 달리, 매질의 물성을 육면체 내부에 정의할 경우 추가적인 자유면 경계조건을 사용하지 않고도 매질의 물성의 변화만으로 자유면에서 응력이 사라진다는 자유면 경계조건을 만족시킬 수 있다. 무한 균질 매질과 반무한 균질 매질에 대하여 수치적인 해와 해석적인 해를 비교함으로써 육면체 내부에 매질의 물성을 정의하는 3차원 유한차분 탄성파 모델링법의 정확성을 확인하였다. 송신원과 수진기의 위치가 서로 바뀐 경우에 대하여 수치적으로 구한 해들을 비교함으로써 육면체 내부에 매질의 물성을 정의하는 3차원 유한차분 탄성파 모델링 알고리듬이 상반원리 (reciprocity theorem)를 만족시킨다는 것을 알 수 있었다. 또한, 수평층 구조 및 단층구조에 대하여 합성탄성파 단면도 및 스냅단면도를 성공적으로 작성할 수 있었다.
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- Publisher :The Korean Society of Mineral and Energy Resources Engineers
- Publisher(Ko) :한국자원공학회
- Journal Title :Journal of the Korean Society for Geosystem Engineering
- Journal Title(Ko) :한국지구시스템공학회지
- Volume : 43
- No :1
- Pages :65-75


Journal of the Korean Society of Mineral and Energy Resources Engineers







