지구물리와물리탐사 (Geophysics and Geophysical Exploration)

  • 제20권4호
  • /
  • Pages.199-206
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  • 2017
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  • 1229-1064(pISSN)
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  • 2384-051X(eISSN)
한국지구물리·물리탐사학회 (Korean Society of Earth and Exploration Geophysicists)
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직접파를 이용한 배경매질 유속정보 도출과 유속을 고려한 파형역산의 적용

Extraction of Flow Velocity Information using Direct Wave and Application of Waveform Inversion Considering Flow Velocity

  • 이다운 (한국해양대학교 해양에너지자원공학과) ;
  • 정우근 (한국해양대학교 에너지자원공학과) ;
  • 신성렬 (한국해양대학교 에너지자원공학과) ;
  • 배호석 (국방과학연구소 제 6기술연구본부)
  • Lee, Dawoon (Department of Ocean Energy and Resources Engineering, Korea Maritime and Ocean University) ;
  • Chung, Wookeen (Department of Energy Resources Engineering, Korea Maritime and Ocean University) ;
  • Shin, Sungryul (Department of Energy Resources Engineering, Korea Maritime and Ocean University) ;
  • Bae, Ho Seuk (The 6th R&D Institute, Agency for Defense Development)
  • 투고 : 2017.07.12
  • 심사 : 2017.10.08
  • 발행 : 2017.11.30
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초록

해상탐사에서 얻어지는 현장자료는 바람, 파도, 조류, 배경매질의 유속 등 다양한 환경요소에 영향을 받는다. 배경매질의 유속을 제외한 대부분의 환경요소는 자료처리 단계에서 적절한 보정이 이루어지고 있다. 본 연구에서는 배경매질의 유속정보가 파형역산에 미치는 영향을 분석하기 위해 배경매질의 유속정보를 고려하는 파동 방정식 모델링을 활용하여 관측자료를 생성하고, 생성된 자료를 통해 수치 실험을 진행하였다. 수치예제에는 다소 비현실적인 유속이 적용된 결과도 포함되어 있다. 이와 더불어, 탐사자료의 유속정보를 수치적 기법으로 도출하여 역산을 수행하는 알고리즘을 제안하였다. 제안된 알고리즘은 수정된 Marmousi2 모델에 적용하여 유속에 따른 결과를 얻고자 하였다. 기존의 유속을 고려하지 않은 역산 결과와 제안된 알고리즘으로 수행한 역산 결과 비교를 통해 유속의 세기가 갱신되는 물성정보에 미치는 영향을 확인하였다.

Field data obtained from marine exploration are influenced by various environmental factors such as wind, waves, tidal current and flow velocity of a background medium. Most environmental factors except for the flow velocity are properly corrected in the data processing stage. In this study, the wave equation modeling considering flow velocity is used to generate observation data, and numerical experiments using the observation data were conducted to analyze the effect of flow velocity on waveform inversion. The numerical examples include the results with unrealistic flow velocities. In addition, an algorithm is suggested to numerically extract flow velocity for waveform inversion. The proposed algorithm was applied to the modified Marmousi2 model to obtain the results depending on the flow velocity. The effect of flow velocity on updated physical properties was verified by comparing the inversion results without considering flow velocity and those obtained from the proposed algorithm.

키워드

참고문헌

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