Geophysics and Geophysical Exploration (지구물리와물리탐사)

Korean Society of Earth and Exploration Geophysicists (한국지구물리·물리탐사학회)
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Automatic Velocity Analysis by using an High-resolution Bootstrapped Differential Semblance Method

고해상도 Bootstrapped Differential Semblance를 이용한 자동 속도분석

  • Choi, Hyungwook (Dept. of Natural Resources and Geoenvironmental Engineering, Hanyang Univ.) ;
  • Byun, Joongmoo (Dept. of Natural Resources and Geoenvironmental Engineering, Hanyang Univ.)
  • 최형욱 (한양대학교 자원환경공학과) ;
  • 변중무 (한양대학교 자원환경공학과)
  • Received : 2013.09.06
  • Accepted : 2013.11.14
  • Published : 2013.11.30
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Abstract

The accuracy of the automatic NMO velocity analysis, which is used for an effective and objective NMO velocity analysis, is highly affected by the velocity resolution of the velocity spectrum. In this study, we have developed an automatic NMO velocity algorithm, where the velocity spectra are created using high-resolution bootstrapped differential semblance (BDS), and the velocity analysis on CMP gathers is performed in parallel with MPI. We also compared the velocity models from the developed automatic NMO velocity algorithm with high-resolution BDS to those from BDS. To verify the developed automatic velocity analysis module we created synthetic seismic data from a velocity model including horizon layers. We confirmed that the developed automatic velocity analysis module estimated velocity more accurately. In addition, NMO velocity which yielded a CMP stacked section, where the coherency of the events were improved, was estimated when the developed module was applied to a marine field data set.

효율적이고 객관적인 NMO 속도분석을 위해 사용되는 자동 속도분석의 정확성은 속도 빛띠의 속도 해상도에 많은 영향을 받는다. 본 연구에서는 고해상도 BDS (high-resolution Bootstrapped Differential Semblance)를 이용하여 속도 빛띠를 구성하고, 이를 이용하여 공통 중간점 모음 별로 병렬적으로 자동 속도분석을 수행하는 모듈을 개발하였다. 또한 이 고해상도 BDS를 이용하는 자동 속도분석 모듈의 속도분석 결과를 BDS (Bootstrapped Differential Semblance)를 이용한 자동 속도분석의 결과와 비교하였다. 수평층을 포함한 속도모델로부터 얻은 합성 탄성파 탐사자료를 생성하고 이를 이용하여 개발된 모듈을 검증한 결과 본 연구를 통해 개발된 모듈이 좀 더 정확한 속도를 추정하는 것을 확인하였다. 또한 현장자료에 개발된 모듈을 적용하여 이벤트의 연속성이 향상된 공통 중간점 겹쌓기 단면을 구할 수 있는 NMO 속도를 추정하였다.

Keywords

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