AVO analysis on BSR in the northern regions of the South Shetland Islands, Antarctica

남극 남쉐틀랜드 북부지역에서 나타나는 BSR의 AVO 반응분석

  • 구경모 (한국해양연구원 부설 극지연구소) ;
  • 홍종국 (한국해양연구원 부설 극지연구소) ;
  • 진영근 (한국해양연구원 부설 극지연구소) ;
  • 이주한 (한국해양연구원 부설 극지연구소) ;
  • 이정모 (경북대학교)
  • Published : 2007.06.07

Abstract

Geophysical survey has been conducted on the continental margin off the South Shetland Islands aboard R/V Onnuri of KORDI in 1992/1993. About 800-line km of 96-channel reflection data have been acquired. On the seismic section, BSR with strong reflectivity and negative polarity has been found at 700 ms below the sea bottom. BSR is considered as the base of gas hydrates and AVO analysis was performed to study physical properties along BSR. True amplitude recovery and surface consistence amplitude were applied to seismic data and angle gathers were obtained. AVO gradient and AVO intercept are calculated on every CDP gather. Section of AVO intercept show strong reflectivity and negative polarity on BSRs and stronger continuity of BSR than stacked section. Cross plot of intercept-gradient indicates that the lower layer below BSR is filled with free gas.

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