Abstract
In seismic sections, the presence of a gas hydrate stability zone (GHSZ) is often marked by a bottom-simulating reflector, which has a negative polarity with respect to the seafloor. The present study reveals the response of seismic wave characteristics and amplitude versus offset (AVO) effects of large offset compressional (P) and converted (PS) waves for a GHSZ/free-gas configuration, using a two-dimensional elastic anisotropic modelling technique. The modelling results would provide ‘a priori’ information, which allows unique determination of parameters of seismic models for the design of ocean bottom seismometer experiments over continental margins for the purpose of gas hydrate exploration. The AVO analyses on long offset P and PS waves based on synthetic data yield a typical gas hydrate/free-gas response, as the reflectivity increases with incidence angle.
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Acknowledgements
We would like to thank Dr. V.P. Dimri, Director, NGRI, for permission to publish the results of this study. We are very grateful to an anonymous reviewer for constructive comments, which helped us to improve the manuscript. We would also like to acknowledge the unflagging support of and discussions with S.I. Reddi.
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Rajput, S., Rao, P.P. & Thakur, N.K. Two-dimensional elastic anisotropic/AVO modelling for the identification of BSRs in marine sediments using multicomponent receivers. Geo-Mar Lett 25, 241–247 (2005). https://doi.org/10.1007/s00367-005-0212-7
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DOI: https://doi.org/10.1007/s00367-005-0212-7