FAVO inversion technique and its application to deep-water sandstone reservoir
Yun LING1,2(), Xiang-Dong DU1, Si-Yuan CAO2
1.CNOOC Research Institute Ltd.,Beijing 100028,China 2.College of Geophysics and Information Engineering,China University of Petroleum,Beijing 102249,China
The frequency dependent reflection coefficient can be obtained by time frequency analysis,based on the AVO theory.Using FAVO (Frequency dependent AVO) inversion technique,the authors obtained the property of velocity dispersion degree.Because of the correlation between the velocity dispersion and pore fluid,the property can be used in fluid detection in the reservoir as an identification factor.In this paper,the authors derived the inversion formula and chose the deep-water sandstone reservoir as the research target.The research on gas sand-body characterization and gas content identification was based on 1D numerical model and 2D real section.The inversion results are well coincident with the drilling results,which shows the effectiveness of the technique in fluid identification of deep-water sandstone reservoirs.
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