Abstract：
Multi-component exploration has many advantages over ordinary P-wave exploration. PP/PS joint AVO analysis and inversion are useful and powerful methods to discriminate between reservoir and non-productive lithology. In this paper, we derive a new PS-wave reflection coefficient approximation equation which is more accurate at larger incidence angles. The equation is simplifi ed for small incidence angles, which makes AVO analysis clearer and easier for angles less than 30 degrees. Based on this approximation, a PP/PS joint inversion is introduced. A real data example shows that oil sands, brine sands and shales can be differentiated based on the P- to S-wave velocity ratio from the PP/PS joint inversion. Fluid factors and Poisson’s ratio also indicate an anomaly in the target zone at the oil well location.
WANG Pu,HU Tian-Yue. AVO approximation for PS-wave and its application in PP/PS joint inversion[J]. APPLIED GEOPHYSICS, 2011, 8(3): 189-196.
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2011, Vol. 8 
