Abstract

Use of traditional interpretations of seismic data to map reservoir geometry and extent are often quite challenging due to presence of noise, besides intrinsic limitations caused by tuning arising out of band limited nature of the surface seismic data. Inversion of seismic data provides elastic properties which have lesser noise with tuning effect reduced significantly. Thus, inverted elastic properties give a clearer picture of the subsurface. It also provides a platform for quantitative interpretation from a rock physics standpoint. In this study we inverted simultaneously six angle stacks from a block in Cambay basin to derive acoustic impedance (AI) and the ratio of compressional and shear wave velocities (Vp/Vs). Cambay shales are characterized by high AI and low Vp/Vs. Simultaneous Inversion was able to discriminate lithology, i.e. reservoir sands and their spatial distribution through geo-body capture. Sand thickness map generated from geobodies extracted from the inverted elastic properties provided valuable information about the reservoir architecture.