Inversion of Shear Wave Anisotropic Parameters in Strongly Anisotropic Formations

摘要: Deepwater reservoirs use highly deviated wells to reduce cost and enhance hydrocarbon recovery. Due the strong anisotropic nature of many marine sediments, seismic imaging interpretation can improve reservoir characterization. Sonic logs acquired in these are strongly dependent on well deviations. Crossdipole sonic logging provides apparent shear wave anisotropy wells, which be far from truth. Although parameters have been successfully obtained using data several deviations or single based weak approximation, estimation remains a challenge. Using sensitivity analysis, we find Stoneley velocity has good qSV SH velocities wells. We create linear inversion scheme estimate SH, SV, logged one well. first apply method laboratory measurements boreholes various relative symmetry axis an material. then field set also compute vertical horizontal this inverted elastic constants. INTRODUCTION In recent years, significant discoveries made deepwater fields. Offshore development uses high-angle drilling Since offshore formations often exhibit anisotropy, it becomes very important take into account processing (Tsvankin, 1995, Ren et al., 2005). For example, converted P-S waves image through gas cloud that would obstruct P because sensitive theformation frame but not fluid content. Therefore, when obtain both S images, they show different amplitude polarization. Joint may yield formation