The deterministic inversion technology and the post-stack geo-statistics inversion technology have been widely adopted in prediction of tight clastic reservoirs. However

they are not very effective in prediction of thin reservoirs with complex lithologic structure and wave impedance. The combination of the simultaneous inversion technology and the prestack geo-statistics inversion technology is effectively applied in the quantitative prediction of such reservoirs. The application of these technologies can not only improve the vertical and horizontal resolution but also can recognize effective reservoirs even when the impedances of surrounding rocks and reservoirs are overlapped. Although the pre-stack simultaneous inversion technology can extract P-wave impedance

S-wave impedance

v P / v S and density

and can recognize reservoirs with complex impedance

it has limited vertical resolution due to the limitation of frequency band. Stochastic modeling-based pre-stack geo-statistics inversion technology can effectively integrate geological

logging and 3D seismic data

greatly improve both vertical and lateral resolutions

thus can realize fine description of reservoirs. Based on deterministic pre-stack inversion

this technology can effectively identify thin reservoirs and thin interbedded reservoirs. It has been successfully applied to the prediction of reservoirs in the 4thMember of Xujiahe Fm in Xinchang gas field of western Sichuan Basin

a continental tight clastic gas field.