APPLICATION OF PRE-STACK SEISMIC INVERSION TO PREDICTION OF HIGH-QUALITY GLUTENITE RESERVOIRS IN QINGSHUI DISTRICT

In the Qingshui district of the Liaohe Depression, the 1st Member of the Shahejie Formation was widely deposited as a fan-delta glutenite. The glutenite, together with syn-deposited dark shale, forms good source-reservoir -cap systems for lithologic reservoirs. The main reservoirs of the 1st Member of the Shahejie Formation are made up by pebbly fine sandstone. However, due to the existence of carbonate cement, wave impedance of non-reservoirs, such as limy shale and limy siltstone, is hard to be distinguished from that of the reservoirs. That is to say, high-quality reservoirs can not be predicted precisely by conventional stacked impedance inversion. Petrophysical analysis suggests that λρ and μρ are good elastic parameters for recognition of high-quality reservoirs. Based on the optimizing process of pre-stack gathers and transverse wave prediction, λρ and μρ have been obtained by pre-stack seismic inversion and used to predict the distribution pattern of high-quality fan-delta glutenite reservoirs to promote exploration in the glutenite lithologic reservoir in the Qingshui district.