四川盆地涪陵地区茅口组热液白云岩储层预测

Hydrothermal dolomite reservoir prediction for Maokou formation in Fuling area,Sichuan basin

在分析四川盆地涪陵地区中二叠统茅口组热液白云岩储层发育主控因素的基础上,确定了"基底断裂精细描述+有利沉积相带分析+精细地震反演的热液白云岩储层综合预测"技术路线。针对该区灰岩与白云岩的波阻抗值重叠、仅用叠后波阻抗反演方法难以识别储层的难题,在钻井资料统计分析基础上,综合应用叠后地震反演获得的波阻抗值和叠前地震反演获得的纵横波速比V_p/V_s,实现了对热液白云岩储层的有效预测。

With reference to the successful international experiences in hydrothermal dolomite reservoir exploration and production,this paper has studied the main factors controlling the development of hydrothermal dolomite reservoirs in middle permian Maokou formation in Fuling area.On the basis thereof,the approach to predicting the distribution of hydrothermal dolomite reservoirs of Maokou formation in this region has been proposed,which organically combines fine description of basement fault and analysis of favorable sedimentary fades and fine seismic inversion.In the overlapped area between the high-energy fades zone in the middle ramp and basement fault zone,dolomite and limestone can be effectively distinguished from each other and prediction of dolomite reservoir can be performed by combing seismic post-stack acoustic impedance inversion and prestack elastic inversion and using the parameters of acoustic impedance,AI,and Vp/Vs in an integrated manner.