川西深层须家河组气藏储层预测关键技术

Key prediction method for deep Upper Triassic Xujiahe Formation gas reservoirs in West Sichuan,China

探讨川西深层上三叠统须家河组气藏优质储层预测、裂缝发育带预测及含气性检测方法。针对川西新场气田须家河组气藏,在储层地震响应特征和有利沉积相带预测的基础上,利用AVO叠前同时反演预测相对优质储层的分布;采用纵横波资料联合的裂缝检测方法,进行地震属性裂缝预测、P波方位各向异性裂缝预测、横波分裂裂缝检测及离散裂缝网络建模的裂缝表征等多方法、多尺度的裂缝综合预测;利用纵波和横波联合反演进行储层的含气性预测,并形成了须家河组气藏储层预测关键技术。结果表明该技术系列可以较好地预测须家河组气藏相对高孔隙储层、裂缝发育带及含气有利区,钻井成功率从15%提高到89%。

This paper approaches the prediction ways of the high quality reservoirs and the development of fractures and the detection of gas-bearing quality in the deep Upper Triassic Xujiahe Formation gas reservoir in West Sichuan.Aiming at the Xujiahe Formation gas reservoir in West Sichuan,based on the features of seismic response and the favorable sedimentary facies distribution,the distribution of high-quality reservoir is predicted by using AVO simultaneous inversion.The joint method of P-wave and convert wave is used to predict the fractures of seismic attribute,P-wave azimuthal anisotropy,shear wave splitting and the multi-scale fractures,and model the discrete fracture net.The prediction of gas-bearing quality is finished by jointing inversion of P-wave and convert wave and then,the key technologies of reservoir prediction for the Xujiahe Formation gas reservoir are developed.Finally,the results show that those technologies can better predict the reservoirs of relative high porosity,developing fractures and the beneficial gas-bearing areas of Xujiahe Formation.The rate of drilling success is 15%-89%.