子波地震道分解与重构技术在复杂储层预测中的应用

30构造区位于辽西低凸起和石臼坨凸起转换区,东侧为渤中凹陷,西侧为秦南凹陷,具有双向供油的优越条件。该区在馆陶组、沙河街组、中生界等多个层系获得油气流,其中中生界获得高产油气流,为一复式含油气构造区。该区地层结构比较复杂,东营组、沙河街组、孔店组均遭到不同程度的剥蚀,钻探的4口井钻遇的地层变化较大。储层横向变化较大,特别是沙河街组储层以滩相的颗粒灰岩为主,横向变化快,地震反射不明显,预测难度较大。针对该构造区古近系勘探中存在的储层问题,应用国内较新的子波地震道分解与重构技术,对构造区内的地震资料进行多子波分解处理、重构等,结合钻井资料,优选出对储层比较敏感的的子波频谱范围,形成一个新的地震数据体。应用新数据体的常规地震属性对储层进行预测;利用新数据体频谱的衰减对油层段含烃情况进行预测,最终明确了30-2、30-2S两个构造区储层的发育状况及储层流体为烃类的可能性较大,达到了较好的预测效果。

Application of seismic trace-wavelet decomposition and reconfiguration technology in complex reservoir prediction

Structure Area 30 is located at the transform zone of Liaoxi Uplift and Shijiutuo Uplift.In this structure area,Bozhong Sag is in the east and Qinnan Sag is in the west,having the favorable condition of double-way oil supply.Hydrocarbon flows are obtained in series of strata in this area,such as Guantao Formation,Shahejie Formation and Mesozoic strata,in which the high production oil and gas are in Mesozoic strata.However,the strata structure is so complicated that Dongying Formation,Shahejie Formation and Kongdian Formation are all eroded differently.Drilling results of four wells indicate that the reservoirs have large lateral change,especially the Shahejie Formation is mainly the lithology of granular limestone in bank facies,whose reservoir prediction is difficult because of the lateral change.Aimed at the problem of Paleogene exploration in this structure area,the seismic trace-wavelet decomposition and reconfiguration method is applied to process seismic data based on the well drilling data,which optimizes the distribution range of wavelet spectra and obtains new seismic data cube for reservoir prediction.The spectra attenuation of new seismic data cube is also used to predict hydrocarbon in reservoir.Finally,it makes clear that the reservoirs develop in Structure Area 30-2 and 30-2S with more hydrocarbon flows.A good prediction effect has been obtained.