一种基于MFWVD高精度时频谱分析的储层预测新方法  

New reservoir prediction method based on MFWVD high precision time-frequency spectrum analysis

作　　者：夏连军[1] 刘震[2] 朱相羽 罗震 张军华[2] 王喜安 胡逸甫 XIA LianJun;LIU Zhen;ZHU XiangYu;LUO Zhen;ZHANG JunHua;WANG Xian;HU YiFu(Geophysical Research Institute of Jiangsu Oilfield Company,SINOPEC,Nanjing 210046,China;National Key Laboratory of Deep Oil and Gas,China University of Petroleum,Qingdao 266580,China;Jiangsu Oil Field Branch,SINOPEC,Yangzhou 225000,China)

机构地区：[1]中国石化江苏油田分公司物探研究院,南京210046 [2]深层油气全国重点实验室,中国石油大学(华东),青岛266580 [3]中国石化江苏油田分公司,扬州225000

出　　处：《地球物理学进展》2023年第4期1647-1655,共9页Progress in Geophysics

基　　金：国家自然科学基金项目(42072169);中国石化先导项目(P22162)联合资助。

摘　　要：薄互储层普遍存在砂体叠置、地层含灰、厚度较薄、横向非均质性较强的特点,时间域的目标处理与单一的谱分析方法,难以满足储层精细描述的需求,需要开展高精度的时频分析.本文针对GST线性方法分辨率较低、双线性WVD方法受交叉项干扰严重的问题,设计了一种先用SPWVD与WVD幅度谱比控制交叉项干扰、再用高斯函数光滑输出的遮罩滤波器.用该滤波器遮罩WVD谱,可得到高精度、高保真的MFWVD谱.使用双线性Chirp理论信号对本文方法进行验证,MFWVD谱的分辨率、信噪比明显优于GST、WVD和SPWVD谱.将方法应用于实际地震资料,进一步计算高精度MFWVD谱分布的斜率,发现含油砂体具有斜率值小或负斜率的特征规律,预测结果与砂体分布有很好的相关性,解决了研究区复杂含灰储层预测的技术难题,为时频谱分析预测有利储层提供了一种新的方法技术.Thin-inter bed reservoirs are generally characterized by superposition of sand bodies,formation bearing ash,thin thickness and strong lateral heterogeneity.Therefore,it is difficult for target processing in time domain and single time-frequency analysis method to meet the requirements of fine reservoir description,so it is necessary to carry out high-precision time-frequency analysis.Aiming at the problems of low resolution of linear methods such as GST and serious cross interference term of bilinear WVD methods,a mask filter is designed which first uses the amplitude spectrum ratio of SPWVD and WVD to control cross term interference and then uses Gaussian function to smooth output.High precision and high fidelity MFWVD spectrum can be obtained by masking WVD spectrum with this filter.The proposed method is verified by bilinear Chirp signals.The resolution and signal-to-noise ratio of MFWVD spectrum are obviously better than that of GST,WVD and SPWVD spectrum.The method is applied to the practical seismic data,and the slope of the high-precision spectral distribution obtained by MFWVD is further calculated.It is found that the oil-bearing sand body has the characteristic pattern of small slope value or negative slope value,and the prediction results have a good correlation with the sand body distribution,which solves the technicalproblem of predicting complex marl-bearing reservoirs in the study area and provides a new method technique for predicting favorable reservoirs by time-frequency spectrum analysis.

关 键 词：时频分析 SPWVD MFWVD 遮罩滤波器 储层预测 

分 类 号：P631[天文地球—地质矿产勘探]