湖相致密复杂岩性地震识别技术  

A seismic recognition technology of lacustrine complex tight lithology

作　　者：赵万金[1] 唐传章 王孟华 王余泉 杨德相 赵伟森 周从安 常建华 卢昊 

机构地区：[1]中国石油勘探开发研究院西北分院,甘肃兰州730020 [2]中国石油华北油田公司,河北任丘062552

出　　处：《石油学报》2015年第B11期59-67,共9页Acta Petrolei Sinica

基　　金：中国石油天然气股份有限公司重大科技专项(2014E-035);中国石油天然气股份有限公司物探攻关项目(2013-03-06)资助

摘　　要：针对湖相复杂致密岩性地震预测难点多的特点,提出一种在高分辨率层序约束下利用贝叶斯统计方法识别致密岩性的思路。应用地震时频旋回技术和Wheeler变换与反变换技术建立三维高分辨率层序格架,划分沉积体系域。运用中观尺度测井数据开展岩石物理交会分析,利用实验室X-射线衍射数据(XRD)和等效介质模型进一步从微观尺度分析,最终确定拟声波阻抗和纵、横波速度比是区分岩性的敏感参数。在此基础上,开展高分辨率层序约束下的波阻抗及纵、横波速度比反演,而后利用反演属性进行贝叶斯统计,在井上岩性识别精度高的前提下,利用得到的条件概率分布预测空间岩性最佳分布,最后对岩性分类结果进行对比分析。实际应用证明,在高分辨率层序约束反演的基础上利用贝叶斯统计识别复杂致密岩性具有较高的吻合率,该项技术适用于湖相复杂致密岩性识别。Aiming at much more difficulties in predicting seismic prediction of complex lacustrine tight lithology, under constraint of high- resolution sequence, a method of recognizing tight lithology using Bayes statistics way was proposed. High-resolution 313 sequence framework was established using seismic time-frequency cycle technology together with forward/inverse Wheeler transform technology, and sedimentary system tracts were divided. Petrophysics cross-plot analysis was conducted with mesoscale logging data. Laboratorial X ray diffraction data and equivalent medium model were used for further micro-scale analysis, so as to determine pseudo acoustic imped- ance and ratio of P- and S- waves velocity （Vp/Vs）as sensitive parameters for lithology recognition. On this basis, acoustic impedance and Vp/Vs inversion was carried out under constraint of high-resolution sequence. Then Bayes statistics was conducted using inversed at- tributes. Under high-precision lithology recognition, the obtained conditional probability distribution was adopted to predict optimal dis- tribution of spatial lithology, and classification results of lithology were conducted comparative analysis. The practical application shows that on the basis of constrained inversion with high-resolution sequence, the complex tight lithology recognized by Bayes statistics had a high consistency, and this technology is suitable for recognition of complex lacustrine tight lithology.

关 键 词：致密岩性 高分辨率层序 体系域 岩石物理 反演 贝叶斯统计 

分 类 号：TE132.2[石油与天然气工程—油气勘探]