密井网条件下地质统计学岩性反演在河道砂体预测中的应用  

Stochastic Lithology Inversion in Condition of Close Well Spacing and Its Application in the Prediction of Channel Sandbody

作　　者：张秀丽[1] Zhang Xiuli(Exploration and Development Institute of Daqing Oilfield Company Ltd.,Daqing,Heilongjiang 163712)

机构地区：[1]大庆油田有限责任公司勘探开发研究院

出　　处：《石油工业计算机应用》2018年第2期35-37,2,共4页Computer Applications Of Petroleum

摘　　要：大庆长垣密井网区,井多、层多、储层厚度薄、横向非均质性强,纵波阻抗对储层和非储层响应特征不明显,建立纵波阻抗与识别砂岩敏感的伽马曲线岩石物理图版,重构新的砂泥岩曲线。在此基础上,应用测井上纵向分辨率高、地震横向密集的优势,采用井震结合地质统计学岩性反演,获得三维高分辨率砂岩概率体。利用高精度反演结果精细刻画薄层砂体的边界、走向及规模等,在此基础上指导砂体连通性分析和注采关系分析等具有较好的应用效果。这对于老油区开发后期储层精细油藏描述和剩余油的挖潜具有重要意义。The main reservoir type of the old oil fields in eastern China is channel sandbody.Further tapping the potential of old oil fields in eastern China is facing one of the most important problems,which is the close well spacing and 3D seismic data are combined for prediction of channel sandbody.In Saertu reservoir of Daqing oilfield as an example,the method of stochastic seismic inversion in condition of close well spacing and its application in the prediction of channel sandbody was studied.Research shows that the key technology of stochastic seismic inversion in condition of close well spacing include to seismic data resampling,correlation analysis of well logging,extraction of change wavelet,sequential Gauss simulation inversion of configuration,and so on.Under the condition of different sandbody thickness,the coincidence rate of stochastic seismic inversion results is different.Less than 1m sandstone low precision(coincidence rate 70%).More than 3m sandbody can basically be identified(coincidence rate 91%).Identification of 2-3m Sand body is poor(coincidence rate 83%).Identification accuracy of less than 1m Sandbody is low(coincidence rate 70%).With decreasing thickness of sandbody,the closer well spacing,the smaller decline of the prediction accuracy.Using the method of seismic inversion guiding and well microfacies controlling,and according to the difference of logging curve and inversion profile,The boundary and direction of single channel,superimposition relationship of interwell sandbody and narrow channel sandbody can be described accurately.In the control channel sandbody sedimentary model,using the results of stochastic seismic inversion,detailed description of the channel sandbody is feasible at the later stage of oilfield development,and it is obvious effect.

关 键 词：地质统计学 岩性反演 井震结合 储层预测 大庆油田 

分 类 号：P628.2[天文地球—地质矿产勘探]