摘要
本文研究并建立了水平层状介质中阵列感应测井资料的快速迭代反演算法 ,以便快速有效地重构地层原状电阻率、侵入带电阻率、侵入半径以及层界面深度。首先 ,利用摄动原理和半解析正演模拟技术 ,建立 Fréchet导数矩阵的快速算法 ,该矩阵包含了测井响应对所有模型参数的偏导数 ,且通过规范化处理技术确定测井资料相对摄动与模型向量相对变化之间的一般关系 ,从而克服了模型参数物理量纲的不同对反演算法的影响。在此基础上建立了一种新的快速迭代反演算法 ,即充分利用子线圈系分辨率和探测深度的差异 ,将反演过程分解成两个部分 :1对短源距线圈系和长源距线圈系视电导率分别进行一维迭代反演 ,确定出与实际模型真值更加接近的模型向量 ;2再对整个阵列感应测井资料进行二维迭代反演 ,实现理论模拟与整个测井资料的最佳拟合。
The paper studies and creates a fast iterative inversion algorithm for multi array induction log data in horizontal layered medium,which fast and effectively reconstructs the original resistivity of formation,resistivity in flushed zone,invasion radius and depth of interface.First,using perturbation principle and forward modeling technique of semi analytic solution,we build up fast algorithm of Fréchet derivative matrix,which includes partial derivatives of log response with respect to all model parameters and determine general relation between relative perturbation in log data and relative change of model vectors through normalization processing,overcoming the effects of physical dimensional difference of model parameters on inversion algorithm.Then,the fast iterative inversion algorithm has been created on that basis,that is full use of the difference between vertical resolution of the coil system and surveying depth,we divided the inversion procedure into two parts:first,1 D iterative inversion has been done for apparent conductivity of short coil spacing and long coil spacing respectively in order to get the model vector more closing to the time model;then,2 D iterative inversion has been done for whole multi array induction log data,fulfilling optimum fitting between theoretical modeling data and total log data.The effectness and anti interference ability of the algorithm have been proved by numerical inversion results. Finally,the paper showed the effectiveness and the anti interference ability of the method through numeric inversion results.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2002年第6期644-652,共9页
Oil Geophysical Prospecting
关键词
阵列感应
测井资料
快速迭代反演
Frechet导数矩阵
规范化处理
线圈系
multi array induction, log data,fast iterative inversion, normalization processing of Fréchet derivative matrix, coil system, model, theoretical modeling
