感应测井趋肤效应校正方法研究

传统的感应测井趋肤效应校正方法包括乘加因子法和函数非线性拟合法，乘加因子法需要对视电导率曲线进行分段，函数非线性拟合法则要选取合适的拟合函数，这两种方法均含有人为因素，误差较大，不具备通用性。现代感应测井仪器既测量视电导率的实部分量也测量其虚部分量，基于此提出了迭代校正方法，即利用视电导率实部分量与虚部分量之和，通过对趋肤深度的迭代来实现感应测井仪测量信号的趋肤效应校正。该方法的迭代公式简单，物理意义明确，在通常的地层条件下该方法的收敛条件均能得到满足。设计了1个复合线圈系，在均匀地层情况下，对传统校正方法和迭代校正方法的校正效果进行了对比分析。结果表明，迭代校正法的效果明显优于传统校正方法，且适用于各种线圈系结构，具有很强的通用性。

Study on correction method of skin effect for induction logging

Traditional correction methods of skin effect for induction logging include multiplying adding factor method and function non-linear fitting method.The multiplying adding factor method must divide apparent conductivity into many segments and the function fitting method must select appropriate fitting function.Both of them involve artificial factors and obvious correction errors,without commonality.Modern induction logging instruments measure both the real and the imaginary component of apparent conductivity.On this basis,we proposed an iteration correction method,which iterates the skin depth to achieve the correction of skin effect for induction logging measured signals by using the real and the imaginary component of the apparent conductivity.The method has simple iterative formula and specific physical significance.Moreover,it converges within the common range of the earth conductivity.In the case of homogeneous formation,a complex coil system was designed,and the correction effects of traditional correction method and iterative correction method were compared and analyzed.Numerical results indicate that the iteration correction method is much better than the traditional method and applicable to various coil system.