三维圆柱坐标系下FDTD法对电磁波传播测井的数值模拟

摘要

Eletromagnetic Propagation Logging Tool (EPT) is a high-frequency electromagnetic logging tool. It can measure the permittivity of formation, in some cases, it is better than resis-tivity logging in regard to the distinction between oil and water layer. The FDTD is used to make forward modeling of electromagnetic propagation logging in simple 3-D cylindrical formation, the Mur first order and second order absorbing boundary conditions are used in the different bounda-ries of cylinder models, then a special method is used to calculate the eletromagnetic fields in the central axis of cylinder models. On this basis, simulated are the responses of electromagnetic propagation logging in oil-water layer, the result is good.%电磁波传播测井EPT(Eletromaganetic Propagation Logging Tool)是一种高频电磁波测井方法,它可以测量地层的介电常数,在区分油水层方而有时较电阻率测井效果明显.运用时域有限差分法FDTD(Finite DifferenceTime Domain Method)法在三维圆柱坐标系下对电磁波传播测井进行了数值模拟,在圆柱体模型的不同边界处综合运用了Mur一阶和Mur二阶吸收边界条件并且在中心轴上对电磁场的计算运用了特殊的处理方法.在此基础上模拟分析了电磁波传播测井在油水层中的测井响应特征,得到了良好的效果.