Computing electromagnetic wave resistivity MWD tool''s response using accelerated iteration algorithm for integral equations
利用积分方程的加速迭代算法计算随钻电磁波电阻率测量仪器的响应

The 2D integral equations are computed by an integrated iteration algorithm of modified successive approximation method (MSAM) and Aitken acceleration technique. The longitudinally stratified virgin formation is taken as the background and the computational region is restricted within the borehole and invasion zone in the algorithm, thus the algorithm is qualified for the virtues of small number of unknowns, fast converging speed and high accuracy. The response of the electromagnetic wave resistivity MWD tool in cylindrically symmetrical 2D formation is simulated by the algorithm. The results have shown that the amplitude attenuation and phase shift are affected differently by the borehole, invasion and surrounding shale, and that their radial depth of investigation and vertical resolution are also different. The bed boundary can be accurately located by the crossover point of the compensated amplitude attenuation and phase shift resistivities.