摘要
Aiming at two problems appeared in transient electromagnetic method of fixed loop data inverted by in-loop way and the low-resistivity shielding effect in down hole TEM prospecting,we make some forward and inversion models for the first case and make four forward models for the second case by using Maxwell software.The results indicate that there is a risk for the first problem especially under low resistivity of the layer and distance between central point and station.The later forward results tell us that when there is a low resistivity layer underground we can increase the transmitted magnetic moment and measure magnetic can collect the target singles beneath the low resistivity layer,and the results also illustrate that X component is more sensitivity to conductor than Z component in downhole TEM prospecting.