岩脉的大地电磁响应的研究

A STUDY ON MT RESPONSES OF A DIKE

TM极化时,当测点越过界面时视电阻率均发生变化,基底较深时能放大界面附近的异常,当基底较深、频率较高时,高阻一侧相位低于45°,低阻一侧相位高于45°。TE极化时,只有基底为高阻时越过界面时视电阻率才发生变化,当基底为高阻且频率较高时,相位在界面两侧发生变化。通过岩脉时若相位无变化,岩脉是窄的。

For TM polarization, the apparent resistivities always change when measure station passes over a dike. The response may be magnified in the neighboring area of the dike in the circumstances of deep buried basement. The phase of highresistive side is less than 45 degrees and the phase of lowresistive side exceeds 45 degrees in the case of basement is deep and the frequency is high. For TE polarization, only if the resistance of basement is high, the apparent resistivity then varies when measure station passes over the dike. When the resistance of the basement is high and the frequency is high the phase changes. However when the dike is not wide enough the phase will not change.