为了提高瞬变电磁法对地探测精度,提出了一种新颖的瞬变电磁装置-多孔径发射装置,并进行了多孔径瞬变电磁场物理模拟观测.分别使用四孔径发射装置和常规回线发射装置,进行不同收-发距情况下的一次场观测,并对铜板在不同埋藏深度情况下的二次响应进行观测,通过比较两种不同装置下的响应曲线和计算观测数据误差,最终发现使用四孔径发射装置可使一次场强度提高34%,可使二次场强度提高31%.结论表明,多孔径发射源可以改变电磁场的空间分布,认为瞬变电磁场存在类相干现象.研究成果对提高瞬变电磁的探测精度具有很重要的意义.
In order to improve the resolution of TEM to detect buried targets, a new multi-aperture transient electromagnetic survey configuration is introduced and used to survey TEM response in this paper. Both of multi aperture system and normal TEM configuration in the condition of different receiver-transmitter distances are used to observe the primary field and secondary field corresponding to copper plate. The response curves and the surveyed data error of two kinds of configuration are compared. It has been found that the multi-aperture transmitter system can improve the primary filed intensity higher more than 34 %, and bring the secondary field response high more than 31%. The survey result shows that the multi aperture TEM transmitter configuration can really change the distribution of magnetic field. It is suggested that there really exists the phenomenon of TEM field coherent like . It is of significance to improve the precision of TEM data.