中心回线关断时间对海洋电磁响应影响研究

0Influence of the turn-off time with central loop device on its marine electromagnetic response

海洋可控源电磁探测利用海水中电场或磁场与海底电导率之间的关系来获取海底介质信息,研究海底内部组成和构造;给出了由频率域电磁响应计算时间域电磁响应的方法,仿真分析关断时间对海洋可控源中心回线装置时间域电磁探测响应的影响,结果表明,时间域可控源电磁探测发射电流的关断时间不仅影响接收到的早期信号的幅值,而且影响对海底浅部介质的分辨能力。

Marine controlled source electromagnetic （MCSEM） detection uses the relationship between the electric or magnetic field in sea water and the conductivity of seabed to obtain the media information of seabed, so as to study the submarine internal composition and structure. This paper presents a method to calculate the time domain electromagnetic response by frequency domain electromagnetic re- sponse, and analyzes the influence of off-time on the response of time-domain elec- tromagnetic detection of marine controlled source with central loop device by simu- lation. The results show that the off-time of the transmitter current of time-domain controlled source electromagnetic detection not only influences the amplitude of the early received signals, but also affects the resolving power to the media in the shallow seabed.