四川龙门山地区超长周期大地电磁探测

The Long-period Magnetotelluricin Detection in Sichuan Longmenshan Area

大地电磁超长周期信号是指1000-100000s之间的天然场源电磁波,为了提高对地下介质的探测深度和研究更深层的构造和结构,需要采集周期大于1000s的电磁场信号。2012年9-12月,笔者使用德国产ADU-07系统的感应式磁传感器和乌克兰产LEMI-417系统的磁通门在四川龙门山地区进行超长周期大地电磁数据采集实验,本文通过将感应式磁传感器和磁通门测试数据进行对比研究,探讨感应式磁传感器和磁通门的有效频谱范围,以及使用LEMI-417系统磁通门进行超长周期数据采集的可行性等,为推广和使用超长周期数据采集工作提供一个参考样本。

The long-period magnetotelluric signal refers to natural source electromagnetic wave between 1000sand-100000s,In order to further improve the detection depth of underground medium and study the deeper structure,sample collection cycle of electromagnetic signal is needed to be more than 1000s.From September to December in 2012,systematic inductive magnetic sensors of Germany ADU-07and flux gate of Ukraine LEMI-417are used in the long-period test of Sichuan Longmenshan area to collect magnetotelluric data.From comparative analysis of the data from the inductive magnetic sensors and fluxgatethe,the effective range of frequency signal and the feasibility of LEMI-417systematic fluxgate for the collection of long-period data are investigated.which provides a reference sample for the development and use of long-period data collectionn.