根据已有地质和地球物理研究结果,北京东部平原地区存在多条第四纪隐伏活动断裂。为了查明该区基岩面的起伏情况、断裂的空间展布以及深部断面的延伸情况,2010年初,在北京顺义区庙卷村和朝阳区孙河地区附近完成了2条可控源音频大地电磁测深剖面。文中介绍了可控源音频大地电磁法(CSAMT)隐伏活动断裂勘探的特点、资料采集过程及数据处理方法,结合区域地质资料对研究区域进行了综合地质解释。结果表明:CSAMT法在隐伏活动断裂探测中能给出工区内断裂的构造位置、倾向、断距以及发育规模,为地质分析工作提供可靠的基础资料。CSAMT法已经成为隐伏活动断裂探测中一种重要的地球物理手段,在城市活动断裂探测中发挥着重要的作用。
There are multiple Quaternary buried active faults in the eastern Beijing plain region based on the results obtained from geological and geophysical studies. In order to investigate the condition of bed- rock surface undulation, geometry of the buried faults and the extension of fault planes in the eastern Beijing plain area, two CSAMT profiles were completed in Miaojuan, Shunyi district and Sunhe, Chaoy- an district in early 2010. The paper presents the advantages of CSAMT in exploration of buried active faults, the data collection procedure and the methods used for data processing. Combining with regional geological data, we make integrate interpretation to the geological structures of the study region. The results show that the CSAMT method can be used effectively in the exploration of buried faults. It can reveal the location, dip, displacement, and size of faults in the survey area, which provide reliable and elemental information for geological analysis. This method has become an important geophysical tool in buried fault detection and plays an increasingly important role in exploration of active faults in urban areas.