广域电磁与伪随机信号电磁法在四川盆地页岩气勘探中的应用  

The Application of Wide-Area Electromagnetic and Pseudo-Random Signal Electromagnetic Methods to the Shale Gas Exploration in the Sichuan Basin

作　　者：武斌[1] 谭章坤 曾楷 邹俊 陈宁[1] 余舟 陈挺 WU Bin;TAN Zhang-kun;ZENG Kai;ZOU Jun;CHEN Ning;YU Zhou;CHEN Ting(Geophysical Exploration Team,SBGEEMR,Chengdu 610072;Sichuan Zhongcheng Institute of Coalfield Geophysical Engineering,Chengdu 610072;The 113rd Geological Team,BGEEMRSP,Luzhou,Sichuan 610100)

机构地区：[1]四川省地质矿产勘查开发局物探队,成都610072 [2]四川中成煤田物探工程院有限公司,成都610000 [3]四川省地质矿产勘查开发局一一三地质队,泸州646000

出　　处：《四川地质学报》2021年第3期474-477,共4页Acta Geologica Sichuan

摘　　要：广域电磁与伪随机信号电磁法采用伪随机信号发射,突破远区限制,可观测面积大,信号强、精度高、只观测场的一个分量,野外效率高。伪随机信号电磁法一次能同时发送和接收多个强度大体相当的主频率信号,成倍地提高电磁法的野外效率。本文将广域电磁与伪随机信号电磁法应用于四川盆地某页岩气区块,结果表明它在干扰较强的地区仍然能够获得深部5~6km的有效数据,具有抗干扰能力强、勘探深度大的优点;同时广域电磁法在大套地层划分、油气层识别、断层及构造识别方面的效果显著。Wide-area electromagnetic and pseudo-random signal electromagnetic methods are characterized by large observation area,strong signal,high precision and high efficiency thanks to using a pseudo-random signal.The pseudo-random signal electromagnetic method can simultaneously transmit and receive multiple main frequency signals of roughly equal intensity,thus doubles the field efficiency of the electromagnetic method.The application of the wide-area electromagnetic and pseudo-random signal electromagnetic methods to the geophysical exploration of a shale gas block in the Sichuan basin indicates that it can still obtain the effective data of 5-6 km depth in the area with strong interference.The wide-area electromagnetic method is effective in stratigraphic division,oil and gas layer identification and structure identification.

关 键 词：广域电磁法 伪随机信号 页岩气勘探 

分 类 号：P319[天文地球—固体地球物理学]