矿井瞬变电磁法超前探测合成孔径成像研究  

Synthetic aperture imaging in advanced detection of roadway using the mine transient electromagnetic method

作　　者：程久龙[1,2] 陈丁[2] 薛国强[3] 邱浩[4] 周项通 

机构地区：[1]中国矿业大学(北京)煤炭资源与安全开采国家重点实验室,北京100083 [2]中国矿业大学(北京)地球科学与测绘工程学院,北京100083 [3]中国科学院矿产资源研究重点实验室,中国科学院地质与地球物理研究所,北京100029 [4]煤炭科学研究总院矿山安全技术研究分院,北京100013

出　　处：《地球物理学报》2016年第2期731-738,共8页Chinese Journal of Geophysics

基　　金：国家自然科学基金项目(51574250;51174210);高等学校博士学科点专项科研基金项目(20120023110014)联合资助

摘　　要：在矿井瞬变电磁超前探测数据处理和解释中,为了更好地识别巷道前方含水体电性分界面,利用扩散场与波动场间的函数关系,将矿井瞬变电磁法超前探测中瞬变电磁波场转换为拟地震波场,实现波场转换.同时,为了解决波场转换后信号幅值偏弱,以增加信噪比利于解释,利用雷达的合成孔径方法对波场转换后的拟地震信号进行相关叠加处理.将矿井瞬变电磁法巷道超前探测的同一测点不同探测方向的数据作为孔径数据进行合成孔径成像,以突出弱异常而提高信噪比,结合应用实例验证了方法的效果.研究表明,矿井瞬变电磁法合成孔径成像方法能够提高电性界面信息的信噪比和界面几何分辨率,对矿井瞬变电磁法精细超前探测含水构造具有重要的理论意义和应用价值.During the data processing and interpretation of the mine transient electromagnetic method（MTEM）,it is an important goal to improve the identification of the geo-electrical interface between low resistivity abnormal body and surrounding rock in advanced detection.To achieve this end,the transient electromagnetic field is transformed into the pseudo-seismic wavefield based on the function relationship between spreading electromagnetic field and seismic wavefield in whole-space.Meanwhile,the signal of pseudo-seismic after transform is processed with correlative stack to strengthen the amplitude and improve signal-noise-ratio（SNR）using the synthetic aperture imaging（SAI）.The data of different detection directions on one surveying point in the MTEM are imaged as aperture data,which would highlight weak anomalies and improve SNR.In addition,the application effect of SAI was testified with the in-site advanced detection in roadway using the MTEM.The results show that the SAI of the MTEM can improveSNR of the electrical interface information and highlight the geometrical resolution to increase exploration accuracy.The technique is significant theoretically and practically in accurate advanced detection of aquifer structure by the MTEM.

关 键 词：矿井瞬变电磁法 波场转换 拟地震信号 合成孔径成像 电性界面 

分 类 号：P631[天文地球—地质矿产勘探]