摘要
电性源瞬变电磁具有快捷、探测深度大、对异常体探测效果好的特点,然而对其观测分量、装置、电流波形的选择还没有进行过详细的阐述,为此本文做了详细的研究.通过对电性源赤道装置与轴向装置的对比研究,表明赤道装置可以对地下结构取得较好的探测效果,在探测相同深度时,轴向装置收发距较小,信噪比较高.通过对电流波形的研究表明,阶跃激励源激发的场视电阻率从早期到晚期很好的反映了地质结构从浅到深的变化,可以很好的勾勒地电结构的变化,而脉冲波激发的场对目标体反映明显,然而其视电阻率在过渡场阶段存在畸变现象.通过对Hz场和Ex场的研究表明,Hz场在小收发距时即可进行大深度探测,在小收发距下信号强度较高,其应具有较高的信噪比,Ex场需要在大收发距观测,对高阻体探测效果比Hz好.
The ground source transient electromagnetic has the characteristics of quick and deep detection,good detection effect for abnormal body. This paper will study on the selection of its parameters,that have not been detailed by now. By comparative study of the equator device and the dipole device,the dipole device has deeper detection and higher signal noise ratio（ SNR） when the dipole device has the same distance between transmitter and receiving location as the equator device,while the equator device has better detection effect than the dipole device. Based on the research of the source,it shows that the apparent resistivity of the step source from early to late reflects well the geological structure changes from shallow to deep and can outline geoelectric structure changes, the field of impulse source has better detection for abnormal body than the field of the step source. However,the apparent resistivity of the impulse field in the transitional period is distorted. By research on Hz and Ex,it can see that Hz can detect the large depth,with high signal-to-noise ratio,when the distance between transmitter and receiving location is very small,the Ex field has the best detection for high resistance body.
出处
《地球物理学进展》
CSCD
北大核心
2016年第2期913-919,共7页
Progress in Geophysics
基金
国家重大科研装备研制项目"深部资源探测核心装备研发"(ZDYZ2012-1)-05子项目"多通道大功率电法勘探仪"
国防科工委科研项目(科工技[2013]969号)联合资助
关键词
电性源
瞬变电磁
参数选择
the ground source
transient electromagnetic method
parameter selection
