瞬变电磁法回线源形态对一次场畸变特征研究  

Study on the form of transient electromagnetic loop source versus the distortion characteristics of the primary field

作　　者：马炳镇 

机构地区：[1]中煤科工集团西安研究院有限公司,陕西西安710077

出　　处：《煤田地质与勘探》2017年第6期154-158,共5页Coal Geology & Exploration

基　　金：国家自然科学基金项目(41374150)~~

摘　　要：近年来,地面瞬变电磁法在矿产资源、水文地质勘查等领域均取得了良好的勘探效果,而当地表条件较差时,探测结果的可靠性明显降低。究其原因,矩形回线源的布设随地形起伏致使形态变化是重要影响因素之一。根据毕奥—萨法尔定律,对通电矩形回线在空间任意点所产生磁场进行计算。通过对比、分析水平矩形回线源和起伏矩形回线源一次场地下介质不同深度三分量的分布特征,总结得出起伏回线源一次场的畸变与源的形态有明显的相关性,其特征表现为浅部畸变程度严重,随着深度的增加畸变程度明显减弱,以上研究为瞬变电磁法探测中地形影响的认识和校正工作提供了理论指导。In recent years, the ground transient electromagnetic method has achieved good results in the field of mineral resources, hydrogeological exploration and other fields, and the reliability of the detection results decreases obviously when the surface condition is not good. One of the influencing factors is that the layout of rectangle loop with topographic relief makes its shape change. According to Biot-shaffar law, the magnetic field induced by electrified rectangular loop at any point in space is calculated. Through comparison and analysis of the distribution characteristics of three components of primary field of horizontal and undulating loop sources in subsurface media at different depth, it is concluded that the distortion of the primary field of the undulating loop source is obviously related to the shape of the source, its features are shown as serious distortion at shallow part, with increase of depth, the distortion weakens evidently. The above research provides theoretical guidance for understanding and correction of the topographic effects in transient electromagnetic exploration.

关 键 词：瞬变电磁法 起伏回线源 三分量 畸变特征 

分 类 号：P631[天文地球—地质矿产勘探]