海底瞬变电磁探测技术的装置参数研究及实验  

Equipment parameters and experiment of sea-floor transient electromagnetic method

作　　者：李慧[1] 林君[1] 王艳[1] 周国华[1] 周逢道[1] 刘长胜[1] 嵇艳鞠[1] 

机构地区：[1]吉林大学地球信息探测仪器教育部重点实验室

出　　处：《电波科学学报》2006年第5期659-665,共7页Chinese Journal of Radio Science

基　　金：国家高新技术发展计划资助项目(2002AA615030);长春市科技计划项目(05GG38);吉林省教育厅科研计划项目(吉教科合字[2005]第118号)

摘　　要：可控源时间域电磁法应用在海底探测,需要确定装置参数,通过实验和理论计算确定了发射频率的最大值;分析了发射线圈的电性对发射电流后沿的影响,确定了作为发射线圈的导线的时间常数应尽量小;对接收线圈的参数及过渡过程进行了理论分析和室内模型实验,理论计算了接收线圈电路模型在发射电流斜阶跃下降和关断后在欠阻尼、临界阻尼和过阻尼状态的一次感应电动势解的情况,确定了采用并联匹配电阻消除振荡的方法,并依据所分析的装置参数设计实施了海上实验,探测出海底低阻体的准确位置。For a sea-floor transient electromagnetic exploration system, its maximum transmitting frequency may be chosen as 200 Hz by supposing the sea-floor as horizontal thin conductive plates. By analyzing the parameters of the transmitting loop and the effect of late-time of transmitting current, a small time constant of wire of transmitting loop is determined. By calculating the response curve of the receiver loop circuit in the cases of different damp coefficients, a parallel matched resistance is employed to remove the vibrating phenomenon. Based on the analysis, the field experiment on the sea is accomplished and the body of low resistivity is detected.

关 键 词：海底瞬变电磁法 发射线圈 接收线圈 感应电动势 过渡过程 

分 类 号：P319[天文地球—固体地球物理学]