套管井电磁测井技术及套管影响规律研究  

On Electromagnetic Logging Technology in Cased Hole and Its Casing Influence

作　　者：宋汐瑾[1] 党瑞荣[1] 董昭[2] 

机构地区：[1]西安石油大学光电油气测井与检测教育部重点实验室,陕西西安710065 [2]长庆油田第一采油厂,陕西延安716000

出　　处：《测井技术》2010年第2期143-145,共3页Well Logging Technology

基　　金：国家863项目(2007AA06Z217)

摘　　要：对套管井中发射线圈与接收线圈在轴向排列条件下，发射线圈通以交变电流时，接收线圈上的电磁场响应进行了数值模拟。确定了发射电流频率的最大值，并分析了套管厚度及磁导率等参数对接收线圈中感应电动势幅值的影响规律。数值计算结果表明，当发射电流频率高于200Hz时，套管中的电磁场几乎完全被套管吸收，电磁波信号无法穿过套管进人地层；当套管厚度在4～7mm范围内变化时，接收信号幅值较强；随着套管相对磁导率的增加接收信号幅值单凋下降。研究结论可为普通井或套管井电磁测井解释及电磁测井仪器的研制提供理论依据。By calculating the electromagnetic field response of the receiver loop in the case of transmit coil and receiving coil with axial arrangements, the maximum transmitting frequency is determined and the rule of the influence of casing thickness, magnetic permeability and electrical conductivity is studied. The numerical results show that when the frequency of emission current is higher than 200 Hz, the electromagnetic field is almost absorbed by the casing, therefore electromagnetic signals can not pass through the casing into the formation. When the casing thick- ness is in the range of 4 - 7 mm, the received signal has greater amplitude. Furthermore, the higher the casing relative magnetic permeability, the lower the amplitude of received signal. This study can provide a theoretical basis for log interpretation and instrument development in general well or cased hole.

关 键 词：电磁测井 金属套管 磁导率 电导率 

分 类 号：P631.84[天文地球—地质矿产勘探]