径向非均匀介质中的电磁测井响应  

Electromagnetic logging response in radial heterogeneous media

作　　者：宋汐瑾[1] 任志平[1] 杨阳[1] 

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

出　　处：《西安石油大学学报（自然科学版）》2010年第1期61-64,共4页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金：国家863项目(编号:2007AA06Z217);西安石油大学科技创新基金(编号:2006-56)

摘　　要：通过求解圆柱坐标系中电场强度的赫姆霍兹方程,导出了径向非均匀介质中电磁测井的响应函数的一般表达式.数值计算结果表明,套管厚度的微小变化对电磁测井响应影响明显.不同电导率金属套管的电磁测井响应分析表明,套管电导率越高,接收线圈上的电场响应幅度越小.讨论了套管磁导率变化的电磁测井响应特征,结果表明:套管磁导率越高,电磁波信号越难穿过套管,响应信号幅度越小.因此,在套管井电磁测井技术中,应尽量选用非磁性或弱磁性套管.The general expressions of the electromagnetic logging response functions of in radial heterogeneous media are deduced by solving the Helmholtz equation of electric field intensity in cylindrical coordinate system.And the effects of the casing thickness on electromagnetic logging responses are analyzed.The computation results show that the little change of the casing thickness will produce an obvious effect on the logging responses.The numerical results of the casing pipe of different electrical conductivity show that the higher the electrical conductivity of the casing material,the lower the signal amplitude of the electromagnetic logging response,and that the higher the magnetic permeability of the casing material,the more difficultly the electromagnetic signal passes hrough the casing.So non-magnetic or low-magnetic steel pipe is superior to magnetic iron pipe.The research results in this paper can provide a theoretical basis for the logging interpretation and the optimization of instrument parameters in cased wells.

关 键 词：电磁测井 非均匀介质 金属套管 磁导率 电导率 

分 类 号：P631[天文地球—地质矿产勘探] TE937[天文地球—地质学]