摘要
利用解析法计算随钻方位电阻率仪器激发的电磁场随仪器方位变化的规律,研究其在地层界面预测中的应用。通过分析电磁波在各层介质中的反射和透射规律,得出了介质层中电磁波的解析表达式,计算了电磁波电阻率随钻测量的幅度衰减和相移,分析了定向电磁测量对地层界面的灵敏性,研究了地层相对倾角和接收天线倾角对电磁测量的影响。研究表明,线圈距和目的层厚度越大,定向电磁测量的探测范围越大;随着地层相对倾角和接收天线倾角的增加,定向幅度衰减在接近地层界面时的变化越明显,对地层界面的灵敏性增强。结合方位电阻率成像和定向电磁响应说明,在常规随钻电阻率仪器的基础上,增加倾斜接收天线,可以实现地层倾向的预测和判断。
The electromagnetic field of different azimuth was calculated by analytical method,and then its application for forecasting formation boundaries was researched. By studying the reflection and transmission of electromagnetic wave on each layer,an analytic expression for electromagnetic wave was obtained,which satisfied boundary condition of each layer,and then the amplitude-attenuation and phase-shift of electromagnetic wave resistivity logging were computed. The sensitivity to formation boundaries of directional electromagnetic measurements was analyzed,and the influence of formation relative dip angle and receiver antenna dip angle on directional measurements was also studied. The results showed that the directional detection range increased with the coil spacing and the thickness of target bed increasing. The change of directional amplitude-attenuation became more obvious with the formation relative dip angle and receiver antenna dip angle increasing when the tool was approaching formation boundary,and thus the sensitivity to formation boundaries increased. By combining azimuthal resistivity image with directional electromagnetic response,the results showed that adding tilt antenna to conventional logging while drilling resistivity tools,the formation boundaries could be accurately forecasted.
出处
《山东大学学报（工学版）》
CAS
北大核心
2015年第6期99-106,共8页
Journal of Shandong University（Engineering Science）
基金
国家自然科学基金资助项目(61475084)
关键词
磁偶极子
方位电阻率
倾斜天线
定向幅度衰减
定向相移
地层界面
magnetic dipole
azimuthal resistivity
tilted antenna
directional amplitude attenuation
directional phase shift
formation boundary
