摘要
井间电磁测井技术测量井间地层电磁波传播特性,通过正反演获得井间电阻率分布信息,由此揭示地层油气水的分布信息.井间电磁接收是井间电磁测井技术中一项重要内容,是开展井间电磁成像测井系统研制中必须攻克的难题之一.本文通过对比磁反馈与无磁反馈两种天线接收幅度与相位特性,发现磁反馈接收天线频带平稳无相位跳变点,相比无反馈天线具有明显优势.在磁反馈天线的基础上,本文分析不同天线磁芯、不同天线缠绕方式对天线幅频特性的响应,发现这些参数均对天线幅频特性有不同影响,为天线设计与研制提供参考设计参数.在接收天线研究的基础上,采用噪声匹配放大、1/f滤波、工频压制、数字锁相放大、相敏检波等软硬件处理技术,进一步降低噪声,提高接收精度和灵敏度.为有效开展井间同步发射与接收采集,采用高精度时间同步技术,提高同步与电磁波相位提取的精度.针对接收线路与系统中存在的误差,采用两距离井间电磁刻度方法进行压制.井间电磁接收样机研制完成后,分别在现场进行井下噪声测试、非金属套管井间、金属套管井间等系列井间电磁接收测量实验,研究与实验结果表明:本文所研究的井间电磁接收技术可实现500 m以上大井距和双层金属套管井间测量.
The cross well electromagnetic logging technology measures the electromagnetic propagation characteristics of the formation between wells,and obtains the cross well resistivity distribution information through forward and reverse processing, so as to reveal the distribution information of oil, gas and water in the formation. Cross well electromagnetic reception is an important part of cross well electromagnetic logging technology,and it is one of the difficulties that must be solved in the development of cross well electromagnetic imaging system. By comparing the receiving amplitude and phase characteristics of magnetic feedback and nonmagnetic feedback antennas,it is found that the magnetic feedback receiving antenna has a stable frequency band and no phase jump point,which has obvious advantages over the non feedback antenna. Based on the magnetic feedback antenna, this paper analyzes the response of different cores and different winding methods of the antenna to the amplitude frequency characteristics. It is found that these parameters have different influences on the amplitude frequency characteristics of the antenna,which provides reference parameters for the antenna design and development. On the basis of the research of receiving antenna,software and hardware processing technologies such as noise matching amplification,1/f filtering,power frequency suppression,digital phase-locked amplification,phase sensitive detection are adopted to further reduce noise and improve receiving accuracy and sensitivity. In order to effectively carry out cross well synchronous transmission and receiving acquisition,high-precision time synchronization technology is adopted to improve the accuracy of synchronization and electromagnetic phase extraction. Aiming at the errors from the receiving circuits and the system,the two spacing calibration method is used. After the development of the cross well electromagnetic receiving prototype,a series of cross well electromagnetic receiving experiments such as downhole noise tests,nonmetal casing tests,metal casing tests were carried out on site. The research and experimental results show that the cross well electromagnetic receiving technology studied in this paper can realize the cross well measurement of long spacing wells of more than 500 meters and double-layer metal casing.
作者
晁永胜
臧德福
姬勇力
王华雄
张庆乐
纪祝华
任燕敏
CHAO YongSheng;ZANG DeFu;JI YongLi;WANG HuaXiong;ZHANG QingLe;JI ZhuHua;REN YanMin(GEO-MWD/LWD and Logging Research Institute,SINOPEC MATRIX Corp,Qingdao 266071,China;UPC-Matrix Research Institute on Industry-Education Integration,Qingdao 266580,China;The 22nd Research Institute of CETC,Xinxiang 453003,China)
出处
《地球物理学进展》
CSCD
北大核心
2023年第1期147-158,共12页
Progress in Geophysics
基金
国家自然科学基金项目“深海热液系统孔域原位多参数探测-观测装置”(42127807)
国家重点研发计划“城市地下空间精细探测技术与开发利用研究示范”(2019YFC0605101)
中国石化科研项目“井间电磁成像系统研制及其处理解释方法研究”(JP16027)联合资助。
关键词
井间电磁
磁反馈天线
时间同步
井间电磁刻度
数字信号处理
Cross well EM
Magnetic feedback antenna
Time synchronization
Cross well EM calibration
Digital signal processing
