瞬变电磁全波测井方法高密度采集面临的问题及对策  

Problems and countermeasures of high-density acquisition in transient electromagnetic full-wave logging

作　　者：沈建国 锡振强 盛晓斐 沈永进 SHEN JianGuo;XI ZhenQiang;SHENG XiaoFei;SHEN YongJin(School of Microelectronics,Tianjin University,Tianjin 300072,China;Beijing Huahui Test Technology Co.,Ltd.,Beijing 101313,China)

机构地区：[1]天津大学微电子学院,天津300072 [2]北京华晖探测科技股份有限公司,北京101313

出　　处：《地球物理学进展》2022年第3期1138-1147,共10页Progress in Geophysics

基　　金：国家重点研发计划“超高层建筑深基坑施工安全技术与装备研究”(2016YFC0802008)资助。

摘　　要：瞬变电磁全波测井是一种非接触式过套管地层电导率测量方法.在沿井轴方向连续记录瞬变电磁响应波形的过程中进行高密度采集,尽可能减小深度采样间距,可以获得丰富的纵向和径向地层电导率信息,从中提取出不同纵向、径向深度的地层电导率.由于响应波形时间较长,单次采集时间长、数据量大,传输周期长,采用等时激发,实际测井的深度采样间距呈现出随机分布.本文先通过实际测井数据展现了这一结果,简单分析了原因,结合几何因子讨论了深度采样间距对探测深度和纵向分辨率的影响.然后,介绍了瞬变电磁全波测井波形处理方法,用几何因子建立了不同深度采样间隔的处理方法和校正方法;最后结合瞬变电磁响应波形的特点提出了瞬变电磁测井仪器及其高密度采集的改进方案.Transient Electromagnetic(TEM)full wave logging is a non-contact method for measuring formation conductivity through casing.In the process of continuously recording TEM response waveforms along the well axis,high-density acquisition can be carried out to reduce the depth sampling spacing as much as possible,and rich vertical and radial formation conductivity information can be obtained,from which the formation conductivity of different vertical and radial depths can be extracted.Due to the long response waveform time,long single acquisition time,large amount of data and long transmission period,the actual depth sampling spacing presents a random distribution by isochronal excitation.In this paper,the result is shown by the actual logging data,the reasons are analyzed simply,and the influence of depth sampling spacing on the detection depth and vertical resolution is discussed combined with geometric factors.Then,the processing method of transient electromagnetic full wave logging waveform is introduced,and the processing method and correction method of different depth sampling interval are established with geometric factor;finally,according to the characteristics of TEM response waveform,the improved scheme of TEM logging tool and its high-density acquisition is proposed.

关 键 词：瞬变电磁测井 高密度采集 深度采样间距 几何因子 

分 类 号：P631[天文地球—地质矿产勘探]