过套管电阻率测井资料预处理方法研究

Data Pre-processing Method for Cased Hole Formation Resistivity Logging

近几年,随着电子技术的发展和油田中后期寻找剩余油分布的需要,过套管电阻率测井作为一种新技术迅速发展起来。该技术在套后剩余油监测、老井挖潜、油层水淹规律确定、油层生产动态监测等方面具有独特的优势,并取得了较好的应用效果。但在采集过程中其有效信号为纳伏级,套管、测量频率、测量电极距、水泥环、套管非均质性等都会使测量信号发生严重的畸变,在过套管电阻率资料预处理中必须对这些因素进行校正。本文针对俄罗斯ECOS-31-7过套管测井资料特点,分析了原始离散数据筛选方法、离散数据插值原则,探讨了套管非均质性、水泥环及固井质量校正方法。对实际过套管测井原始资料的处理效果表明,该处理方法有效可行。

With the recently development of electronic technology,the cased hole formation resistivity logging has been rapidly developed in order to discover the distribution of residual oil in the middle or late exploitation stage of the oilfields.The logging technology has many advantages that include the monitor of residual oil through casing,tapping potential of old well,the determination of submerged oil layer,and the production dynamic monitoring.They have all received quite good application effects.However,the effective signal during the acquisition process is in the level of nano-volt,the casing,measuring frequency,measured from the electrodes,cement mantle,and the heterogeneity of cased hole all will make measured signal distort,the cased hole resistivity data in the pre-processing must be corrected for these factors.Based on the logging information characteristics of the Russian ECOS-31-7,the filtering and interpolating methods for the original discrete data have been analyzed.Furthermore,the correction methods,such as the heterogeneity of casing,cement mantle,and cement quality,have been discussed.The processing results of the original data by means of actual casing measurements in the oilfield indicate that the method is feasible and effective.