一种新的电成像测井地层倾角校正方法

摘要

Because of the small investigation radius of electrical imaging logging method,it can reflect strata information around the wellbore and extract formation dip.However,in the inclination angle calculation,the well diameter or a fixed electrical diameter correction to compensate is used,resulting in large calculation result.In this paper,the relationship between the electrical diameter correction and the formation resistivity is established by studying the effect of such factors as borehole mud,wall rock contrast with formation and formation dip on the electrical diameter correction.In practical application,the amount of correction based on the resistivity information of different measuring points is used to compensate the well diameter to get more accurate formation dip.The results of the ideal model test and the actual data processing show that the proposed method further improves the accuracy of the calculation of formation dip and can provide reliable information of stratum for the geological explanation with the electrical imaging data.%电成像测井方法由于探测深度浅,能够很好地反映井壁附近的地层信息,非常有利于地层倾角的提取;但在倾角计算中,大多直接采用井径值或者使用一个固定的电直径校正量进行补偿,导致计算的倾角值偏大.通过研究井眼钻井液、围岩与地层对比度以及地层倾斜等因素对电直径校正量的影响,建立了电直径校正量与地层电阻率的链表关系;实际应用中,由不同测量点的电阻率信息查询链表获得相应的校正量并对井径进行补偿,可以获得更加准确的地层倾角.地层理想模型检验和实际井资料处理效果表明,本文方法可进一步提高电成像测井地层倾角计算精度,能够为电成像资料的地质解释提供更加可靠的地层产状信息.