Abstract: The process of drilling mud filtrate invading into an oil/gas reservoir is related to invasion time after the bed was penetrated,hence the reading of a resistivity logging tool is a function as time.Prior resistivity inversion algorithms are based on an over-simple step-invasion model,so they cannot give a realistic invasion image,furthermore,the inversion results must be influenced by the ideal invasion model.The present inversion of time-lapse logging holds fluid-and formation-related parameters that control the dynamic invasion process in the model.Therefore,it is able to exhibit the dynamic characters of a realistic invasion process and provides more information for researchers to evaluate a reservoir.Since the present model is sensitive to the variation of saturation,mud property,drilling condition and so on,a reservoir can be evaluated through matching time dependent field logging data.Original water saturation(or true formation resistivity) and mud cake permeability are regarded as unknown parameters to be determined from the inversion routine.Field applications for dual-induction logging illustrate that the present model is a reasonable and efficient method for reservoir evaluation.

Key words: well logging, inversion, invasion, time, resistivity, saturation

摘要： 地层钻开后泥浆滤液侵入油(气)层是一个随时间变化的复杂过程,因此,测井仪器的响应是时间的函数.以往的电阻率反演算法均基于简化的阶跃式侵入模型,不能给出真实侵入过程的图象,反演结果也受到这一理想侵入模型的限制.时间推移感应测井动态反演模型计入了控制侵入过程的流体和地层参数,它能展示真实侵入过程的动态特征,为储层评价提供更为丰富的信息.该模型对流体饱和度的变化、泥饼性质、钻井条件等因素较为敏感,因而,可以通过按泥浆浸泡时间而记录的测井数据,反演原始含烃饱和度(或地层真电阻率),从而进行储层评价.现场应用实例表明,该方法可以有效地应用于时间推移双感应测井的解释.

关键词: 测井, 反演, 侵入, 时间, 电阻率, 饱和度