Abstract: Based on the study of its actual well log data,logging attributes and water-flooding mechanism of the study area,the grit water-flooding reservoir can be identified qualitatively by using GR,SP,DT,ML and RT curves.The quantitative identification indexes include the following parameters:gamma ray relative value,ΔGR,is below,the middle value of particles is over 0.24,and the travel time DT is less than 260μs/m.In the process of water-flooding,reservoir porosity and permeability increase,and the coefficient of pore structure reduces,and wettability turns from hydrophobicity or neutrality to weak to strong hydrophicity,and the Archie parameters such asm andnreduce as the resistivity of formation water increases.The salinity ratio of injecting water to in-situ formation is one of the major factors influencing on reservoir resistivity during water-flooding stage.Due to the different salinity of injecting water,relations between formation resistivity and water saturation show nonsymmetrical shapes of "U","L" or "∽".The study results are very helpful for log interpretation of waterflooding formation and establishment of adjustment plan.

Key words: grit reservoir, water-flooding formation, logging data, water-flooding mechanism, resistivity, quantitative identification

摘要： 对研究区块砂砾岩储层的实际测井资料、水淹特征和机理进行了研究,结果表明,利用自然电位(SP)、自然伽马(GR)、声波、微电极、电阻率测井曲线对砂砾岩储层进行定性识别。定量识别指标为:自然伽马相对值ΔGR<0.15,粒度中值M_d>0.24mm,声波时差DT<260μs/m。在储层的水淹过程中,储层的孔隙度和渗透率增大,孔隙结构系数减小,润湿性由中性偏亲水向弱亲水、亲水、强亲水方向转化,Archie参数m和n随地层水电阻率的增大而减小。其中,注入水矿化度与原始地层水的差别和有效泥质含量(阳离子附加导电性)是控制储层水淹过程中电阻率变化的主要因素之一。水驱过程中岩石电阻率R_t与含水饱和度S_w的关系随注入水矿化度与原始地层水的差别表现出不同的关系。在注入淡水条件下,根据注入水矿化度的不同,R_t与S_w之间的关系可呈现出非对称的“U”、“L”、或“∽”曲线特征。该研究结果有助于砂砾岩水淹层的测井解释和制定调整方案.

关键词: 砂砾岩, 水淹层, 测井, 水淹特征, 水淹机理, 电阻率, 实验研究