【摘要】 松辽盆地三肇凹陷扶Ⅱ-Ⅰ组隐蔽性岩性油气藏埋藏相对较浅,油气资源极其丰富,已成为下一步致密油勘探、增储上产的重点目标区。三肇凹陷扶Ⅱ-Ⅰ组以浅水三角洲沉积体系为主,相带变化复杂,分流河道砂体构成扶Ⅱ-Ⅰ组的主体储层格架。通过53口井岩心精细观察,利用1 000多口测、录井等资料,分析三肇凹陷扶Ⅱ-Ⅰ组浅水三角洲平原分流河道砂体沉积特征,识别出11种岩相类型,根据不同基准面旋回,总结3种岩石相组合类型。研究表明,单一分流河道内部存在泥质、钙质以及含砾粉砂岩3种夹层类型,进而精细解剖单一分流河道内部建筑构型。利用分流河道砂体顶端拉平,建立同期河道砂体及夹层对比模型,从岩性、夹层类型以及测井曲线形态等方面进行对比,探讨了等时地层格架内近井距井间砂体同期分流河道的识别方法及分布规律。在上述砂体对比方法基础上,采用栅状图进行井间砂体对比,结合地震属性分析,刻画单一分流河道砂体平面展布特征,以期能够进一步为致密油藏水平井布置、勘探开发提供地质依据。更多还原

【Abstract】 Subtle lithologic reservoirs with shallow burial depth in the Ⅱ-Ⅰ Fms of Fuyu oil layers( FⅡ-FⅠ) are widely distributed in Sanzhao Depression,Songliao Basin,and are the major targets of tight oil exploration for reserve growth.The F Ⅱ-F Ⅰ in Sanzhao Depression are dominated by shallow water delta depositional systems featuring in complex change of sedimentary facies belt,and their main reservoir frameworks consist of distributary channel sandbodies. Based on detailed core observation of 53 wells and combining with logging data of more than 1 000 wells,11 types of lithofacies were recognized in the distributary channel sandbodies of FⅡ-FⅠ in study area,and they were grouped into 3 lithofacies associations according to different datum level cycles. There are three types of interlayers in single distributary channel,including muddy interlayer,calcareous interlayer and conglomeratic siltstone,by which the internal architecture configuration of single distributary channel sand body was further analyzed. Comparison models for cotemporaneous channel sandbodies and interlayers were built through flattening of the tops of distributary channel sandbodies and were used to compare the sandbodies in respects of lithology,types of interlayer and shapes of logging curve. Methods were proposed for identifying the interwell cotemporaneous channel sandbodies between wells with small spacing within the sequence stratigraphic framework and the distribution of sandbodies was also discussed. Based on the comparative method above,combining with comparison of sandbodies by fence diagram and seismic attribute analysis,the distribution characteristics of single distributary channel sandbody were described,providing a geologic foundation for tight oil exploration and development.更多还原