针对古城油田泌123和泌124区块核三段Ⅳ砂组聚合物窜流严重,注采结构调整难度大的特点,基于岩心、测井、粒度等资料识别沉积相标志,对其沉积微相进行精细研究.研究区核三段Ⅳ砂组为三角洲前缘亚相沉积,主要发育水下分流河道、水下分流间湾、前缘席状砂、河口坝、远砂坝、河道侧翼和浅湖7种沉积微相.在湖平面上升时期物源供给充足,水下分流河道砂体在研究区分布范围明显减小,三角洲前缘中心部位发育叠置的主河道砂体组合、水下分流河道—河道侧翼砂体组合,向湖方向逐渐变为叠置的河口坝—远砂坝砂体组合；在三角洲前缘末端,沉积微相垂向上主要表现为水下分流河道—河口坝—前缘席状砂微相的正韵律构成的退积序列.水下分流河道、河口坝和河道侧翼微相砂体储层物性较好,前缘席状砂和远砂坝微相砂体厚度较小,储层物性较差,水下分流间湾和浅湖微相砂体不发育.%The structure is complicated in the block Bi 123-124 of the Guchen oilfield, and the reservoir is controlled by the lithology and structure. The crossflow is very serious in the study area, and the adjustment of the injection and production is difficult. On the basis of the data of core, well log, grain size, we identify the signs of sedimentary facies, and study the micro-facies of the reservoir sedimentary facies. The result shows that the Ⅳ sandstone layer of the second member of He Formation has developed delta front subfacies deposit, which can be divided into six types of sedimentary microfacies and creeping turbidite sandbody. The sedimentary microfacies include subsea distributary channel, river flank, mouth bar, distal bar, front sheet sand and distributary inter channel. The shape and distribution and superposition of the reservoirs sand are analyzed, so we can find that the subsea distributary channel and mouth bar are the favorable facies belts of the study area. All of above proofs that the oilfield in the studied is controlled by the structure and lithology. The result of the study can provide geological basis for the next step of the adjustment of the exploration.
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