为厘清苏北盆地王龙庄油田阜宁组三、四段砂体成因及发育规律,指导油气的高效勘探开发,采用岩心、测井、录井及分析化验等资料,对研究层段的沉积相进行识别,并阐明其时空演化规律;在此基础上,进一步分析有利砂体所在,并揭示其空间分布规律.分析表明:其泥岩的颜色以灰绿色、浅灰色为主,还可见薄壳腹足、双壳类等化石,指示浅湖沉积背景;砂体粒度细、成熟度高,发育小型交错层理、反粒序等沉积构造,是曲流河三角洲的典型沉积特征.共识别出曲流河三角洲前缘、前曲流河三角洲及浅湖3个亚相,以及水下分流河道、支流间湾等6个微相;湖平面经历了“下降-上升-再下降”的旋回变化,随之形成了一套“进积-退积-再进积”的多旋回沉积体,演化规律十分清楚.水下分流河道砂体是最有利的砂体,且其空间分布规律受到沉积演化的控制;E1f33和E1f4小层沉积时期是有利砂体最发育的时期.%In order to clarify the origin and developing rules of sand body of the third and fourth member of Funing Formation of Wanglongzhuang oilfield,and then guide the efficient exploration and development of oil and gas,its sedimentary facies type has been recognized,and its evolution rules has been clarified.Moreover,the position of favorable sand body has been analyzed and its spatial distributary pattern has been revealed through using the core,logging and analytical data.The results showed that the colors of mudstone mainly were grey-green and light-grey color,and shell gastropods and bivalves fossils were common,which indicated the shallow lake environment.Moreover,a fine grain size,high maturity and small cross-bedding and reverse grading of the sand body were the typical sedimentary patterns of meandering river delta.Three subfacies and six microfacies has been identified;and a series of cyclical sedimentary body of "progradation-retrogradation-progradation again" has been formed by the cyclical changes of "fall-rise-fall again" of the lake level.Sand body developping in the underwater distributary channel was the most favorable one and its spatial distributary rules was controlled by the sedimentary evolution;the period of E1f3 and E1f4 should be the most developmental periods of favorable sand body.
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