【摘要】 综合应用岩心、测井和地震资料,对渤海BZ25油田新近系明化镇组下段砂体进行了构型解剖,探讨浅水三角洲前缘指状砂坝内部的沉积微相组成,分析指状砂坝的宏观分布及内部构型特征。浅水三角洲前缘指状分支砂体为指状砂坝沉积,由河口坝、坝上分流河道以及天然堤组成,分流河道下切河口坝,薄层天然堤则披覆于分流河道两侧的河口坝之上。指状砂坝平面上多呈弯曲状,向盆地方向弯曲度有所增加,内部分流河道由深切河口坝型到浅切河口坝顶部型转变。研究区指状砂坝宽厚比为25～110,宽度与厚度呈一定双对数线性正相关关系,并受控于基准面旋回变化。针对指状砂坝,在注水开发方式下,应避免同一分流河道内注采的开发方式,并指出指状砂坝内分流河道的中上部及注采井未钻遇的河口坝砂体为剩余油挖潜的重点。更多还原

【Abstract】 Core, well logging and seismic data were used to investigate sandbody architectural characteristics within Lower Member of Minghuazhen Formation in Neogene, Bohai BZ25 Oilfield, and to analyze the sedimentary microfacies, distribution and internal architecture characteristics of the bar finger within shoal water delta front. The branched sand body within shoal water delta front is the bar finger, consisting of the mouth bar, distributary channel over bar, and levee. The distributary channel cuts through the mouth bar, and the thin levee covers the mouth bar which is located at both sides of distributary channel. The bar finger is commonly sinuous and its sinuosity increases basinward. The distributary channel changes from deeply incising the mouth bar to shallowly incising top of the mouth bar. The aspect ratio ranges from 25 to 50 and there is a double logarithmic linear positive relationship between the width and thickness for the bar finger, which is controlled by base-level changing in study area. For the bar finger, injection and production in the same distributary channel should be avoided during water flooding development. In addition, middle-upper distributary channel and undrilled mouth bar are focus of tapping remaining oil.更多还原