河南省濮城油田南区沙二上4-7 砂层组沉积相研究

对濮城油田南区沙二上4—7砂层组进行超短期、短期、中期三级基准面旋回研究，认为该层段可划分为一个下降半中期旋回和8个短期旋回。在此划分的基础上，结合区域构造、沉积背景、岩心观察、取心分析化验和测井等资料，确认濮城油田南区沙二上4—7为气候炎热、蒸发强烈、湖面波动大的小型闭塞盆地内发育的湖退式三角洲前缘沉积，发育有水下分流河道、水下天然堤、水下分流间湾、河口坝、决口扇、远砂坝及滑塌砂体7种沉积微相。

Sedimentary facies studies of Sha'ershang 4-7 sandstone layers in the south block of Fucheng oilfield in Henan province

Through studies of three step (including extra short, short and medium periods) base level cycle in Sha'ershang 4-7 sandstone layers of Fucheng oilfield,the intervals can be divided into one decline half medium cycle and 8 short period cycles.On the basis of the above division,by integrating the data of regional structure,sedimentary setting,rock observation, core analysis and test, logging and so on,these intervals are determined to be lake regression type delta front sedimentation developed in hot climate with severe evaporation and in small enclosed basin with serious surge of lake surface. Furthermore the following 7 kinds of sedimentary microfacies are well developed:underwater distributary channel,underwater natural barrier,underwater distributary intermittent bay, river mouth bar,crevasse splay,far sand bar and slump sand body.