苏北盆地溱潼凹陷西斜坡阜三段沉积相研究

Sedimentary facies study of 3rd member Funing formation in western slope of Qintong depression,northern Jiangsu basin

通过综合分析溱潼凹陷西斜坡阜三段的岩石学、粒度分布、沉积构造及测井相特征,认为该区阜三段主要发育三角洲前缘及浅湖-半深湖沉积,三角洲前缘可进一步识别出水下分流河道、水下分流间湾、河口坝、远砂坝、席状砂5种微相类型。在此基础上,以单井相分析结果及小层划分为约束,绘制了台III、IV砂组各小层沉积微相平面展布图,发现阜三段砂体主要源自北部的三角洲朵体,具有分布广、岩性细的特点,蔡家堡-顾庄地区以水下分流河道沉积为主,华庄-叶甸-俞垛-边城地区则以河口坝-远砂坝-席状砂沉积为主,各小层沉积微相平面展布有所差异。

Through comprehensive analysis of 3rd member Funing formation in western slope of Qintong depression,northern Jiangsu basin,such as petrology,particle size distribution,sedimentary structures and logging facies characteristics,3rd member Funing formation is mainly developed with delta front and shallow lacustrine and semi-deep lacustrine sedimentary facies,and the delta front can be further divided into underwater distributary channel,underwater distributary bay,mouth bar,distal bar and sheet sand,these five micro- facies types.On the basis of this,constrained by analysis results of single well facies and sub-layers division,the plane distribution map of micro-facies of Tai-III and TaiIV sand groups have been drawn.The maps show the sand body of 3rd member Funing formation is mainly from northern delta lobes,with wide distribution and fine lithologic characteristics,Caijiapu-Guzhuang are is centered on underwater distributary channel sediments,while Huazhuang- Yedian- Yuduo-Biancheng area is centered on mouth bar- distal bar- sheeted sand sediments.Therefore,the sedimentary micro-facies of various layers are of some differences.