海安凹陷古近系沉积层序及对油气藏的控制  

Sedimentary sequences in Haian Depression and control on reservoir of the Paleocene

作　　者：冉怀江 司宝玲 陈方鸿 范乐元 

机构地区：[1]中国石油长城钻探工程公司解释研究中心,北京100101 [2]北京中油石油技术有限公司,北京100083

出　　处：《石油地球物理勘探》2012年第5期795-802,844+681,共8页Oil Geophysical Prospecting

摘　　要：通过岩心、测井、地震以及分析化验等资料,本文对苏北盆地海安凹陷古近系进行了层序地层分析以及沉积相识别,进而研究了层序沉积体系的分布配置关系,揭示了主要油气藏分布规律。研究认为,从古近系泰州组到三垛组的盆地断陷阶段,海安凹陷经历了仪征、吴堡、真武和三垛等四次较大的构造抬升运动,形成了3个二级层序,在二级层序格架内可分为7个三级层序、17个体系域,其中主要的含油体系域包括SQ1-1低位体系域、SQ1-2低位体系域、SQ1-3高位体系域、SQ2-1湖侵体系域及SQ3-1低位体系域等;主要含油体系域发育的沉积相类型主要有扇三角洲、河流三角洲、辫状河三角洲以及湖相等;层序地层格架内体系域的沉积特征及空间位置的差异形成了不同的有利生储盖配置:SQ1-1低位体系域生储盖组合、SQ1-2低位体系域生储盖组合、SQ1-3高位体系域生储盖组合、SQ2-1湖侵体系域生储盖组合、SQ3-1低位体系域生储盖组合等。Using data from cores,well logging,seismic and core enperiment,the sequence stratigraphy analysis and sedimentary facies identification of the Paleocene of Haian Depression in Subei Basin are conducted.The distribution and allocation relations of the sedimentary sequence system are obtained,revealing the distribution regularity of the major reservoirs in this area.The work shows that the Haian Depression had undergone four tectonic uplift movements(Yizheng movement,Wubao movement,Zhenwu movement and Sanduo movement) during the basin fault-depression stage from Taizhou Formation to Sanduo Formation periods,and 3 secondary-order sequences were formed.In those secondary-order sequence stratigraphic frameworks,the Paleocene of Haian Depression can be divided into 7 third-order sequences and 17 system tracts,and the main oil bearing system tracts include the lowstand system tract of SQ1-1,SQ1-2 and SQ3-1,the highstand system tract of SQ1-3,and the lake transgressive system tract of SQ2-1.There are 4 kinds of sedimentary systems identified in the main oil bearing system tract,including fan delta,river delta,braided delta and lake facies.The differences of sedimentary characteristics and the space location relationship of the system tracts cause the different matching relationship of favorable source-reservoir-cap assemblages,including the source-reservoir-cap assemblages of the lowstand system tract of SQ1-1,SQ1-2 and SQ3-1,the source-reservoir-cap assemblages of the highstand system tract of SQ1-3,and source-reservoir-cap assemblages of the lake transgressive system tract of SQ2-1.

关 键 词：海安凹陷 古近系 层序地层 沉积相 体系域 生储盖组合 

分 类 号：P631[天文地球—地质矿产勘探]