南堡凹陷东营组层序地层格架与沉积体系

通过对地震、岩心、钻、测井资料综合分析，将东营组划分为1个二级层序、3个三级层序。并根据初次湖泛面和最大湖泛面特征将每个层序进一步划分为低位域、湖侵域和高位域等三个体系域。层序格架和展布受凹陷结构和断裂活动影响，高柳断层以北地区东营组沉积厚度薄，且后期剥蚀严重。南部滩海地区的各层序完整，厚度相对稳定。在层序格架内分析了南堡凹陷东营组的沉积体系，东北部陡坡带以发育水下扇、扇三角洲为主，西北部和南部缓坡带发育三角洲、扇三角洲和辫状河三角洲。层序界面、准层序（组）叠加样式以及沉积体系空间展布均受到构造活动的控制，强构造活动期形成退积式叠加模式，而弱构造活动期对应进积式叠加模式。对层序发育和油气成藏条件分析认为层序1低位域的扇三角洲砂体和层序2中的浊积砂体为寻找岩性油气藏的有利部位。

Sequence Framework and Sedimentary Facies of Ed Formation in Paleogene,Nanpu Sag,Bohai Bay Basin

Comprehensively using the drilling,logging and seismic data,based on the boundary characteristics of the sequence systems tract,sequences of Ed Formation in Paleogene in the area of Nanpu sag were classified.Ed Formations were divided into three sedimentary sequences.By tracing MFS and FFS,lowstand,transgressive and highstand system tracts was ascertained.The basin palaeogeography and fault activity have influenced on framework and distributions of the sequence.On the area of hanging-wall of Gaoliu fault,Ed Formation was thin and eroded hardly,especially in Liuzan region.The centre of sequence thickness was located on Linque sub-sag,thickness is more than 2500m.While on the land,average sequence thickness is 1800m.Depositional systems were analysis on sequence stratigraphic framework.On the slope region in the northeast,alluvial fan and fan-delta were mainly depositional systems.And braided river-delta,fan delta and delta were distributed in the northwest and south slope.Tectonic activities were critical controlling factors on sequence system boundary;stack mode and distribution of deposition system.Strong active fault make retrogradation mode,and inertia fault make progradation.The favorable lithological traps are located mainly on fan-delta in the lowstand system tracts of sequence1 and on turbidite fan in the sequence 2.