歧南斜坡沙一段中部重力流水道优质砂体分布与演化

Distribution and evolution of high-quality sand bodies of gravity flow channel in the middle Member 1 of Shahejie Formation in Qinan slope,Bohai Gulf,China

以沉积岩石学与地震沉积学为指导,充分利用岩心、测录井、地震、物性等资料,对渤海湾盆地歧南斜坡沙一段中部砂体开展细分地层对比,探讨砂体分布规律及优质砂体主控因素;利用正演技术和反演技术,刻画优质单砂体,研究优质砂体发育区分布与演化特征。提出将沙一段中部细分为4个砂组,并确定了主力砂组;受南部埕宁隆起和Ⅲ级坡折带控制,中斜坡发育重力流水道,分布东西两支砂体带;岩性对物性控制作用明显,中细砂岩物性好。歧南斜坡区沙一段中部重力流水道优质砂体具有东西两支、三期展布、四个优质砂体发育区"左右迁移,此消彼长"的分布与演化特征。

Data of drilling cores,well logging,seismic information and physical property are used to correlate the sand bodies of mid Member 1of the Shahejie Formation in Qinan slope,Qikou sag of Bohai Gulf,and to discuss the distribution regularity and controlling factor of high quality sand body.Meanwhile,forward and inversion techniques are utilized to delineate the high quality single sand body and study its distribution and evolution characteristics.It is showed that the mid Member 1 of Shahejie Formation can be subdivided into 4sand groups and the main sand group is controlled by Chengning.Two gravity flow channels develop in the middle slope and two sand body belts occur in the west and east area.Lithology plays an important role in the physical property and the middle sizesandstone is of the best physical property.The east and west sand bodies distribute as 3stages and their distribution and evolution are characterized by left-right shift and mutual growth and decline relationship.