【摘要】 利用地震、测井及录井资料,采用回剥技术及断失量的趋势分析方法,恢复了古近系沙三段中亚段沉积时期青东凹陷的构造—古地貌,阐明了构造—古地貌对沉积体系的控制.受郯庐断裂及其派生断裂的控制,古近系沙三段中亚段沉积时期青东凹陷呈现整体沉陷,为一东断西超的箕状断陷,凹中发育3个近东西向的次隆,将青东凹陷分隔为4个次洼,由南至北,次洼的规模逐渐扩大.受构造-古地貌的控制,沙三段中亚段青东凹陷的东部发育扇三角洲,西部和南部发育辫状河三角洲.三角洲沉积体系的主体发育部位明显受次洼的控制.由于凹陷规模小,物源供应充分,扇三角洲和辫状河三角洲的砂质沉积不同程度下超于中部次隆之上,由于次隆地带水浅浪强,形成规模不等的砂质滩坝.中部次隆规模较大,在缺少陆源碎屑供应的地带,发育钙质浅滩和泥滩.发育于东部断坡带的三角洲砂体,发育于西部斜坡带的辫状河三角洲砂体,以及发育于次隆地带的砂质滩坝砂体均具有较好的储集条件和较好的圈闭背景,是油气勘探的重要目标.更多还原

【Abstract】 Based on seismic,log curves and logging data,we adopted the analysis of back stripping technology and the trend analysis of faulted strata amount,the tectonic-paleogeomorphic of Palelgene Es3M in Qingdong Sag was restored,and tectonic-paleogeomorphic controlled on depositional system has been clarified.Controlled by Tancheng-Lujiang fault and its derived faults,Qingdong sag appeared as overall subsidence in Paleogene Es3M was a half graben which eastern boundary is Tancheng-Lujiang fault.There were 3 sub-uplifts,4 sub-sags developing in the sag nearly east-westward.The scale of the sub-sags getting larger and larger from south to north.Controlled by tectonic-paleogeomorphic,Qingdong sag of Paleogene Es3M developed fan delta depositional system in its eastern part near fault boundary and braided river delta depositional system in its western and southern part on the gentle slope.The main part of delta depositional system was obviously limited by sub-sags.Due to the small scale and sufficient sediment supply of Qingdong Sag,sandy sediments of fan delta and braided river delta showed downlap on sub-uplifts in different degree.The sandy beach and bars developed in different scales in sub-uplifts resulted from the shallow water and strong waves.Fan-delta sandy body of fault steep slope belt in eastern part,braided river delta sandy body of gentle slope belt in western and southern part and sandy beach and bars developed in sub-uplifts,which have good reservoir conditions and trap backgrounds,are the main target of oil and gas exploration.更多还原