摘要
在层序地层学和沉积学理论指导下,依据地震反射终止关系(不整合界面特征),将珠江口盆地番禺4洼古近系文昌组划分为6个三级层序,不同层序的地层分布明显受断裂构造控制。根据地震反射内部结构和外部形态,识别出强振幅高连续楔状地震相、丘状地震相和前积反射地震相等。其中,楔状地震相主要分布在洼陷东侧边界断层下降盘,前积反射地震相主要分布在洼陷西侧的缓坡带。文昌组地震相在平面上具有不对称性,在垂向上具有较强的继承性。东沙隆起为研究区提供物源,在番禺4洼东侧边界断层下降盘发育大规模粗粒近岸水下扇和扇三角洲;西侧和南侧缓坡也均为研究区提供物源,并形成中小规模的多类型较粗粒三角洲。
Under the guidance of sequence stratigrapy and sedimentology, Wenchang Formation in Panyu 4 depression is subdivided into six third-order sequences based on the features of seismic reflection termination, and the distribution of sequence is significantly controlled by fault activity. The seismic facies, including high-amplitude and high-continuity wedge facies, hummocky facies, progradation facies, have been recognized based on the seismic internal reflection configuration and external shape. Controlled by basin texture and fault activity of Panyu 4 depression, wedge-seismic facies is mainly distributed in the downthrow side of boundary fault in the eastern depression, and progradation-seismic facies is mainly distributed in the gentle slope of the western depression. The distribution of seismic facies of Wenehang Formation is asymmetry in the plane and stongly inherited in the vertival profile. Large-scale coarse-grained nearshore subaqueous fans developed in the downthrow side of boundary fault of the eastern Panyu 4 depression were supplied by Dongsha uplift, and the medium-small scale and multi-type deltas came from the west and south side of western gentle slope.
出处
《岩性油气藏》
CSCD
2014年第4期1-8,共8页
Lithologic Reservoirs
基金
国家科技部油气重大专项"岩性地层油气藏沉积体系
储层形成机理与分布研究"(编号:2011ZX05001-002-01)
国家油气重大专项"海洋深水区油气勘探关键技术"(编号:2011ZX05025-005-02)联合资助
关键词
层序格架
沉积体系
古近系
文昌组
番禺4洼
珠江口盆地
sequence framework
depositional system
Paleogene
Wenchang Formation
Panyu 4 depression
the Pearl River Mouth Basin
