There were several Cenozoic tectonic evolution stages, such as rifting, fault-sagging and thermal sagging, in Baiyun deep-water area, resulting in various depositional sequences, i.e. the fluvial-lacustrine facies of Wenchang Formation developed in multiple half grabens during rifting, the sequence of Enping Formation deposited in a large lake during fault-sagging, the shallow marine shelfdeep slope facies of Zhuhai Formation developed during the transition from fault-sagging to thermal sagging and the deep-water marine sequence deposited in an intraslope basin during thermal sagging after 23.8Ma. These sequences have formed a three-level (rift, fault-sag, sag) basin framework,and led to favorable conditions of source-reservoirseal assemblage in Baiyun deep-water area. This depositional evolution was controlled by tectonic evolution, paleo-geography, provenance and sea level fluctuation. As a main control on post-rifting marine deposition in Baiyun deep-water area,Baiyun movement from 23.8Ma to 21. 0Ma had migrated the provenances of paleo-Pearl River and the shelf-break zone in Baiyun deep-water area, resulting in a regressive-progradation sequence set of Zhuhai Formation and a transgressive-aggradation sequence set of Zhujiang Formation-Hanjiang Formation. In both sequence sets developed sandstones of large scale deep-water fans.%白云深水区在新生代经历了裂谷断陷、断拗、热沉降拗陷等构造演化阶段,相应发育了裂谷断陷期文昌组多个半地堑陆相河湖沉积,断拗期恩平组大型湖盆沉积、从断拗向热沉降拗陷过渡的珠海组海相浅水陆架一陆坡深水沉积,以及23.8 Ma之后的热沉降拗陷期海相陆坡内盆地深水沉积,形成了独特的多个盆地叠置的沉积充填模式和断陷-断坳-坳陷的三层盆地结构,从而在时间和空间上构成了有利的生储盖组合条件.构造演化、古地理、物源供给条件和相对海平面变化等多种因素控制了白云深水区的沉积充填演化;发生于23.8～21.0 Ma的白云运动,是白云深水区裂后海相沉积充填的主控因素,使得古珠江的物源体系和陆架坡折带发生迁移,形成了珠海组海退进积型与珠江组-韩江组海侵加积型层序组合,这两个层序组合均发育大规模深水扇砂岩.
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