Deep-water sedimentary basins of passive margins are a hot field in petroleum exploration and sedimentology research. Based on the study of Niger Delta basin and Baiyun sag, Pearl River Mouth basin, making use of high-resolution 3-D seismic data, the deepwater gravity flow depositional elements and deep-water depositional systems are discussed and three conclusions are made; ( 1 ) Deep-water gravity flow depositional systems in different basins vary in general distribution, however they are all composed of basic depositional elements which are mass transport deposits, submarine channel, and lobe. (2) Due to the differences in gravity flow supply, continental slope topography, equilibrium profile, accommodation, and deposition process, there are significant differences in the deep-water gravity flow depositional systems and their system stack styles in passive margin basins. (3) When the deep-water gravity flow depositional elements are identified and characterized, the main controlling factors should be taken into account for the deepwater gravity flow depositional system. It is unrealistic to accurately summarize and predict the gravity flow depositional system with any single model.%被动陆缘深水沉积盆地是深水油气勘探和沉积学研究的热点领域.本文基于尼日尔三角洲西部深水区与珠江口盆地白云深水区的高分辨率三维地震资料开展深水重力流沉积单元和沉积体系研究.主要取得3个方面的认识:①尽管两个地区所发育的重力流沉积体系差异较大,但基本沉积单元是相同的,均由块体搬运沉积体系、深水水道和朵体组成.②尽管不同被动陆缘深水沉积盆地所发育的深水重力流沉积单元基本相同,但由于重力流供给、海底地形、陆坡均衡面以及可容空间和沉积过程等因素的差异,深水重力流沉积体系以及沉积体系叠置样式存在较大的差异.③进行深水沉积单元的识别和表征研究的同时,应加强深水沉积体系控制因素研究,而不能简单地套用某种深水沉积模式.
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