Abstract:

The study on topography and sedimental style of continental slop in Niger delta and Qiongdongnan Basin is important to exploration.In this paper,the seismic data are used to analyze topography and sedimental style of deepwater slope in Niger delta and Qiongdongnan Basin.As shown in this paper,the main reasons for the absence of gravity thrust folds on continental slop in Qiongdongnan Basin are there are less plastic shale and relative scarce sources;there are differences in structure style and sedimental pattern between the two areas.The structural traps or structure-subtle traps will become main targets of the deepwater exploration in Niger delta.But,attention should be payed to subtle traps in Qiongdongnan Basin.Model of dichotomy in sequence evolution is built up.The model can be meaningful for hydrocarbon hunting and cap rock evaluate ration in deepwater environment.

Key words: passive continental margin, continental slope, gravity thrust structure, gravity flow, sequence stratigraphy, northern south China sea, Niger delta