Tectono-sedimentary Evolution and Petroleum Systemsof the Deepwater Basin along South Atlantic Ocean Margin
南大西洋深水盆地的构造沉积演化及含油气系统

The South Atlantic Margin Basins (SAMB) are the deepwater E&P hot areas of the world, whose tectono\|sedimentary and hydrocarbon conditions are controlled by the rifting and continued drifting of the South Atlantic, the change of weather and the sea level fluctuation. The structure evolution of SAMB can be divided into the prerift, rift, transitional and drift periods, and the drift period can be further divided into the marine transgressive and marine retrogressive periods. The terrestrial river, lacustrine and delta depositional systems were developed in the rift period, the Aptian evaporite rock was developed in the transitional period, and the carbonate and deepwater clastic rock systems were developed in the drift period. The SAMB petroleum systems can be divided into the presalt rift and postsalt drift petroleum systems by the Aptian salt layer, the source rock of the presalt rift petroleum system is lacustrine shale, its reservoir is the river, delta and shoreland sandstone, and the transitional salt is its cap rock; the source rock of the postsalt drift petroleum system is marine shale and the secondary migration of the rift continental source rock, the turbidite is the major revervoir, the cap rock is shale, and the late Cretaceous marine source rock is dominant in this layer. The diverse rifting and drifting of the South Atlantic Ocean controlls the sequence development, evaporates distribution and hydrocarbon potential of the SAMB.