Two Types Plays and Exploration Potentials in the Equatorial Atlantic Transform Passive Continental Margin Basin
The transform passive continental margins are basins controlled by oceanic transform faults. The basin structure has the features of narrow shelf steep slopes and relatively developed rift and drift sequences. Based on the analogy of the conjugate basins on both sides of the equatorial Atlantic, Both rift-faulted blocks and drift-period turbidite sand bodies have good hydrocarbon exploration potential. Using PlateWizard software to reconstruct the paleo-plate with the basin boundary and oil field in different ages of early Cretaceous period (100-140 Ma), the Potiguar and Ceara basins in the eastern South America are precisely conjugate with the Benin basin in West Africa, and the Barreirinhas basin is conjugated with Cote d’ Ivoire basin, which split by three transform faults. The conjugate basins have similar hydrocarbon accumulation conditions. There are also have two kinds of fault system, The strike-slip faulting system parallel to the transition fault and the extensional fault system perpendicular to the strike-slip fault. The basin slope steered by the strike-slip fault is very steep, and the fault is a high-angle fault with flower-shaped structure, and the extensional faults control the relatively slow edges of the continental shelf, developing several faulted blocks and relatively slow slopes, which are easy to form good faulted blocks paly and turbidite sand plays. Now, 1905MMB 2P recoverable reserves are found in rift sequence of Ceara and Potiguar basins. In 2014, Petrobars found that the Pitu oil field has an oil column height of 150 meters and a net oil layer thickness of 42 Meters, showing good exploration potential. The Beni basin should also develop rift sequences that are only in the early stages of exploration. Early Cretaceous rifting sequences are also developed through structural mapping, which should be the next key direction of exploration. The main discovered fields in the Ivory Coast of West Africa are the Cenomian-Turion turbidite sandstone with recoverable 2P reserves 2968MMB have been found until now. It is also suggested that the exploration potential of this type of plays should also be focused on in the Ceara and Barreirinhas basins in eastern Brazil.
AAPG Datapages/Search and Discovery Article #90325 © 2018 AAPG Europe Regional Conference, Global Analogues of the Atlantic Margin, Lisbon, Portugal, May 2-3, 2018