| Kwanza Basin, located in Angola and its adjacent offshore area along the West African coast, is a typical
passive continental margin salt-bearing basin. It comprises three major structural layers: pre-salt structural layer, salt
structural layer, and suprasalt structural layer. The pre-salt Cretaceous lacustrine carbonate rocks represent the primary
target for hydrocarbon exploration in the basin. The pre-salt structural layer exhibits a tectonic pattern of alternating
depressions and uplifts, which can be divided into the Inner Rift Zone, Central Uplift Zone, and Outer Rift Zone from east
to west. The hydrocarbon accumulation mechanism in pre-salt lacustrine carbonate rocks is characterized by "riftcontrolled source rocks, uplift-controlled reservoirs, salt-controlled seals, and high-quality reservoirs controlling
accumulation". The Central Uplift Zone, with well-developed basement uplifts, not only facilitates trap formation and
carbonate reservoir development but also serves as the migration pathway for hydrocarbons, making it the most favorable
area for pre-salt Cretaceous carbonate reservoir accumulation. The presence of high-quality reservoirs is critical for
successful exploration. Based on newly acquired seismic and drilling data, this study investigates the factors influencing
the differential distribution of pre-salt lacustrine carbonate reservoirs. The analysis further narrows down the prospective
exploration areas for subsalt hydrocarbon plays in the Kwanza Basin to the northern part of the Central Uplift Zone,
providing guidance for regional evaluation and exploration target selection. |
