Structural characteristics and hydrocarbon exploration prospects of the Doukala Basin, offshore Morocco

The Doukala Basin off the coast of Morocco is rich in hydrocarbon. However, there is a lack of systematic understanding of the structural evolution characteristics and geological conditions of hydrocarbon. Based on previous research results and combined with detailed seismic data interpretation, we summarized the structural characteristics, analyzed the structural evolution process and structural deformation mechanism of the Doukala Basin, and discussed the characteristics of hydrocarbon accumulation. Results show that the extensional deformation of the Doukala Basin is characterized by stronger deformation in the east and weaker in the west, and stronger in the south and weaker in the north. The salt structural deformation is characterized by stronger in the middle and weaker on both sides, and stronger in the south and weaker in the north. The compression deformation is characterized by uplift in the east and stability in the west. The Basin has the basic characteristics of “horizontal zoning and vertical stratification”. Regionally, from west to east, it can be divided into a salt-poor stable zone, a salt-rich diapir zone, and a salt-poor compression zone. On the cross-section, it formed a three-layered structure of “fault depression — uplift-depression alternation — depression”. The basin evolution went through a rift stage, a stable drift stage, and a lateral compression stage, and the migration of structural deformation and salt flow differences have caused spatial differences in basin structural deformation. In addition, the Doukala Basin has two hydrocarbon accumulation assemblages of the Silurian-Permian and the Jurassic-Cretaceous, of which the Lower Cretaceous oil and gas reservoirs above the salt layer are the key exploration targets in the study area.