Abstract:
The Great Campos Basin is a salt rich oil and gas basin, with significant discoveries made in recent years in the pre-salt layers, while the post-salt layers are in a low exploration valley. In order to clarify the remaining exploration potential of the post-salt strata in the Great Campos Basin, a systematic analysis was conducted on the control effect of salt structural deformation on the stratigraphic structure, sedimentary evolution, and hydrocarbon accumulation of the post-salt strata. The results are as follows: under the control of salt structure deformation, the post-salt layers develop detachment salt raft zone, diapir salt ridge zone, and nappe salt wall zone from west to east. The deformation of salt structures has restricted and transformed the deep water sedimentation of the post-salt drift strata. Early-stage salt structure deformation generally plays a limited role in overflow, guidance, and shielding of late-stage deep-water sedimentation, while late-stage salt structure deformation generally plays a transformation role in diapir and cutting of early-stage deep-water sedimentation. The deformation of salt structure provides traps and migration pathways for the hydrocarbon accumulation in post-salt strata. Tectonic stratigraphic traps related to salt rock roll are generally developed in the detachment salt raft belt, mainly including rollover anticlines traps, stratum pinch out traps and fault block traps; The diapir salt ridge zone mainly develops structural traps related to salt rock diapirs, such as salt top anticline traps, salt flank barrier traps, and turtle back anticline traps. Salt windows and salt related faults that have been in an open state for a long time constitute the dominant channels for oil and gas migration.The research findings provide significant reference value for guiding the next-phase oil and gas exploration in the Great Campos Basin.