A review of the evolution and petroleum potential of the Bongor Basin, Chad

This study provides an overview of the tectonic evolution, stratigraphy, structural framework, petroleum systems, and hydrocarbon potential of the Bongor Basin. The development of the basin’s structural zone, a highly inverted Meso-Cenozoic rift basin influenced by the Central African Shear Zone (CASZ), occurred in five distinct phases. The main characteristics of the basin are landslides and inversion formations. Most of the primary rock assemblage in the basin consists of Lower Cretaceous rocks. The main processes sculpting the basin's Lower Cretaceous rocks are faulting and inversion. The Lower Cretaceous P, M and K formations are considered possible sources of hydrocarbons due to their high organic content and varying degrees of thermal maturation. The Lower Cretaceous is marked by two transgressive-regressive cycles, leading to the deposition of fluvial, deltaic, braided, and fan-shaped sandstones and mudstones. The bedrock of the basin is composed of deep lacustrine mudstones containing type I and type II organic materials. The fault-related inversion structures in the basin include single-faulting, double-faulting and distributed Bloomeria faulting. According to our findings, reservoir rocks and cap rocks that have experienced multiple episodes of stacked rifting should be the main targets of erosion in the basin. Prospective research should focus on the possible discovery of shale oil and lithological reservoirs in the source rocks of high inversion basins, as this suggests that the Bongor Basin has considerable petroleum potential. Using a combination of regional thermochronological studies and apatite fission-track analyses, we also carefully record the temperature history of the Bongor Basin within the West and Central African rift system. Our study also demonstrates the complexity of the potential and difficulties of oil exploration and extraction in the Bongor Basin.