Analysis of the geological structure and oil-gas exploration potential of the Morondava Basin in Madagascar

The Morondava Basin in western Madagascar is one of the basins with relatively low oil and gas exploration intensity on the east coast of Africa. Based on seismic and geological data, we adopted balanced cross-section and basin modeling technologies to analyze the basin's geological structure, tectonic evolution, thermal evolution, and basin-forming mechanism, as well as its oil and gas exploration potential. Results show that: (1) vertically, the basin has a typical double-layered structure, i.e., faulted in lower part and depressed in upper part; horizontally, it exhibits obvious east-west zonation characteristics; (2) the formation of the basin is closely related to the breakup of the Gondwana supercontinent and the multi-stage transformation of the regional tectonic stress field, and it has experienced 3 key stages of tectonic evolution. Further analysis on oil and gas exploration potential indicated that the basin had the condition for continuous hydrocarbon supply from multiple sets of source rocks, and developed multiple sets of high-quality reservoirs and favorable reservoir-cap combinations. However, affected by the strong late-stage onshore tectonic transformation, the early oil and gas reservoirs have been damaged. Comprehensive analysis revealed that the offshore area of the Morondava Basin has good oil and gas exploration prospects.