Petroleum geology characteristics and exploration directions in Espirito Santo Basin, Brazil

In recent years, a great discovery of petroleum has been made in the Santos and Campos basins; however, little has been made in the Espirito Santo Basin which is adjacent to the two basins. Exploration level of the basin is also low. We studied the sedimentary characteristics, tectonic evolution, source rock, trap and reservoir in detail, and found the petroleum distribution rules, main factors and modes of petroleum accumulation, in order to reveal petroleum enrichment regularity and point out exploration directions in the Espirito Santo Basin. The basin belongs to the passive continental margin basin group near the east coast of Brazil, successively experiencing rifting, transitional and drifting periods, and accordingly developing sub-salt, salt and supra-salt rock sequences. Influenced by the salt diapirism, the basin has formed a very different sub-salt and supra-salt double-layer structure, within which the sub-salt structure shows a propensity for "oblique board" zoning in general under the control of a rift system and the supra-salt structure, controlled by a gravity slide system, has developed various types of salt structure. The Aptian stage Cricare group Neocomian lacustrine shale is the best hydrocarbon source rock and petroleum is mainly distributed in the Upper Cretaceous-Neogene supra-salt turbidite sand, dominated by lithologic traps. The analysis shows that distribution of turbidite sand and migration pathways are the main controlling factors of petroleum accumulation, and the basin has 6 exploration directions at present, among which the near shore slope area is the most favorable for petroleum migration and accumulation.