Abstract:

Based on the seismic interpretation and reservoir characteristics, combined with previous studies on the formation and evolution of the Atlantic, we analyzed the structural characteristics, tectonic evolution and petroleum geology of Para-Maranhao Basin in northeast Brazil, then summed up its accumulation mode. The Para-Maranhao Basin can be divided into four units, which are Marajo Block, Para-Maranhao platform, Ilha de Santana platform and deep sub-basin. The basin is a typical passive continental margin basin, which experienced three tectonic evolutions, i.e. rift stage, transform stage and drift stage, forming different sedimentary styles and lithologies. The accumulation combination is proven that the Albian Caju Group is source rock, which is good for hydrocarbon generation, and the Late Cretaceous Ilha de Santana Group is good reservoir, which is fractured sandy platform carbonate. The traps associated with thrust are well developed in the deepwater fold and thrust belt. The Paleogene Travosas Group is proven to be source rock in the peripheral basin, so it is a potential source rock in this basin. Besides this, the Travosas Group turbidite sandstone is a good reservoir. In summary, this area is thought to have potential for hydrocarbon accumulation.

Key words: structural characteristic, petroleum geology, hydrocarbon accumulation, Para-Maranhao Basin, northeast Brazil