This work deals the Historical Biogeography`s analysis of corals and bryozoans in the Pirabas Formation, as well as identify their biological events, correlated with geological events that may have led to the accumulation of hydrocarbons in the coastal basins of northern Brazil. The geological evolution of the area in the Barremian and Aptian times was marked by the rifting phase in the Brazilian equatorial margin, widening the mouth of the Amazon Basin and the grabens Gurupi and Marajó Basin. During the Albian the continuity of the rifting supports the formation of Pará-Maranhão and Barreirinhas basins and Atlantic Ocean. The integrated analysis of geohistory of scleractinian corals and bryozoans registered in the Pirabas Formation helps in recognize its phylogenetic, and the greatest morphoanatomic innovations as response to Earth's geodynamics. The carbonates reservoir rocks included in the Ilha de Santana (Para-Maranhão Basin) and Amapá (Foz do Amazonas and Caciporé basins) formations, tertiary deposits correlated with the Marajó (Marajó Basin), and Pirabas formations. The data collected suggest that the rapid biotic proliferation of coralinofauna and briozoofauna occurred during the Cretaceous also did affect the chlorophyceae and, coralline algae, foraminifera, fungi and dinoflagellates. The rich record of these invertebrates in Pirabas Formation suggest that the new pulse of corals and bryozoans can be used as a guide for exploratory oil, because the age of the biological events, deposition and biotic content of carbonate rocks assigned as a reservoir in the Pará-Maranhão and Foz do Amazonas sedimentary basins, are syncronous.
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