Foz do Amazonas Basin – A case for oil generation from geothermal gradient modelling
With the recent Zaedyus-1 well oil discovery in French Guiana and the recent oil discoveries in the offset conjugate margin area in Africa (Sierra Leone-Liberia), it is no surprise that explorers are looking to continue this success into the Foz do Amazonas Basin of Brazil. Foz do Amazonas is the most northerly of the Brazilian equatorial margin basins with an area of 282,909 km², and water depths ranging from 50 m to greater than 3000 m. In this under-explored frontier basin, exploration drilling has been confined to the shelf, with 95 exploration wells drilled and ten of these with hydrocarbon shows. The 11th Exploration Licence Round focused on the potentially large reservoirs in distal Late Cretaceous/Palaeogene deep-water turbidite plays, following successful wells drilled in French Guiana. There are strong indicators for the presence of hydrocarbon-bearing reservoirs shown in recent publications, based on newly available data (Rodriguez et al., 2014). This study complements some of the evidence previously presented by analysing the prospectivity within the Foz do Amazonas Basin. We use temperature gradients obtained from exploration wells and Ocean Drilling Programme (ODP) wells, as well as values calculated from the Bottom Simulating Reflector (BSR) to model the geothermal gradient and present-day source rock maturity.