“…Petrographic studies are of key importance for characterizing the types, timing and rate of the main diagenetic processes affecting sandstone porosity and permeability (Ajdukiewicz and Lander, 2010). Presently, the Equatorial Margin basins attract a great interest for hydrocarbon exploration in Brazil (Favera et al, 2013;Mello et al, 2013). In 2013, Brazil's National Agency of Petroleum, Natural Gas and Biofuel (ANP), conducted the eleventh bidding round that offered 289 blocks in eleven different basins, with a heavy focus on the Equatorial Margin (www.anp.gov.br).…”