The Fantastic Microbialite Reservoirs in Santos and Campos Basins: Depositional Models, Crustal Inheritance Control on the Petroleum System and Risks Associated for Commercial Discoveries
Event name: First EAGE Workshop on Pre-Salt Reservoir: from Exploration to Production
Session: Session IA
Publication date: 06 December 2019
Info: Extended abstract, PDF ( 391.33Kb )
Price: € 20
The Pre-Salt of the Santos and Campos Basins in Southeastern Brazil is a remarkable, world-class petroleum province. The secrets to such astounding success and profitability are three: (1) a surprising reservoir, the microbialites, (2) a perfect geometrical conjuction of a central focusing structural high flanked by two hydrocarbon kitchens containing world-class lacustrine source rocks; and (3) a perfect seal; thousands of meters of evaporites spread continuously throughout the deep and ultra-deep waters of the basins. Three major hypothesis prevail nowadays regarding the origin of the microbialite reservoirs and their impressive permo-porosity properties. A purely biogenic model (carbonate ramp), a purely abiogenic model (evaporitic deposition) and a mixed model (travertine hydrothermal buildups). The major elements of the petroleum system are inherited from the underlying Precambrian crustal structure: the hydrocarbon kitchens, the focusing high and migration routes. No comprehensive risk analysis can be performed without the full understanding of this crustal framework.