Brazilian Pre-Salt Province: History of Success and a Promising Future

Abstract

Since the 80's, Petrobras has spent continuous exploratory efforts in Santos Basin. In early 2000, Petrobras and partners commenced what became a major exploration campaign to have a better understanding of the hydrocarbon system of a previously studied but unexplored portion of Santos Basin. Santos External High is characterized by a unique geological setting on the Brazilian Continental Margin: a thick evaporitic layer up to 2,000 m thickness, overlying a syn-rift section up to 5,000 m thick. This area is characterized by a huge structural high trending NE/SW preferential for carbonate reservoirs deposition relatively to deepest surrounding areas.

After Brazilian Petroleum Agency Bid 2 round (2000), Petrobras and partners acquired four exploratory blocks in the ultra-deep water of Santos Basin. In 2001, a huge 3D seismic survey (20,000 km²) and ensuing seismic interpretation led to discoveries of the Pre-Salt play.

In 2006, Lula Oil Field, the first economic oil accumulation in the Pre-Salt of Santos Basin was discovered. This was the first Brazilian offshore supergiant accumulation with total recoverable reserves of 8.3 Billion boe. The first oil was produced through EWT three years later. Declaration of Commerciality occurred in late 2010. Current production is 853,000 bopd from 6 FPSOs. Lula Field is one of the biggest oil discoveries in the world in the past ten years.

This first exploratory success followed an intense drilling and evaluation exploratory campaign focused in other encouraging Pre-Salt prospects. This led to discovery of several other giant oil fields such as Sapinhoa (recoverable reserves of 2.1 Billion boe and currently producing of 325,000 bopd from two FPSOs), Lapa (recoverable reserves of 459 Million boe and production of 67,000 bopd), and Berbigão-Sururu-Atapu fields (total recoverable reserves in the range of 0.9 to 5.0 Billion boe). Additionally, there were other huge Pre-salt hydrocarbon accumulations discovered during this exploratory phase as Jupiter and Sagitario.

The discovery of the Pre-Salt hydrocarbon play exemplifies the successful E&P strategy conducted by Petrobras and its partners. Significant efforts reduced exploratory risks and uncertainties. As a result, 11 years after discovering the first Pre-Salt oil accumulation, about 50% of Brazil’s current production comes from the Cretaceous Pre-salt lacustrine carbonate reservoirs.

AAPG Datapages/Search and Discovery Article #90323 ©2018 AAPG Annual Convention and Exhibition, Salt Lake City, Utah, May 20-23, 2018