Brazil's Subsalt Estimates Revised

Brazil's offshore subsalt fields may hold enough undiscovered oil and gas to supply the world's current oil needs for over five years.

A new reserve estimate was presented at a conference in Rio de Janeiro by Professor Cleveland Jones and Dr Hernane Chaves of the National Institute of Oil and Gas at Rio de Janeiro State University. 

The new estimate of at least 176 billion barrels of oil equivalent (boe) of undiscovered, recoverable resources of oil and natural gas is more than four times the 30 billion to 40 billion boe already discovered in the region.

The estimates supersede earlier ones published by the researchers and are around 50 percent higher.

“Naturally this is a dynamic process, and with more information our estimates can change, although we see that there is a solid foundation for the range mentioned,” says Jones. “We are not likely to see major deviations beyond the extremes of our estimates, above or below, and more likely will see a narrowing of those extremes, as more information is obtained on new discoveries and recent assessments of prior discoveries, as well as about the few dry or uneconomical findings.”

This region has attracted attention since the first major discoveries were confirmed by Petrobras, in 2006. Since then, discoveries in the region have ranked among the largest in the world in the last ten years, including Lula (formerly Tupi), Iara, Libra and others.

The discoveries have led to various estimates, from the Brazilian government and Petrobras, including figures ranging from 50 to over 300 billion barrels of recoverable oil in the Picanha Azul region. As none of the estimates were accompanied by supporting technical data, the researchers commenced their analysis in 2010.