The First Results of the 5-Year Exploration Plan in the Brazilian New Frontiers Basins
On August 2008 the current Brazilian Petroleum Law completed ten years of its existence. This tenth-year anniversary was a very special moment to inspire some thoughts on the scenario established by this law. In this period, what have we experienced and what have we improved so far?
PETROBRAS, the Brazilian state-owned company, has improved its performance and has added new important reserves to the established ones. Some major international companies are achieving success in the main Brazilian offshore basins, but there are six onshore sedimentary basins (180,000 sq km) completely unknown and about 15 sedimentary basins (4,800,000 sq km) fairly known, an area where planned researches could provide good results some years in the future. Facing this situation, the Brazilian Petroleum Agency (ANP) approved in 2007 a geological and geophysical program focused on new frontiers basins. This program is a 5-year plan designed in order to discover the real potential of such large areas and it is based on data acquisition. The exploration process starts with gravimetry and magnetometry surveys, followed by geochemistry surveys, regional 2D seismic surveys, stratigraphic well drilling and integrated evaluation of oil & gas potential. In Brazilian territory, there are large Paleozoic basins poorly known and together have an area of 2,407,403 sq km (47% of the total basins’ areas included into the plan).
The firsts results started to appear. Geochemistry surveys covered 484.832 sq km. Geophysical aerial surveys covered 1.358.096 sq km. In 2008 the first wide regional seismic survey started, with 1,600 km. These data have been analyzed with good results.
Anomalies detected in the geochemistry surveys have pointed out the possibility of good areas to increase the researches or even revealing areas ready to be offered in the Brazilian Bidding Round for Exploratory Blocks. An important anomaly discovered by geochemistry survey in Parecis Paleozoic basin allowed the inclusion of 14,026 sq km of area in the last round.
Anomalies detected in the geophysical aerial surveys have indicated the best areas in which more detailed researches should be focused. Some anomalies pointed out by a gravimetric and magnetometric aerial survey were related to gas seeps in São Francisco Basin.
This plan represents a huge governmental effort to get to know the real oil & gas potential of Brazilian onshore basins, and this effort has already started to bear its fruits.
AAPG Search and Discovery Article #90090©2009 AAPG Annual Convention and Exhibition, Denver, Colorado, June 7-10, 2009