Seismic Stratigraphy of Camamu Basin, Northeastern Brazil

Abstract

The Camamu Basin is located at the northeastern Brazilian coastline and has significant hydrocarbon potential in both shallow and deep water settings. However, despite an already operating productive gas field, the basin is not well known. Herein, a regional stratigraphic interpretation of the rift, the transitional and the drift megasequences is reported, based on a data set of 152 post-stacked 2D seismic lines, 1 3D seismic cube and 34 wells with eletro-logs. The study revealed that the rift megasequence is much more complex than previously thought. In the southern region of the Camamu Basin, five rift sequences were mapped, while in the northern region, in the area of the regional tectonic lineament known as the Salvador Transcurrent Zone (STZ), seven rift sequences were recognized. This difference suggests a tectonic control during the rifting process, because the northern region is intensely affected by shear stress induced by transcurrent tectonics of the STZ during the crustal breakup. For the post-rift or "transitional" phase associated with thermal subsidence installed after the rift, as well as for the drift succession, the tectonic control exerted by Salvador's Transcurrent Zone is not detectable and the tectono-sedimentary evolution of the basin follows the general pattern of the Brazilian marginal basins.