Exploring for Unconventional Resources in the Turbidite Sands of the Recôncavo Basin, Onshore Brazil

The Candeias Formation is the early deepwater rift fill phase in the Reconcavo Basin, which reaches over 1200 m thickness in the deepest parts of the basin (Bruhn, 1999). In addition to the important early rift source rock member at the base of the Candeais Formation, there is also relatively low TOC kerogen distributed throughout the Candeais Formation shale. . In the grabens of the rift there is a lacustrine turbidite facies present which forms the Gomo Member. Where the sands of the Gomo Member are present they form a tight sand reservoir encased in the thick Candeias Formation shale. The elements of this unconventional play concept have been confirmed by analysis of the first two wells drilled by Alvopetro Energy in the Miranga Low of the Reconcavo Bain. Most of the producing fields in the basin are controlled by structural horst block traps hosted in Agua Grande and Sergi Formation reservoirs. The Candeais Formation in the Miranga Low graben structure, originally thought to be in the oil window, is found to have reached gas maturity.