Additional Oil Identified With Moqueta-6 Delineation WellCALGARY, Oct. 12, 2011 /PRNewswire/ - Gran Tierra Energy Inc. ("Gran Tierra Energy") (NYSE Amex: GTE, TSX: GTE), a company focused on oil exploration and production in South America, today announced that it has initiated exploration drilling operations on two oil prospects in Brazil and exploration drilling operations on one oil prospect in Colombia. Delineation and development drilling is ongoing in Colombia, with additional oil column identified in the Moqueta-6 delineation well. "Two years after announcing a strategic decision to enter Brazil, Gran Tierra Energy has assembled a large land position and a diverse exploration and development drilling portfolio, with exploration drilling operations now initiated on two prospects, one onshore and one offshore. In parallel, our delineation and development drilling operations on recently discovered reserves in Colombia are ongoing, with exciting new delineation results indicating additional oil column in the Moqueta oil discovery. We have also begun additional exploration drilling on our lands in the Putumayo Basin of Colombia," said Dana Coffield, President and Chief Executive Officer of Gran Tierra Energy. BrazilBM-CAL-10 Block (Statoil 45% WI & Operator, Petrobras 40% WI, Gran Tierra Energy 15% WI) Statoil do Brasil Ltda. ("Statoil") commenced drilling operations on October 1, 2011 on the 1-STAT-7-BAS exploration well. The well is located in the deepwater portion of the Camamu Basin at a water depth of 6,200 feet, directly offshore from Salvador and the onshore Recôncavo Basin where Gran Tierra Energy's operated acreage is located, and is expected to take 60 days to drill. Documents associated with Gran Tierra Energy's two farm-in agreements with Statoil, whereby Gran Tierra Energy will be entitled to earn a 10% working interest in Concession Contract BM-CAL-7 operated by PetróleoBrasileiro S.A. ("Petrobras"), and a 15% working interest in Concession Contract BM-CAL-10 operated by Statoil, in the offshore Camamu Basin, are being prepared for submission to the Agência Nacional de Petróleo, Gás Natural e Biocombustíveis ("ANP") for regulatory approval.