Gran Tierra Energy, Inc. provided updates for its exploration and operation activities in Colombia, Argentina, Peru and Brazil. Colombia: Chaza Block, Putumayo Basin, Colombia (Gran Tierra Energy 100% working interest and operator). Gran Tierra Energy completed initial testing of Moqueta-7 by collecting reservoir data and fluid samples with a hydraulic jet pump from the T-Sandstone and Caballos formations in three repeated fault blocks.

The T-Sandstone formation in the primary fault block consisted of 44 feet true vertical depth ("TVD") gross reservoir or 33 feet TVD of net reservoir thickness. It was perforated and tested from 6,641 feet to 6,710 feet measured depth ("MD") for 78 hours at a rate of 463 barrels of oil per day ("BOPD") of 23.7deg API oil with a 0.4% water cut. The underlying Caballos formation consisted of 200 feet TVD gross reservoir or 68 feet TVD net reservoir thickness.

It was perforated and tested from 6,890 feet to 7,183 feet MD for 59 hours at a rate of 267 BOPD of 23.8deg API oil with a 1.1% water cut. A repeated oil-bearing Caballos Sandstone reservoir section was encountered in a new, previously unrecognized, fault block with 90 feet TVD of gross reservoir or 55 feet TVD of net reservoir thickness. The interval from 7,466 feet to 7,528 feet MD was perforated and tested with a hydraulic jet pump for 5 hours at 100 BOPD of 25.3deg API oil with a stabilized water cut of approximately 1%.

As drilling continued, a second fault was crossed and another repeated oil-bearing Caballos Sandstone reservoir section was encountered in a new, previously unrecognized fault block. It had 139 feet TVD of gross reservoir or 60 feet TVD of net reservoir thickness. The interval from 7,680 feet to 7,790 feet MD was perforated and tested for 13 hours with a hydraulic jet pump at 316 BOPD of 26.5deg API oil with a 2.8% water cut.

Moqueta-7 bottom hole location is believed to be near the western extremity of the main block of the Moqueta field. The well, because of its bottom hole position, will be completed as a water injector for pressure maintenance to enhance oil recovery and production from producing wells in the main block. Initial drilling results have been obtained from the Moqueta-8 appraisal well, with a bottom-hole location 450 meters southeast of the Moqueta-5 producing well.

Oil shows encountered during drilling indicate the presence of oil-bearing reservoir sandstones in the Villeta U Sandstone beginning at 4,865 feet MD (4,283 feet TVD) with an approximate potential gross reservoir thickness of 40 feet MD (32 feet TVD). The Villeta T Sandstone with oil shows were encountered at 5,152 feet MD (4,515 feet TVD) with an approximate potential gross reservoir thickness of 106 feet MD (70 feet TVD). The underlying Caballos formation with oil shows was encountered at 5,350 feet MD (4,674 feet TVD) with approximately 260 feet MD (97 feet TVD) of potential gross thickness.Gran Tierra Energy is planning to conduct the initial testing for Moqueta-8 in January 2013.

Moqueta-9, the next well in the appraisal program to further define the reserve potential of the field, is expected to begin drilling in February 2013. Argentina: Puesto Morales Block, Neuquen Basin (100% working interest and operator). The PMN-1117 horizontal well reached a total depth of approximately 2,130 meters MD (1,408 meters TVD) on October 27, 2012.

The well was drilled with a 483 meter horizontal section and multi-stage fracture stimulation was conducted on the well with production testing initiated on December 2, 2012. During the first 24 hours, this well flow tested at a rate of approximately 840 BOPD from the tight oil Loma Montosa reservoir. This well is currently flowing naturally at a choke-restricted rate of 212 BOPD of 33.8deg API oil with a 0% water cut.

Peru: Block 95 (100% working interest and operator subject to PeruPetro S.A. and Peruvian Government approvals). Gran Tierra Energy began drilling the Breta a Norte 95-2-1XD exploration well in Block 95 on December 15, 2012. This well will continue drilling into the first quarter of 2013, with initial results expected at the end of the quarter.

The bottom-hole target is located approximately 3.7 kilometers south of the Breta a-1 well, which was drilled in 1974 and tested 18deg API gravity oil on natural flow rates of approximately 807 BOPD. Gran Tierra Energy Peru S.R.L. currently holds a 60% working interest in Block 95 and has entered into an agreement to purchase the remaining 40% working interest from Global Energy Development plc Subject to PeruPetro S.A. and Peruvian Government approvals, Gran Tierra Energy will have a 100% working interest in Block 95.