Gran Tierra Preparing to Test Putumayo Basin Well

Gran Tierra Energy Inc. has successfully drilled and logged a new field wildcat well in the Guayuyaco Block, Putumayo Basin, in southern Colombia. Gran Tierra Energy holds a 50% working interest and is Operator of this block. Partner, Solana Resources Limited, holds a 50% working interest and Ecopetrol has a 30% interest back-in right on commercial discoveries. If Ecopetrol exercises its back-in right, then Gran Tierra Energy will hold a 35% working interest and retain Operatorship, and Solana Resources Limited will hold a 35% working interest in the new commercial field.

Gran Tierra reported that its Juanambu-1 well reached a total measured depth of 9,154 feet on March 10, 2007. The well encountered reservoir quality sandstones with hydrocarbon shows in four zones. Initial log interpretations indicate potential oil pay in the T Sandstone Unit of the Villeta Formation and in the Caballos Formation. There is additional potential oil pay in the Kg Sand Unit of the Rumiyaco Formation and in the U Sandstone Unit of the Villeta Formation, subject to confirmation by planned well testing. The four reservoirs encountered are proven producing reservoirs in oil fields in the adjacent Santana Block operated by Gran Tierra. The Juanambu-1 well bore is currently being cased. A service rig with test equipment will move to the Juanambu-1 location to run a completion string and initiate testing of the hydrocarbon zones in early April.

The Pride-17 drilling rig will be mobilized to the adjoining Chaza Block to drill the Costayaco-1 exploration well once the Juanambu-1 well bore is cased. Gran Tierra currently expects drilling of Costayaco-1 to commence in early April. Gran Tierra is the operator of the Chaza block with a 50% working interest.

Dana Coffield, President and Chief Executive Officer of Gran Tierra, stated, "These early positive evaluation results justify an extensive testing program to evaluate the commercial potential of the encountered hydrocarbons zones. The results of this testing activity will be particularly interesting to us as the Juanambu structure is in close proximity to adjacent land and infrastructure operated by Gran Tierra Energy."

Gran Tierra Energy, Inc. is an international oil and gas exploration and production company, headquartered in Calgary, Canada, incorporated and traded in the United States and operating in South America. The Company holds interests in producing and prospective properties in Argentina, Colombia and Peru.