The Caguán-Putumayo Basin, is located in the southwest of Colombia and covers an area of 110 304 km2 (Caguán at north and Putumayo at south, Figure 1). It limits to the west with the Eastern Cordillera and to the east with the Guyana shield; to the north with La Macarena Range and to the south with Ecuador’s international boundary. This basin shares its geological history with the Oriente Basin in Ecuador, as a part of a foreland type basin. Although the north zone of the basin has been less explored the oil seeps and the drilled wells containing hydrocarbons, show at least one active petroleum system. The traps present in the two zones are broadly classified as thrust systems, high angle strike-slip faults with associated folds and blind faults in the foothills; and as normal faults and onlapping in the foreland zone. The seal rocks of the system have been identified in shaly intervals of the Caballos, Villeta/ Macarena, Rumiyaco, Orteguaza, Arrayán and Serranía formations.