Cuenca Putumayo (Colombia)

The Putumayo Basin is located in south western Colombia (total area of 29,000 km) and continues into Ecuadorian Oriente Basin. 395 x 106 bo has been discovered and 305 x 10~ cfg, with 105 exploratory wells drilled since 1948. Typically, reservoir levels are sandstones of the Caballos Fm (Aptian-Albian) and also the “U” and “M2” sandstones of the Villeta Fm (Late Albian Santonian). The Caballos Fm is the most important reservoir in the western area of the basin showing 12 to 15 % of porosity and up to 500 mD of permeability. Compaction by overburden can be associated to the beginning of HO maturation and migration and contemporaneous subtle structures, determining potential traps. Two main tectosedimentary systems progressively superimposed along time (from Upper Cretaceous to Recent) as well as in space (from West to East) are recognized: a) Early due to vertical compaction by lithological overburden from deposition onwards and b) Late due to the subhorizontal shortening related to the development<br>of the Post-Eocene Andean transpressional deformation. In addition to the traditionally well known Cretaceous-Paleocene petroleum system, there are others potential sources (Paleozoic and/or Mesozoic) of hydrocarbons that are probable to be found into the Putumayo Basin.