Petroleum geology and exploration potential of Oriente-Maranon Basin

Oriente-Maranon Basin is one of the Sub-Andean foreland basins developed and formed on the basis of Margin of Craton. Oriente-Maranon Basin went through three evolution phases: marginal basin of craton, rift basin and foreland basin. The phase of rift basin formed the primary source rocks and reservoir and seal. Triassic-Jurassic Pucara Group and Cretaceous Chonta Formation generated a mass of hydrocarbons in Paleocene-Eocene (60–45 Ma) and Miocene (15–5 Ma), respectively. There are several reservoir-seal assemblages developed in the foreland basin. The assemblage of self-generating and self-preserving reservoir was the most important type in Cretaceous Chonta Formation. There are basement-involved thrust traps and detached thrust faulted/folded traps in western basin, drape and extruding anticline traps in central basin, and traction anticline traps in eastern basin. The different types of traps are distributed along the NW-SE direction. Four potential exploration targets are: Drape and extruding anticline traps in the source rock drainage area in Chonta Formation in central-western basin; Traction and extruding anticline traps in the source rock drainage area in Pucara Group in central-southern basin; Pucara Group Carbonate traps in central basin; Lithologic traps in upper Cretaceous and lithology-stratigraphy traps in upper Paleozoic in the northern and eastern exploratory area.