f Production from Natural Fracture System in the Gibraltar Field – Colombia

The Eastern Cordillera foothill is characterized by high structural complexity rarely evident in 2D seismic profiles due to the deformation itself. The Gibraltar Field in the Sirirí block is located in one of the imbricate thrust sheets in a triangle zone. In this area three wells have been drilled so far, which had test gas and condensate productivity from a double porosity system in Mirador Formation. For better understanding of the variables controlling production into the structure, a static model was built integrating properties of the reservoir rock matrix and those from secondary porosity associated to fractures induced during folding. This study integrated well image logs into a static model. Spatial representation of each fracture plane using a Distcret Fracture Network (DFN) allowed calculates inherent properties to each fracture plane and those representing the relationship between them. Although the current stress orientation in the Northern Andes (from Seismicity Analysis) show a general ENE – WSW compression, data in the three wells suggest the presence of local stress perturbation, probably associated to a strike-slip component. This is mainly observed at the northern tip of the structure, where fluid flow could be enhanced in N-S direction.