Subsurface characterization of structural traps in the Outer Nunchia Foothills, Colombia

Abstract

The integration and interpretation of 2D and 3D seismic data, well information, geological maps and public information was used to identify the structural configuration of the outer Nunchia Foothills, to define the structural style and to evaluate the hydrocarbon prospectivity in terms of the structural configuration. A stack of hinterland-dipping monocline to imbricate structures were recognized. Based on the lower detachment levels, the outer Nunchia foothills were divided into three sub-divisions. The basal structures, with detachment in Gacheta Formation and involves Cretaceous rocks to León Formation. The Intermediate structures, with detachment level in Lower to Middle Carbonera, which involves rocks of Carbonera and León Formations; and the upper to surface structures, where the lower detachment is located in the Upper Carbonera and involves the younger rocks. In the outer Nunchia foothills, the reservoir units are involved only in the basal structures, where the southern structure was tested by the Tangara-1 well. The area is therefore classified to be of low hydrocarbon potential in terms of structural traps.