Structural Analysis of the Neiva Fold-and-Thrust Belt, Upper Magdalena Basin, Colombia: New Opportunities for Petroleum Exploration in a Mature World-Class Hydrocarbon Province

Freddy Corredor¹, Fernando Munar², and Claudia Rosa Posada^2
1 Harvard University, Cambridge, MA
² Ecopetrol S. A, Bogotá D. C, Colombia

The Neiva sub-basin, Upper Magdalena Basin, Colombia is a mature petroleum province located between the Central and Eastern Cordilleras in the northern Andes. A new detailed kinematic analysis based on the quantitative structural interpretation of a large high quality 3D seismic survey across the northern portion of the Neiva sub-basin reveals the complexities of the east verging fold-and-thrust belt that form this region, as well as multiple new opportunities for petroleum exploration across this basin. The Neiva sub-basin offers an extraordinary opportunity to study fold-and-thrust belts in active margins, as the structures are extremely well imaged at deep levels in a 3D seismic reflection volume and because they preserve growth strata that record fold kinematics. Using the patterns of growth sedimentation, fold shapes, fault plane seismic reflections, and fault-related folding theories, we describe and model the structural styles and kinematics of the fault-related folds that compose this fold-and-thrust belt. Through the sequential restoration of two regional depth converted seismic sections across this thrust system, we resolve the structural styles, the timing and sequences of thrusting, as well as the regional amounts of shortening, all of which have important implications for hydrocarbon maturation and charge in the Upper Magdalena Basin. Based on the patterns of growth sedimentation, a model of continuous shortening and imbrication across the Neiva sub-basin through out the Tertiary is preferred over the generally accepted models of episodic deformation.

AAPG Search and Discovery Article #90039©2005 AAPG Calgary, Alberta, June 16-19, 2005