Prospect Evaluation Methodology Of Structure Trap In Subandean Basin, Bolivia

In the present work, a previously defined prospect in the Bolivian south sub-Andean basin is re-evaluated. A preliminary interpretation based only on seismic data defined an apparently interesting prospect. A posterior revision of the area, applying a different methodology, based on a interactive combination of seismic and structural data, obtained a different interpretation. The applied methodology basically consists on the interpretation of the unambiguous data in the seismic, conversion to depth and matching to the surface structural data. Structural criteria were used for reconstruction the parts where seismic is ambiguous or with no data. After the reconstructed cross-section is balanced, a ray tracing analysis is applied to check whether the interpretation is consistent or not with the strike seismic line on the backlimb of the structure. The process is repeated on all the 2D time seismic lines obtaining 2D structure balanced depth sections. With these 2D structure sections, a 3D structural model is built and restored using 3DMove software. The resulting structure map of the prospect is deeper than previous interpretation. An implication of reconstructing the whole area, not only mapping the crest of the traps but also syncline area, made possible to model the hydrocarbon generation of the fetch area. The result of 1D Basin modeling indicated that the source rock in the fetch area only have small amount of hydrocarbon generation. The analysis shows that this prospect have more economic risk than previously thought.