--> Structure and Hydrocarbon Prospectivity in the North Panama Deformed Belt: Observations From Latest Seismic Reflection Imaging

AAPG ACE 2018

Datapages, Inc.Print this page

Structure and Hydrocarbon Prospectivity in the North Panama Deformed Belt: Observations From Latest Seismic Reflection Imaging

Abstract

Newly-acquired 2D seismic reflection data provides unprecedented insights into the structure and potential petroleum system(s) of the North Panama Deformed Belt (NPDB) and its vicinity. The NPDB is an arcuate accretionary wedge situated north of the Panamanian isthmus in the Caribbean Sea, flanked by the San Blas basin to the south, and the underthrusting Colombian Basin to the north. The complex faulting within the accretionary wedge shows changes in vergence influenced by slope gradients, mechanical variations in the detachment horizon, and regional stresses. Sediments in the trench basinward of the wedge show onlap onto Colombian Basin strata, consistent with foreland flexure and obduction (backthrusting) of Panama onto the Colombian Basin.

Preliminary data processing suggests that seismically-bright Maastrichtian shales could be present at the base of the prism within a duplex thrust system. This duplex feature improves prospectivity relative to a single decollement surface, which can act as a barrier to hydrocarbon migration. We discuss the options for possible source rocks, taking into account hydrocarbon occurrences in the Atrato-Uraba area and the Sinú-San Jacinto basin. Intra-prism reservoir intervals are dependent upon models for Magdalena/Atrato River dispersal systems prior to accretion. Prism thickness above the Cretaceous can reach up to 8km increasing opportunities for thermal maturation. Amplitude anomalies are observed in fault-bound sections within the prism indicating the potential for localized hydrocarbon accumulations. Seismic lines on the western side of the NPDB suggest that the San Blas basin may extend farther to the west than previously thought increasing the potential area for hydrocarbon accumulation.