Deformation Due to Shale Tectonic in Northwestern Venezuela

Miguel Nunez, Amran Benguigui, Aisha Paez, Jorge Acosta, Jesus Rodriguez, Yamily Vergara, Erick Moreno, John Gonzalez, Marcos Romero, and Saileth Cortez. Exploración, PDVSA, Av. 5 de Julio. PDVSA Exploración y Producción, Maracaibo, 4001A, Venezuela, phone: +58 261 8068376, nunezmf@pdvsa.com

The Maracaibo basin in nortwestern Venezuela is the most profilic petroleum province in South America. High angle basement reactivated normal faults that generate listric faults in the cover were previously interpreted for the eastern part of the basin. Backstripping maturation and migation modelling hardly explained proved hydrocarbon ocurrence within this region using the structural control inserted by these basement faults.

Structues associated to shale tectonic such as turtles, weldings and isoleted subbasins are revealed by the new interpretation of the region. This tectonic setting implies the presence of a detachment level along which these structures were developed during the Cenozoic. At least two phases of deformation are interpreted for the region: lateral expulsion of shale due to differential loading and a later shale upwelling related to inversion episodes. The understanding of the evolution of these new structural elements allows to postulate new migation paths which are favourable for hydrocarbon trapping and accumulation along the region.

Improved Understanding of Plays Related to Salt and Shale Tectonics I
2005 AAPG International Conference and Exhibition (September 11-14, 2005) Technical Program