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Jose Castrillo, Universidad de los Andes (Venezuela)
Francisco Bongiorno, Universidad de los Andes (Venezuela)
Leonardo Gonzalez, Universidad de los Andes (Venezuela)
Oscar Odreman, Universidad de los Andes (Venezuela)
Fernando Mazuera, Universidad de los Andes (Venezuela)
Julian Gutierrez , Universidad de los Andes (Venezuela)
Maria Elberg, Universidad de los Andes (Venezuela)
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In the central part of the Merida Andes the structural style is characterized by the development of positive flower structures associates with the Bocono fault system. The field study shows an overturned stratigraphic secuences, high angle SE verging reverse faults, drag folds, narrow asymmetric anticlines and syncline, with an NE-SW orientation in some cases with subvertical axial axes. These structures form a complex mosaic of folds and thrust where the most important feature is represented by the Mesa Bolívar-Jají-La Hechicera thrust, plurikilometric, tectonic sheet slice, along the study area from SW to NE, this feature shows a tectonic displacement verging NW involving the basement and sedimentary cover in the deformation. At the SW of the study area, the igneous-metamorphic basement overthrust the cretaceous and tertiary secuences. This stratigraphic series appear overturned facing the main thrust. In the NE, the thrust is identified by jurasic rocks overthrusting on the younger stratigraphic series. The analysis carried out, integrating radar imagery, cross sections and field data allow us to propose a model for the Merida Central Andes in the study area comparable to flower structure system associated with the Bocono strike- slip fault. These structures has been developed as resulted of the reactivation of the right lateral strike-slip of the Bocono fault starting in Miocene, caused by the compressive regime in response to the main stresses oriented SE-NW. This interpretation is compatible with the Andean geodynamic at the regional scale where the NW-SE orientation of the Merida Andes is obliquely within the stress field of the Late Cenozoic resulting in a strain partitioning divided in strike-slip faulting parallel to the chain and thrust folds, associated due to transpression related to oblique convergence between two independents blocks belonging to the Southamerican plate: The Maracaibo block in the north and the Guyane Shield in the south.
Keys Words: Strike-slip, flowers structures, Boconó fault, Cenozoic, Mérida Central Andes.
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