Bruno De Toni¹, Juan Di Croce², Felipe Audemard³

(1) PDVSA EP, Caracas, Venezuela
(2) PDVSA E&P, Caracas, Venezuela
(3) PDVSA Exploración y Producción, Caracas, Venezuela

ABSTRACT: The Falcon Basin: A North Vergent Neogene Folded Belt

The onshore and offshore seismic data from Falcón and the surface geologic information have allowed to reinterpret this region as an assymmetric north vergent Neogene folded belt. The active deformation front is presently evolving along its northern flank where an overlapping system of ramped anticlines is accomodated within a regional triangle zone. The frontal monocline is partially overlain by an extensional system which in turn represent a collapse structure dipping to the north-northeast towards the flexural basin or Bonaire depression. Compressive deformation initiated in the early Miocene with the progressive northward emplacement of the triangle zone which is stratigraphically controlled by the thick shaly package of the Oligo-Miocene strata. The structural relief of this megastructure on top of the Oligocene sequence is at least 8 Km, from which 5 Km. are bellow sea level. The gravitational collapse opposes the regional backthrust and reach an extension of approximately 5 Km. at the tip of the triangle zone where it becomes in a toe thrust. The sole of the listric normal faults is virtually coupled to the roof-thrust of the Falcon allochthon, delaminated within the same thick shaly Oligo-Miocene unit of the Pecaya-Agua Clara formations. This suite of evidences modifies the current view of this area where the evolution of Falcon was fundamentally related to strike slip tectonics. The structural model proposed introduces new exploratory concepts wich are highly attractive in the search for light gravity oils and gas.

AAPG Search and Discovery Article #90906©2001 AAPG Annual Convention, Denver, Colorado