Published 1995 as part of Memoir 62
Copyright © 1995 The American Association of Petroleum Geologists.   All Rights Reserved.

The complex Caribbean-South American plate boundary records a Late Cretaceous-Eocene phase of terrane collision followed by Eocene-Recent right-lateral displacement. This study analyses the stratigraphy deposited during the latter stage in a series of episutural pull-apart basins. On the basis of regional seismic, well control, field work, and published information, this succession is divided into four unconformity-bounded depositional sequences. These cycles are upper Eocene-lower Oligocene, upper Oligocene-lower Miocene, middle-upper Miocene, and Pliocene-Recent. The remnants of upper Eocene and lower Oligocene rocks are mostly restricted to narrow, fault-controlled northwest-southeast depocenters. During the late Oligocene-late Miocene, sedimentation was still fault controlled but more widespread. Sedimentation rates along these growth faults were extremely high (up to 350 m/m.y.), but generally decreased through time.

During the Eocene, the axis of maximum subsidence was located in the western part of the Golfo de Venezuela, at the contact between autochthonous and allochthonous units emplaced during a prior collisional event. During the Oligocene and Miocene, the axis of maximum subsidence was located farther east, in the Urumaco trough and east of La Vela Bay. At the same time, an ENE-WSW oriented depocenter began to develop in the Falcón basin in response to loading by a northward-advancing thrust front. Finally, during the Pliocene, the largest subsidence rates occurred south of the Golfo Triste, in a pull-apart area created by the right-lateral displacement of the Boconó and Oca faults.