Sequential Development and Deformation of Florida-Bahamas Passive Margin in Cuba

R. Tenreyro-Perez, J. G. Lopez-Rivera, J. R. Carballo-Garcia

The North-American passive margin in Cuba was intensively folded and faulted by alpine orogeny to form a thick thrust suture. This suture extends 1000 kilometers from West to East along the Northern half of the island and offshore. This study is based on extensive seismic reflection data coverage augmented by deep wells, seismic refraction as well as gravimagnetic and surface geologic surveys. This data is then utilized to understand present day structure and infer geologic evolution.

Basin development commenced with syn-rift lower Jurassic sequence. Since the upper Jurassic until middle Cretaceous in the drift stage, the basin on the continental plume has subsided. The uplift commenced in the Cretaceous and ended in the middle Eocene. This tectonic episode can be related to oblique island arc-continent collision. Since the upper Eocene orogeny ceased, a new plate boundary developed to the South.

Carbonate sedimentation dominated during drift stage in two domains; basinal and platform. The deformation of the sedimentary wedge began in the basin and propagated towards the platform. Profiles reveal that the suture consists of a series of tectonic sheets of volcanic and continental margin rocks which also involves foreland basin sequences. Total thickness varies from 8 to 10 kilometers. The main decollement is considered in the bottom of upper Jurassic but in the basinal domain at least one more level is recognized in lower Cretaceous. The general model of the thrust belt considers a piggy-back sequence of faulting, in which an out of sequence flat thrust can be recognized.

AAPG Search and Discovery Article #91020©1995 AAPG Annual Convention, Houston, Texas, May 5-8, 1995