GRIBOULARD, ROGER, CLAUDE BOBIER, JEAN CLAUDE FAUGERES, and ELIANE GONTHIER, no affiation given

ABSTRACT: Relationship Between Tectonics, Argilokinetic Structures, and Environmental Patterns at the South Boundary of the Barbados Accretionary Prism

Recent studies have been carried out on limited sectors of the South Barbados accretionary prism. They are supported by SeaBeam maps analysis, high resolution seismic data, time-lapse and video camera tracks, numerous cores and Side Scan Sonar data.

The analysis of these data point out numerous evidences of an

active and present tectonic activity on the southern part of this domain.

The development of very large indurated sea-bottoms on which deep-sea communities frequently occur and where we can observe some "sigmoidal" features and network of conjugate fractures which suggest the presence of shear deformation zone. In addition, tracks of important and probably deep faults extend across both soft and indurated bottom sediments.

The regional morphological anomalies are comparable to analogical deformation model for a thick cover sticking out of its substratum and the tectonic activity is closely associated to the presence of deep dysharmonic levels which control, obviously, an important clay-diapirism. This is an effect of both the structural location of this region, at the junction of three lithospheric plates (Caribbean, Atlantic, and South-American) and paleogeographical and sedimentological changes since Neogene time, with the very important terrigeneous supplies coming from the Orinoco River.

Consequently, the main deformations that we observed in this region are rather under influence of shearing and transpressive than compressive movements.

AAPG Search and Discovery Article #90988©1993 AAPG/SVG International Congress and Exhibition, Caracas, Venezuela, March 14-17, 1993.