Regional Fault Striation Studies
in the Circum-Caribbean Region

Funding agency: National Science Foundation
Award number: 0340639
Start Date: February 1, 2004
Expires: January 31, 2007

Abstract
This three-year U.S.-France cooperative research project involves Paul Mann at the University of Texas at Austin and Jean-Claude Hippolyte at the Universite de Savoie in France. They will perform fault striation studies applied to problems of active tectonics of the Caribbean plate. Completed studies in Puerto Rico have identified fault scarps with earthquake potential in these densely populated coastal regions (cf. reference list). Current studies are focusing on the islands of Vieques (eastern Puerto Rico), St. Croix (U.S. Virgin Islands), and Trinidad and Tobago.

A unifying theme of the study is the fault kinematics of the tightly curved eastern Caribbean arc system and its tectonic similarities and differences with other tightly curved arcs including the western Alps, Carpathians, Alboran Sea, Banda Sea and Scotia Sea.

View of reverse fault affecting late Miocene marine sedimentary rocks exposed on east coast of Trinidad. J.C. Hippolyte for scale.

Their specific objectives include:

1. identifying late Cenozoic sedimentary units affected by faulting (offshore, active faults will be used to target likely areas where these faults might extend onshore).

2. finding manmade outcrops in rock quarries and along road cuts that expose striated fault planes.

3. measuring striated fault surfaces to determine the types and orientations of faults present.

4. examining faults in different aged stratigraphic units, establish a fault kinematic history for the opening of the Anegada Passage.

5. using marine data to better understand the offshore extensions of faults.

6. compiling database of all fault striation data in the circum-Caribbean region and compare to earthquake and GPS results.

View of normal fault affecting Plio-Pleistocene shoreface sandstone of Mayaro Formation exposed on southeast coast of Trinidad. J.C. Hippolyte for scale.

The U.S. investigator brings to the project expertise in quantitative plate reconstructions, land based geological studies and marine geophysical studies. This is complemented by French expertise on the tectonics of highly curved orogenic belts including the Alps, the Carpathians and the Caribbean. The project will advance understanding of seismicity in this densely populated Caribbean region. The project is jointly supported by the National Science Foundation (NSF) and the Centre National de la Recherche Scientifique (CNRS). NSF will support the expenses of the U.S. investigator and the CNRS covers expenses of the French investigator.