Fault structure and earthquake potential, Southwest Puerto Rico

This project combines high-resolution seismic profiling, remote sensing image analysis, and field mapping to provide a three-dimensional geologic framework for the crustal structure of southwest Puerto Rico leading to a better understanding of active seismicity in the region. This project is supported by the U.S.G.S. National Earthquake Hazard Reduction Program (NEHRP).

The island of Puerto Rico is part of a microplate caught within the a broad boundary zone between the Caribbean and North American plates. Relative motion between these plates is predominantly left-lateral strike-slip. There is a poorly resolved and slightly ambiguous oblique component of motion causing apparent transpressional and transtensional structures within the boundary zone. An active seismic network on the island indicates a fairly high level of seismicity yet detailed fault structure on the island is not well known.

In December 1994-January 1995 we collected two high-resolution seismic profiles across the southern boundary of the Lajas Valley

Additional coincident geophysical data collected include:

Collaborators:
Hans Schellekens: University of Puerto Rico, Mayaguez
Charles Almy: Guilford College