Figure 2. Map of the study area, showing the bathymetry, contours every kilometer, the extent of the carbonate platform in the different areas, the major geological features, and the locations of our data sources. Data source locations include the track lines of the surveys, the locations of the wells, and the locations of the earthquake profiles. Bathymetry is an integration of EW 96-05 Hydrosweep, ETOPO-5 digital terrain map, and National Ocean Survey hydrographic data sets [Mercado, 1994]. Solid lines are track lines of different surveys. North America-Caribbean plate motion vector according to DeMets et al. [1996]. The light gray area shows the extent of the carbonate platform as observed in seismic reflection profiles and side scan images. The rifts are shown is a darker gray, bounded by normal faults and the darkest gray areas are the islands. PRT, Puerto Rico trench; SPRSFZ, South Puerto Rico Slope fault zone; NPRSFZ, North Puerto Rico Slope fault zone; GNFZ, Great Northern fault zone; GSFZ, Great Southern fault zone.