The Puerto Rico Graben is a geological feature located in the northeastern Caribbean, specifically in the region of Puerto Rico. It is characterized by a series of faults that create a block of the Earth's crust that has dropped between two other blocks. This structure is significant for understanding the tectonic activity in the area, as it is influenced by the interactions between the North American Plate and the Caribbean Plate. The graben is part of a larger tectonic setting that includes the Puerto Rico Trench, which is the deepest part of the Atlantic Ocean. The geological processes in the Puerto Rico Graben contribute to the region's seismic activity, making it an area of interest for scientists studying earthquakes and plate tectonics.