Location map Puerto Rico trench—United States Geological SurveyPerspective view of the sea floor of the Atlantic Ocean and the Caribbean Sea. The Lesser Antilles are on the lower left side of the view and Florida is on the upper right. The purple sea floor at the center of the view is the Puerto Rico trench, the deepest part of the Atlantic Ocean and the Caribbean Sea.
The trench is 800 kilometres (497 mi) long[1] and has a maximum depth of 8,376 metres (27,480 ft)[2] or 5.20 miles. This constitutes the single deepest point in the Atlantic Ocean. This point is commonly referred to as the Milwaukee Deep, with the Brownson Deep naming the seabed surrounding it.[3] However, more recently, the latter term has also been used interchangeably with the former to refer to this point.[4][5][6] The exact point was identified by the DSSV Pressure Drop using a state-of-the-art Kongsberg EM124 multibeam sonar in 2018, and then directly visited and its depth verified by the crewed submersible Deep-Submergence Vehicle DSV Limiting Factor (a Triton 36000/2 model submersible) piloted by Victor Vescovo.[7][8][9]
Scientific studies have concluded that an earthquake occurring along this fault zone could generate a significant tsunami.[10] The island of Puerto Rico, which lies immediately to the south of the fault zone and the trench, suffered a destructive tsunami soon after the 1918 San Fermín earthquake.
^NOAA Ocean Exploration. "Mission Plan". Oceano Profundom 2015: Exploring Puerto Rico’s Seamounts, Trenches, and Troughs. Retrieved January 28, 2023.
^"Atlantic Ocean". Five Deeps Expedition. Archived from the original on 2020-04-13. Retrieved 2020-01-24.