USS Milwaukee (CL-5) While steaming north of Hispaniola and Puerto Rico on 14 February 1939, "Milwaukee" discovered the deepest place in the Atlantic Ocean. The spot—which has a depth of —is now known as the "Milwaukee Deep". By January 1941, the ship had returned to Cruiser Division 2 which was now assigned to the Caribbean Patrol, commanded by Rear Admiral Jonas H. Ingram, part of the Neutrality Patrol established after the war began. Cruiser Division 2 was ordered to patrol the Atlantic between Trinidad, the Cape Verde Islands and the eastern bulge of Brazil in April, although "Milwaukee" was not immediately available. The
Sirena Deep Sirena Deep The Sirena Deep was discovered in 1997 by a team of scientists from Hawaii. Its depth (10,732 metres) is thought to be second or third only to the Challenger Deep and possibly Horizon Deep, currently the deepest known places in the ocean. It lies along the Mariana Trench, 200 kilometers to the east of the Challenger Deep and 145 km south of Guam. The Sirena Deep was most probably formed, not through transform fault motion as previously thought, but through a north-south convergence of the Caroline plate and the Pacific plate, in which the Caroline plate is subducting.