خندق ماريانا
In 1984, the Japanese survey vessel "Takuyō" (拓洋) collected data from the Mariana Trench using a narrow, multi-beam echo sounder; it reported a maximum depth of , also reported as ±. Remotely Operated Vehicle "KAIKO" reached the deepest area of the Mariana Trench and made the deepest diving record of on 24 March 1995.