The "Fendouzhe", or "Striver", descended more than 10,000 metres into the Marianna Trench in the western Pacific Ocean with three researchers on board
The dive to Mariana was only the third time people have reached the ocean's extreme depths.
The findings showed that loss of sea water is due to the slow-motion collisions of tectonic plates under deepest ocean trench in the world.
Chinese scientists embarked on a deep-sea mission in the resource-rich South China Sea on Tuesday notwithstanding a simmering maritime dispute with many countries in the region.
The frequency of the moans were known to go as low as 38 hertz that tended to end with a metallic sweep finale that went up to 8,000 hertz
Titanic film director James Cameron has completed the world's first solo dive to the deepest known point on Earth, reaching the bottom of the Pacific Ocean's Mariana Trench southwest of Guam in a specially designed submarine.