China begins deep-sea research in northwestern Pacific Ocean

China's manned submersible Jiaolong departed from south China's Shenzhen for deep-sea dives in northwestern Pacific Ocean Tuesday.

The ship Xiangyanghong 09 set sail for the Yap and Mariana trenches, with Jiaolong and 96 scientists aboard, marking the beginning of the third stage of China's 38th oceanic expedition.

During the mission, which runs until June 18, the submersible is expected to conduct nine deep dives in the two trenches.

"Ocean trenches are the deepest parts of the sea floor," said Wu Changbin, general commander of the third stage of the expedition. "The Yap Trench has a depth of 8,527 meters, and Mariana Trench, the deepest known point in the Earth's oceans, has a depth of 11,034 meters."

The scientists plan to conduct five dives in the Yap Trench to study deep-sea biotic communities and gene resources.

In addition, Jiaolong will conduct manned deep dives in the Mariana Trench to investigate the deep-sea environment.

The 38th oceanic scientific expedition started on Feb. 6. Jiaolong completed a dive in the northwestern Indian Ocean earlier this year during the mission's first stage.

Jiaolong will be examined and upgraded after the mission, and a new mother ship is expected to be put into use in 2019, according to Wu. Endit