NANJING - An oceanographic ship carrying China's manned deep-sea submersible left eastern port city of Jiangyin Sunday for the Mariana Trench to attempt the world's deepest manned submersible dive.

The Jiaolong submersible, named after a mythical sea dragon, will go 7,000 meters under the surface of the Pacific Ocean between mid-June and early July, according to the voyage's plan.

The Jiaolong is the world's first manned submersible designed to reach depths of 7,000 meters below sea level.

The submersible succeeded in diving 5,188 meters below sea level in the Pacific Ocean last summer, enabling China to conduct scientific surveys in 70 percent of the world's seabed areas.