ABOARD XIANGYANGHONG 09, June 29 -- Jiaolong, China's first manned deep-sea submersible, finished positioning tests on Sunday during its first preparatory phase prior to a scientific expedition in the Pacific Ocean.

Both home-made and imported ultra short baseline locating systems, which serve for real-time positioning of Jiaolong by its carrier, were tested and they were stable, said researchers on the submersible.

Its carrier, Xiangyanghong 09, set sail from a port in the city of Jiangyin in east China's Jiangsu Province and arrived at the operation seawaters in the South China Sea in the early hours of Saturday.

Jiaolong is scheduled for a July voyage in the west Pacific Ocean, during which it will research cobalt-rich crusts in the ocean and life forms inhabiting the bottom of the ocean.

In 2012, Jiaolong achieved a record dive depth of more than 7,000 meters in the Pacific's Mariana Trench.

Jiaolong is scheduled to arrive at Mawei Port in east China's Fujian Province on Tuesday, and will later sail to the west Pacific for scientific research.