The Chinese scientific research vessel Tansuo-1 arrived in Guangzhou, Guangdong province, on Sunday after completing the first China-Chile joint manned deep-sea expedition to the depths of the Atacama Trench off the coast of Chile, demonstrating major progress in international marine scientific cooperation and China's active participation in global ocean governance.

The Atacama Trench is the world's longest ocean trench, reaching depths of more than 8,000 meters. Its biodiversity and geological activity hold immeasurable scientific value.

The 156-day expedition, led by the Institute of Deep-Sea Science and Engineering of the Chinese Academy of Sciences, set forth from Sanya, Hainan province, on Dec 6. It covered more than 40,000 kilometers — equivalent to circling the Earth — and involved 83 researchers from six countries — China, Chile, Germany, Denmark, Canada, and Spain.

During the expedition, the manned submersible Fendouzhe carried in the vessel completed 63 dives, 50 of which exceeding depths of 6,000 meters. Scientists collected a large number of biological and geological samples and high-definition underwater footage, laying a solid foundation for multidisciplinary research in hadal geology, biology, and environmental science.