SANYA — Chinese scientists have carried out manned deep-diving expeditions to eight major hadal trenches around the world, setting numerous world records related to manned deep-sea missions and discoveries.

This was revealed at the Second International Conference on Biology, Geology and Environment of Hadal Trenches, which opened on Thursday in Sanya, southern island province of Hainan.

The conference brought together experts from countries including Denmark, France, Portugal, New Zealand, Chile, the United States, India and Indonesia.

The world has 37 hadal trenches, which are ocean areas exceeding 6,000 meters deep. The Hadal Trench environment is characterized by high pressure, low temperatures, constant darkness, active tectonics, dense earthquakes, and strange life forms. These trenches constitute a frontier in earth sciences, particularly in marine sciences.

Chinese scientific research on hadal zones involves the use of the Fendouzhe submersible and has made remarkable progress in recent years. To date, China has carried out expeditions to the Mariana Trench, Yap Trench, Kermadec Trench, Diamantina Trench, Wallaby Trench. -Zenith Fracture Zone, the Java Trench, the Kuril-Kamchatka Trench and the Aleutian Trench.

The three-day conference is organized by the Institute of Deep Sea Science and Engineering of the Chinese Academy of Sciences.