Chinese scientists completed the first extensive crewed exploration of the eastern Gakkel Ridge, conducting 40+ dives with the submersible Fendouzhe and reaching 5,277 m. Early findings suggest the area may host hydrothermal vents similar to those on the western ridge, which support unusual ecosystems and inform astrobiology. The team collected rock, water and biological samples that will be analysed over several years. Outside experts say the work could yield major new insights into Arctic seafloor geology and life.
Chinese Expedition Makes First Crewed Survey of Eastern Gakkel Ridge — Possible Hydrothermal Vents Found
Chinese scientists completed the first extensive crewed exploration of the eastern Gakkel Ridge, conducting 40+ dives with the submersible Fendouzhe and reaching 5,277 m. Early findings suggest the area may host hydrothermal vents similar to those on the western ridge, which support unusual ecosystems and inform astrobiology. The team collected rock, water and biological samples that will be analysed over several years. Outside experts say the work could yield major new insights into Arctic seafloor geology and life.
04:15 AM, 11/14/2025Science
Chinese team completes first intensive crewed survey of the eastern Gakkel Ridge
Chinese scientists have completed the first intensive crewed exploration of a remote section of the Arctic Ocean’s Gakkel Ridge, deploying the deep-diving submersible Fendouzhe beneath sea ice to investigate an underwater volcanic mountain chain that helps drive plate tectonics.
The expedition, organized by China’s Ministry of Natural Resources and the Chinese Academy of Sciences and wrapped up late last month, focused on the ridge’s eastern segment. The team carried out more than 40 crewed dives and reached a maximum depth of 5,277 metres, collecting rock, water and biological samples for detailed laboratory analysis.
Potential hydrothermal activity and scientific importance
Preliminary results suggest this eastern section may host hydrothermal (hot-water) vents on the seabed. Hydrothermal systems discovered on the better-studied western Gakkel Ridge support unusual, sunlight-independent ecosystems and are among the best analogues for possible life in icy oceans elsewhere in the solar system, such as beneath the ice of Jupiter’s moon Europa.
“It’s the last piece of the puzzle,” said Xiaoxia Huang, a marine geophysicist at the Institute of Deep-Sea Science and Engineering in Sanya, China, who led the mission. Scientists will spend the coming years studying the samples and data.
How the mission worked
The mission paired the crewed submersible Fendouzhe with an icebreaker. Although Fendouzhe has previously visited extreme locations such as the Mariana Trench, this was its first operation in the Arctic. Each dive carried three people — typically two pilots and one scientist — and the submersible was launched through temporary openings (leads) in the pack ice.
After working on the seafloor, the vehicle ascended to roughly 150–200 metres below the surface and used cameras and multi-beam sonar to scan for an opening in the ice above. When no opening was visible, the icebreaker cleared floating ice to create a hole for surfacing. Using a crewed submersible in this environment is technically demanding because shifting sea ice can trap a vehicle, which is why earlier surveys often relied on remotely operated vehicles.
Scientific aims and next steps
Dive sites were targeted for geological interest — including seamounts and cliffs — and teams also documented fish and other marine life. Researchers will now conduct detailed analyses of the recovered rocks, water and organisms to characterise geology, chemistry and biology. Results from this work could yield major new insights into how life survives under extreme pressure, in cold darkness, and how slow-spreading ridges generate sufficient heat and chemical energy to sustain hydrothermal systems.
Outside experts welcomed the work. “It’s so hard to get there that anything anybody does is almost guaranteed to be exciting and different and new,” said Christopher German, a marine geochemist at the Woods Hole Oceanographic Institution. Elmar Albers of the Alfred Wegener Institute added that the Chinese expedition is well positioned to produce important new findings.
Huang declined to provide detailed confirmation of hydrothermal vents while analyses continue. This article is reproduced with permission and was first published on November 12, 2025.