Pioneering Human Dives to the Gakkel Ridge in the Arctic Ocean

The Gakkel Ridge is an ultraslow-spreading mid-ocean ridge located beneath perennial Arctic sea ice at water depths exceeding 5,000 m. Its extremely low spreading rate, sparse magmatism, and permanent ice cover have long limited geophysical detection, direct observation, and sampling. Exploration is further constrained by drifting sea ice that prevents emergency surfacing, under-ice navigation and communication challenges, extreme cold, short operational windows, and the absence of nearby rescue infrastructure. As a result, large portions of the ridge have remained poorly explored for decades.

Here we report the scientific and technical achievements of a recent Chinese-led expedition to the eastern Gakkel Ridge, representing the first intensive manned geological and biological investigation of this remote polar environment. Using the deep-diving human-occupied vehicle Fendouzhe, more than 43 successful dives were conducted beneath Arctic sea ice, reaching maximum depths greater than 5,200 m. These dives enabled unprecedented in situ observations and direct sampling of seafloor geology, hydrothermal features, and associated ecosystems. We present initial geological and biological results and discuss their implications for understanding crustal accretion, hydrothermal activity, and ecosystem development at ultraslow-spreading ridges in polar settings.

Rerences:

Alexandra Witze, Nature 647, 564-565 (2025) doi: https://doi.org/10.1038/d41586-025-03679-0