Scientists are investigating hydrothermal vent seeps along the Knipovič Ridge near Svalbard, the northernmost settlement on Earth, about 3,000 meters (9,843 feet) below sea level in the Arctic Ocean.
Hydrothermal vents have recently been discovered on the seafloor within the Greenland-Norway-Svalbard triangle, at the boundary between the North American and European plates.
Researchers from the University of Bremen’s Center for Marine Environmental Science (MARUM) used a remotely operated submarine to collect samples and data from the hydrothermal vent site, which they named Jötul, after a giant in Norse mythology.
Hydrothermal vents are found at the joints of moving plates, where geothermal activity is most active. Hydrothermal vents form when water seeps into the ocean floor and is heated by magma welling up from deep within the Earth. The superheated water then flows back down to the ocean floor through cracks and fissures, enriched with minerals and materials dissolved from the rocks of the ocean crust.
Despite being a major plate joint, the Knipovich Ridge was not previously known to host hydrothermal vents.
Some of the hydrothermal cones were home to organisms including small crustaceans.
Image courtesy of MARUM/University of Bremen
The Knipovich Ridge is especially special because it was not formed by two plates colliding, but rather by two plates moving apart at a rate of less than 2 centimeters (1 inch) per year, known as a spreading ridge.
Little is known about hydrothermal activity in slowly spreading ocean ridges, so the team wants to learn more about the chemical composition of the outflowing fluids and the geological features shaped by their heat and minerals.
Some of the fluids that bubble up from the Jötul oil field are incredibly hot, reaching up to 316 °C (601 °F). When the superheated fluids come into contact with frigid water, the minerals solidify, forming large chimney-like structures called black smokers.
Another interesting feature of the Jötul field is that its hydrothermal fluids are rich in not only carbon dioxide, the primary greenhouse gas, but also methane, a powerful greenhouse gas, meaning that the region could have some impact on climate change and the ocean carbon cycle.
The areas around hydrothermal vents are often home to strange and mysterious life forms: in the pitch black depths of the ocean, where photosynthesis is not possible, the hot water provides the basis for chemosynthetic organisms, which derive their nutrients from chemical energy rather than sunlight.
The biodiversity of the area is yet to be fully explored, but it will undoubtedly be of interest to MARUM researchers, who plan to return to the region in late summer 2024.
The study has been published in the journal Scientific Reports.