300°C liquid seeps from chimney-like vents deep in Arctic Ocean

About 3,000 metres (9,843 feet) below the Arctic Ocean, scientists are exploring a bubbling field of hydrothermal vents along the Kneipovich Mountain Range near Svalbard, the northernmost settlement on Earth.

A hydrothermal vent field has recently been discovered on the seafloor within the triangle between Greenland, Norway and Svalbard on the boundary of the North American and European tectonic plates.

Using a remotely controlled submarine, researchers at the University of Bremen’s Centre for Marine Environmental Sciences collected samples and data from the hydrothermal vent field, which they named Jøtul after a giant in Norse mythology.

Hydrothermal vents are found at the intersections of moving tectonic plates where geothermal activity is most intense. These vents form when water breaks through the ocean floor and is heated by molten magma from the planet’s interior. The superheated water then rises back to the seafloor through cracks and fissures, becoming enriched with minerals and dissolved materials from the oceanic crustal rocks.

Despite being a major intersection of tectonic plates, hydrothermal vents were not previously known to exist on the Knippovich Range – until now.

The Kneipovich chain is particularly special because it was not formed by two plates colliding together, but by two plates moving away from each other at a rate of less than 2 cm (less than an inch) per year, known as an extended chain.

Little is known about hydrothermal activity on slow-spreading ridges, so the team is keen to learn about the chemical composition of the seeping fluids, as well as the geological features formed by their heat and minerals.

Some of the fluids flowing from the Jotul field are incredibly hot, reaching temperatures of 316 degrees Celsius (601 degrees Fahrenheit). When the superheated fluid comes into contact with cold water, the minerals solidify, forming huge chimney-like structures called black smokers.

Another interesting feature of the Jotul field is that its hydrothermal fluids are rich in methane, a powerful greenhouse gas, as well as carbon dioxide, the primary greenhouse gas. This means that the area could have some impact on climate change and the ocean carbon cycle.

Often, strange and bizarre life forms can inhabit hydrothermal vent fields. In the dark depths of the ocean where photosynthesis is impossible, hydrothermal fluids provide the basis for chemosynthetic organisms, which obtain nutrients through chemical energy rather than sunlight.

A thorough understanding of the biodiversity in this area is not yet available, although it will undoubtedly be a point of interest for researchers at Marum, who plan to return to the area in late summer 2024.

The study was published in the journal Scientific reports.