Learning more about the ecosystems along the active vents at the Mid-Atlantic Ridge at 2000 m water depth

This high-temperature hydrothermal vent field was discovered during the expedition on Puy des Folles Seamount in the Mid-Atlantic Ridge, at approximately 2000 meters deep. Within hydrothermal vents, seawater chemically altered through water-rock interactions at high temperatures is expelled through geological formations called chimneys.

An international research team has discovered 3 new fields of hydrothermal chimneys with rich biological communities using chemical energy instead of sunlight

Scientists have discovered 3 new hydrothermal vent fields over a 434-mile-long stretch of the Mid-Atlantic Ridge during the first scientific expedition aboard Schmidt Ocean Institute’s recently launched research vessel “Falkor (too)“. The discovery of the active vents is the first on this section of the world‘s longest underwater mountain range in more than 40 years. The tallest black smoker chimney was about 20 meters high.

The multidisciplinary science team representing 11 institutions from the United States, Canada, and France used advanced ocean technologies. The autonomous and remotely operated underwater vehicles mapped 65 square miles (170 square kilometers) of the seafloor at one-meter scale resolution, an area approximately the size of the Manhattan peninsula.

The Mid-Atlantic Ridge. Source: <a href="https://commons.wikimedia.org/"target="_blank">Wikimedia Commons</a>, <a href=" https://en.wikipedia.org/wiki/Creative_Commons_license"target="_blank">Creative Commons License</a>

The Mid-Atlantic Ridge stretches from Greenland to close to Antarctica on the seafloor in more or less the middle of the Atlantic. In its Northern part, it separates the North American from the Eurasian and the African plates, on the Southern hemisphere the South American from the African plate.

The Mid-Atlantic ridge is a target area for deep-sea mining and exists in international waters, also known as “The High Seas”. All mineral-resources-related activities in the area are regulated by the International Seabed Authority (ISA), established by the United Nations.

The ISA is currently considering whether to allow deep-sea mining.

Many creatures life around hydrothermal vents - such as tube worms, mussels, or shrimps - have symbiotic relationships with chemosynthetic bacteria.This Magnapinna squid - also known as Bigfin squid - was seen at approximately 2000 m depth.

Active hydrothermal vents are rich in metal sulfide deposits – mineral ore often affiliated with copper and zinc. In exploring the vents, scientists found rich biological communities teeming with marine life, including massive swarms of vent shrimp and a rare sighting of big fin squid. Many species found on vents use chemical energy (chemosynthesis) instead of sunlight, which doesn’t reach those depths.

Scientists are still learning about how these ecosystems function and the role they play for cycling carbon on our planet. The impacts deep-sea mining would have on hydrothermal vent ecosystems are unknown.

“Regional Environmental Management Plans for regulating ocean mining require accurate scientific data on the presence of animal communities and an understanding of how sites are colonized,” said Chief Scientist, Dr. David Butterfield, Principal Research Scientist with the Cooperative Institute for Climate, Ocean, and Ecosystem Studies at the University of Washington and Group Leader for the Earth Ocean Interactions Program at NOAA Pacific Marine Environmental Lab in Seattle.

“There is some agreement that sites with active venting and chemosynthetic vent fauna communities should be excluded from mining because of the very limited extent of this habitat, which is restricted to a narrow band of activity on the global mid-ocean ridge system.”

The vessel’s inaugural 40-day expedition began in March 2023. The ship will be utilized for global ocean exploration, focused on a new region each year.

“The discoveries on this expedition underscore how much we have yet to learn about deep-sea ecosystems – and why, before marching ahead with mining or other potentially damaging activities, we need to learn more about our unknown ocean, “ said Wendy Schmidt, co-founder and president of Schmidt Ocean Institute.

One of the discovered vent fields was located at the Puy des Folles volcano and has 5 active sites over 6.95 square miles (18 square kilometers). High-temperature ‘black smoker’ vents were also found at the Grappe Deux vent system and Kane Fracture Zone.

Schmidt Ocean Institute

International Seabed Authority

Photos: Schmidt Ocean Institute

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(27.04.2023, USA: 04.27.2023)