Arctic & Antarctica
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ARC - Arctic Hydrothermal Vent Site Could Help in Search for Extraterrestrial Life

Site Also Expands Estimates of Seafloor Mineral Deposits

Newswise — Woods Hole, Mass. (Nov. 1, 2022) - When scientists discovered a hydrothermal vent site in the Arctic Ocean’s Aurora hydrothermal system in 2014, they did not immediately realize just how exciting their discovery was.

“Although finding any vent in the Arctic Ocean was a first, we figured what we had found was one of the least interesting kinds of vent sites that there are,” said Chris German, senior scientist with the Woods Hole Oceanographic Institution’s Department of Geology and Geophysics. “We came home from the expedition thinking, ‘Okay, we found a site in the Arctic. That’s great, but if you take away the ice-cover, it is just another vent site’.”

However, after further analysis and a follow-on 2019 expedition to the remote site, German and other researchers now think this is a very significant finding. They believe that this vent—and others still to be located within the Arctic Ocean’s Gakkel Ridge rift-valley floor—could change our understanding of ultra-slow spreading mid-ocean ridges, substantially expand the estimates of valuable marine mineral deposits rich in copper and gold and serve as natural laboratories to help inform the search for extraterrestrial life.

“Our findings have implications for ultra-slow ridge cooling, global marine mineral distributions, and the diversity of geologic settings that can host abiotic organic synthesis–pertinent to the search for life beyond Earth,” according to the paper, “Volcanically hosted venting with indications of ultramafic influence at Aurora hydrothermal field on Gakkel Ridge,” published in Nature Communications.

“The single biggest part of what we may have discovered is a vent site beneath an ice-covered ocean that is also a great place to study organic synthesis relevant to the origin of life and the search for life beyond Earth,” said German, who is lead author of the paper. “The combination of studying the geology of the seafloor and the chemistry of the overlying water column is what gives us particular insights into this vent site and reveals that it has these special qualities.”

The vent site could be a natural laboratory to prepare for exploring the Saturnian moon of Enceladus, Jupiter’s moon Europa, and other Solar System bodies with subsurface oceans that could provide conditions of habitability for life, he said.

The advance in our understanding about subsurface minerals also is significant, according to German.

The findings about the vent site “suggest that hydrothermal mineral deposits that could be economically viable in the future--because of, for instance, the high levels of  copper and gold present in the deposits -- might be a lot more abundant along one-half of all the world’s ridge crests than we have previously appreciated,” he said. “This is a class of vent sites that previously had been dismissed as unable to sustain the growth of large hydrothermal mineral deposits. Until now, scientists assumed that such small volcanic systems could not sustain hydrothermal circulation for long enough to grow such large mineral deposits.”

Regarding marine mining, German said, “As scientists, we feel that we that we should get this information out to decision makers, such as the International Seabed Authority, so that they can make informed decisions with a better understanding of the natural world.”

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