Could lumpy metallic rocks in the deepest, darkest reaches of the ocean be making oxygen in the absence of sunlight?
Some scientists think so, but others have challenged the claim that so-called “dark oxygen” is being produced in the lightless abyss of the seabed.
The discovery — detailed in July last year in the journal Nature Geoscience — called into question long-held assumptions about the origins of life on Earth, and sparked intense scientific debate.
Photo: AFP
The findings were also consequential for mining companies eager to extract the precious metals contained within these polymetallic nodules.
Researchers said that potato-sized nodules could be producing enough electrical current to split seawater into hydrogen and oxygen, a process known as electrolysis.
This cast doubt on the long-established view that life was made possible when organisms started producing oxygen via photosynthesis, which requires sunlight, about 2.7 billion years ago.
“Deep-sea discovery calls into question the origins of life,” the Scottish Association for Marine Science said in a press release to accompany the publication of the research.
Environmentalists said the presence of dark oxygen showed just how little is known about life at these extreme depths, and supported their case that deep-sea mining posed unacceptable ecological risks.
“Greenpeace has long campaigned to stop deep sea mining from beginning in the Pacific due to the damage it could do to delicate, deep sea ecosystems,” it said, adding: “This incredible discovery underlines the urgency of that call.
The discovery was made in the Clarion-Clipperton Zone, a vast underwater region of the Pacific Ocean between Mexico and Hawaii of growing interest to mining companies. Scattered on the seafloor 4km beneath the surface, polymetallic nodules contain manganese, nickel and cobalt, metals used in electric vehicle batteries and other low-carbon technologies.
The research that gave rise to the dark oxygen discovery was partly funded by a Canadian deep-sea mining business, The Metals Co, that wanted to assess the ecological impact of such exploration.
It has sharply criticized the study by marine ecologist Andrew Sweetman and his team as plagued by “methodological flaws.”
Metals Co environmental manager Michael Clarke said the findings “are more logically attributable to poor scientific technique and shoddy science than a never-before observed phenomenon.”
Sweetman’s findings proved explosive, with many in the scientific community expressing reservations or rejecting the conclusions.
Since July, five academic research papers refuting Sweetman’s findings have been submitted for review and publication.
“He did not present clear proof for his observations and hypothesis,” said Matthias Haeckel, a biogeochemist at the GEOMAR Helmholtz Centre for Ocean Research in Kiel, Germany. “Many questions remain after the publication. So, now the scientific community needs to conduct similar experiments etc, and either prove or disprove it.”
Olivier Rouxel, a geochemistry researcher at Ifremer, the French national institute for ocean science and technology, said there was “absolutely no consensus on these results.”
“Deep-sea sampling is always a challenge,” he said, adding it was possible that the oxygen detected was “trapped air bubbles” in the measuring instruments.
He was also skeptical about deep-sea nodules, some tens of millions of years old, still producing enough electrical current when “batteries run out quickly.”
“How is it possible to maintain the capacity to generate electrical current in a nodule that is itself extremely slow to form?” he asked.
When contacted by Agence France-Presse, Sweetman indicated that he was preparing a formal response.
“These types of back and forth are very common with scientific articles and it moves the subject matter forward,” he said.
POLITICAL PRISONERS VS DEPORTEES: Venezuela’s prosecutor’s office slammed the call by El Salvador’s leader, accusing him of crimes against humanity Salvadoran President Nayib Bukele on Sunday proposed carrying out a prisoner swap with Venezuela, suggesting he would exchange Venezuelan deportees from the US his government has kept imprisoned for what he called “political prisoners” in Venezuela. In a post on X, directed at Venezuelan President Nicolas Maduro, Bukele listed off a number of family members of high-level opposition figures in Venezuela, journalists and activists detained during the South American government’s electoral crackdown last year. “The only reason they are imprisoned is for having opposed you and your electoral fraud,” he wrote to Maduro. “However, I want to propose a humanitarian agreement that
ECONOMIC WORRIES: The ruling PAP faces voters amid concerns that the city-state faces the possibility of a recession and job losses amid Washington’s tariffs Singapore yesterday finalized contestants for its general election on Saturday next week, with the ruling People’s Action Party (PAP) fielding 32 new candidates in the biggest refresh of the party that has ruled the city-state since independence in 1965. The move follows a pledge by Singaporean Prime Minister Lawrence Wong (黃循財), who took office last year and assumed the PAP leadership, to “bring in new blood, new ideas and new energy” to steer the country of 6 million people. His latest shake-up beats that of predecessors Lee Hsien Loong (李顯龍) and Goh Chok Tong (吳作棟), who replaced 24 and 11 politicians respectively
Young women standing idly around a park in Tokyo’s west suggest that a giant statue of Godzilla is not the only attraction for a record number of foreign tourists. Their faces lit by the cold glow of their phones, the women lining Okubo Park are evidence that sex tourism has developed as a dark flipside to the bustling Kabukicho nightlife district. Increasing numbers of foreign men are flocking to the area after seeing videos on social media. One of the women said that the area near Kabukicho, where Godzilla rumbles and belches smoke atop a cinema, has become a “real
‘WATER WARFARE’: A Pakistani official called India’s suspension of a 65-year-old treaty on the sharing of waters from the Indus River ‘a cowardly, illegal move’ Pakistan yesterday canceled visas for Indian nationals, closed its airspace for all Indian-owned or operated airlines, and suspended all trade with India, including to and from any third country. The retaliatory measures follow India’s decision to suspend visas for Pakistani nationals in the aftermath of a deadly attack by shooters in Kashmir that killed 26 people, mostly tourists. The rare attack on civilians shocked and outraged India and prompted calls for action against their country’s archenemy, Pakistan. New Delhi did not publicly produce evidence connecting the attack to its neighbor, but said it had “cross-border” links to Pakistan. Pakistan denied any connection to
RSS