2024-07-26
4 分钟Researchers believe they have discovered oxygen being produced 4,000 meters below the sea surface, and think polymetallic nodules—the sought-after bounty of deep-sea miners—could be the source.
Today in science from wired, the mysterious discovery of dark oxygen on the ocean floor.
Researchers believe they have discovered oxygen being produced 4000 meters below the sea surface and think polymetallic nodules, the sought after bounty of deep sea miners, could be the source.
By Mara Magistroni for more than ten years, Andrew Sweetman and his colleagues have been studying the ocean floor and its ecosystems, particularly in the Pacifics, Clary and Clipperton zone, an area littered with polymetallic nodules as big as potatoes.
These rocks contain valuable metals, lithium, copper, cobalt, manganese and nickel that are used to make batteries.
They are a tempting bounty for deep sea mining companies, which are developing technologies to bring them to the surface.
The nodules may be a prospective source of battery ingredients, but Sweetman believes they could already be producing something quite different, oxygen.
Typically, the element is generated when organisms photosynthesize, but light doesnt reach 4000 meters below the oceans surface.
Rather, as Sweetman and his team at the Scottish association for Marine Science suggest in a new paper, the nodules could be driving a reaction that produces this dark oxygen from seawater.
Sweetman first noticed something strange in 2013 with his team.
Hed been working to measure oxygen flow in confined areas within nodule rich areas of the seabed.
The flow of oxygen seemed to increase at the seafloor, despite the fact that there were no photosynthesizing organisms nearby, so much so that the researchers thought it was an instrumental anomaly.
The same finding, however, was repeated in 2021, albeit using a different measurement approach.
The scientists were assessing changes in oxygen levels inside a benthic chamber, an instrument that collects sediment and seawater to create enclosed samples of the seabed environment.
The instrument allowed them to analyze, among other things, how oxygen was being consumed by microorganisms within the sample environment.
Oxygen trapped in the chamber should have decreased over time as organisms in the water and sediment consumed it.
But it did the opposite.
Despite the dark conditions preventing any photosynthetic reactions, oxygen levels in the benthic chamber increased.
The issue needed to be investigated.
First, the team ascertained with certainty that any microorganisms capable of producing oxygen werent present.
Once they were sure, the scientists hypothesized that polymetallic nodules captured in the benthic chamber might be involved.