"Dark Oxygen" Found on Seafloor

This is a brain twister. Previously sunlight was considered necessary to produce oxygen, and element most life on Earth needs to survive. Plants engaged in photosythesis produce O₂ in the chemical process used to create energy. Scientists researching the deep ocean bed between Mexico and Hawaii have discovered that metalic nodules lying on the sea floor produce oxygen without sunlight. These nodules are the subject of efforts to mine the seafloor for minerals needed in battery production. But the new discovery poses a problem for miners. The oxygen producing nodules may be required to support life in the ocean. The discovery was published in the science journal, Nature Geoscience Nodules form when disolved metals in seawater deposit on shell fragments or other debris. It is a process that takes millions of years. The nodules contain copper, cobalt and lithium, which are needed to produce batteries. 

Companies are developing technology to bring the stones to the surface from thousands of feet underwater. Researchers think that the metalic nodes act like batteries that spilt water molecules into their components, oxygen and hydrogen. They tested this hypothesis in the lab measuring the electric current on the surface of potato sized nodes, which equaled the voltage produced by a size AA battery. [photo credit: C. Bridgewater] The seafloor in certain areas is littered with thousands of these nodes that could be enough to electrolyze seawater. The US Oceanic and Atmospheric Administration (NOAA) has already warned that seabed mining could destroy sea life and disrupt a fragile habitat. The Clarion-Clipperton Zone where the discovery was made, is already being explored by a number of companies. 800 marine scientists from 44 country have signed a letter asking for a pause in mining efforts. Less is known about the deep sea than the surface of the Moon, and new species are discovered frequently.