Scientists have discovered a massive hydrogen-rich hydrothermal system beneath the western Pacific seafloor. The system was explored using the crewed submersible Fendouzhe.<\/p>\n
The system offers a\u00a0new\u00a0glimpse into deep-sea serpentinization\u2014a process in which iron- and magnesium-rich rocks chemically react with water to form serpentine minerals and release hydrogen.<\/p>\n
Scientists from the Institute of Oceanology of the Chinese Academy of Sciences (IOCAS) revealed that the system is critical to understanding Earth\u2019s internal processes and the conditions that may have fostered life\u2019s origins.<\/p>\n
Hundred times larger than the Lost City<\/p>\n
Researchers revealed that the Kunlun hydrothermal field\u2014a tectonically active site roughly 80 kilometers west of the Mussau Trench on the Caroline Plate\u2014comprises 20 large seafloor depressions<\/a> (some exceeding one\u00a0kilometer in diameter) clustered together like a pipe swarm, a group of vertical or steeply inclined cylindrical rock structures that funnel liquid or gas from Earth\u2019s interior.<\/p>\n The total area is 11.1\u00a0square kilometers, i.e., over a hundred times larger than the Lost City, a unique deep-sea hydrothermal field located on the Atlantis Massif, a section of the Mid-Atlantic Ridge.<\/p>\n \u201cThe Kunlun system stands out for its exceptionally high hydrogen flux, scale, and unique geological<\/a> setting,\u201d\u00a0said Prof. SUN Weidong, the study\u2019s corresponding author. \u201cIt shows that serpentinization-driven hydrogen generation can occur far from mid-ocean ridges, challenging long-held assumptions.\u201d<\/p>\n Larger craters were prospected<\/p>\n Published in the Science Advances, the study<\/a> reveals that the four of the larger craters were prospected using the human occupied vehicle Fendouzhe and have steep walls similar to those of kimberlite pipes, with depths of up to 130 meters. Ecosystems have been observed in smaller pits on the bottom of these pipes. Hydrogen concentrations of ~5.9 to 6.8\u00a0millimoles per kilogram in hydrothermal fluids have been obtained using in situ Raman spectra.<\/p>\n Based on discharge area mapping and flow velocity analysis, the Kunlun field\u2019s annual hydrogen flux is estimated at 4.8 \u00d7 1011 mol\/year, representing at least 5% of the global abiotic hydrogen output from all submarine sources\u2014a notable\u00a0contribution for a single system, according to a press release<\/a>.<\/p>\n Geological features\u2014including steep-walled craters resembling kimberlite pipes, explosive breccia deposits, and layered carbonate structures\u2014suggest the hydrothermal activity has followed a staged evolution: gas-driven eruptions first, followed by prolonged hydrothermal circulation and mineral deposition, as per the release.<\/p>\n \u201cWhat\u2019s particularly intriguing is its ecological potential,\u201d Prof. SUN said. \u201cWe observed diverse deep-sea life thriving here\u2014shrimp, squat lobsters, anemones, and tubeworms\u2014species that may depend on hydrogen-fueled chemosynthesis.\u201d<\/p>\n Researchers claimed that this discovery provides a natural laboratory for studying links between hydrogen emissions and primitive life\u2019s emergence. Alkaline, hydrogen-rich fluids like those at Kunlun are thought to mirror early Earth\u2019s chemical environment.<\/p>\n