Record gold concentration detected on the ocean floor off the coast of Japan

Research conducted in the Izu Islands region of Japan has revealed a remarkable finding regarding the role of hydrothermal systems on the ocean floor in gold formation. It has been reported that the highest concentration of gold deposits ever measured worldwide has been reached in the Higashi-Aogashima caldera, located 12 kilometers east of Aogashima Island, approximately 350 kilometers south of Tokyo.

According to the study published in the journal Scientific Reports, researchers from Shizuoka University, Waseda University, and the University of Tokyo collected rock samples from the hydrothermal fields, which were first discovered in 2015, using robotic arms. The samples were examined using secondary ion mass spectrometry, a method capable of identifying trace amounts of gold.

The analyses detected "invisible gold" deposits that cannot be seen with the naked eye or standard microscopes. The research team determined that the gold is contained within pyrite, a mineral formed when hot, metal-rich fluids erupt onto the seafloor. It was noted that the gold in the pyrite, also known as "fool's gold," is integrated into the chemical structure of the mineral as atoms or trapped in the form of nanoparticles.

According to the authors of the study, the pyrite in the Higashi-Aogashima caldera has the highest gold concentration among known samples today. The fact that the region is located at a shallower depth compared to other gold-producing hydrothermal vents that Japan plans to develop is significant in terms of accessibility and potential production value.

MINING DEBATE BACK ON THE AGENDA

The discovery has reignited debates regarding the ecological consequences of deep-sea mining. Active hydrothermal vents provide habitats for specialized marine life such as crustaceans, tube worms, sponges, corals, octopuses, and various fish species. Scientists are warning that commercial mining should not be conducted in these sensitive ecosystems.

There is currently no commercial deep-sea gold mine in operation anywhere in the world. A previous underwater mining project that was intended to be implemented off the coast of Papua New Guinea failed due to the operating company entering a financial crisis and environmental protests. It was reported that the Papua New Guinea government lost approximately 85 million dollars during this process.

While the Papua New Guinea administration has announced that it will adhere to a moratorium on deep-sea mining, some Pacific nations have also announced that they will support the moratorium until 2030. Japan, meanwhile, continues its deep-sea mining research despite political and environmental concerns.