Research from Waseda University has revealed that petit-spot volcanoes on the ocean floor significantly influence marine biogeochemical cycles, particularly the carbon cycle, by releasing CO2 and methane-rich alkaline magma. The study focused on a petit-spot volcano in the Japan Trench, identified as the deepest hydrothermal site known, located 5.7 km (3.5 miles) underwater. Samples taken from this site contained iron and manganese oxides, indicating hydrothermal activity, which is crucial for understanding these submarine systems.
Petit-spot volcanoes, which form where oceanic plates flex, produce alkaline magma and volcanic rock called peperite, suggesting hydrothermal fluid generation. The research team, led by Assistant Professor Keishiro Azami, analyzed the chemical and mineral composition of the samples and determined that the hydromineral compositions resulted from low-temperature hydrothermal processes. They concluded that the elemental contributions from these volcanoes could have significant implications for global biogeochemical cycles.
Moreover, the study emphasizes the need for deeper investigations into petit-spot volcanoes, as their unique geological features play a vital role in the ocean’s ecological and chemical dynamics. The findings were published in Communications Earth & Environment on June 1, 2023.
