[M-IS22] 海底のメタンを取り巻く地圏-水圏-生命圏の相互作用と進化

[MIS22-02] Chemistry, Observation and Ecology of Submarine Seeps (COESS): Research and activities related to a UN Ocean Decade action plan.

*Glen Snyder¹、Hitoshi Tomaru²、Shinsuke Aoki³、Teresa Nakajima⁴、Shiono Miki¹、Takanori Kagoshima⁶、Ryo Matsumoto⁵ (1.Atmosphere and Ocean Research Institute, University of Tokyo、2.Department of Earth Sciences, Chiba University、3.Faculty of Agriculture, Kagawa University、4.Marine Core Research Center, Kochi University、5.Gas Hydrate Research Laboratory, Meiji University、6.University of Toyama)

キーワード：Ocean Decade, seafloor lander, Sea of Japan, methane seep, Torigakubi Spur, seafloor drone

Project COESS (Chemistry, Observation, and Ecology of Submarine Seeps) was established in 2022 as part of the United Nations Decade of Ocean Science for Sustainable Development. The project currently involves members of 12 different research institutions. In addition to promoting research of seafloor seeps, the group also aims to involve communities in coastal areas and to create educational materials which will promote awareness of these unique seafloor environments. Over the past year we have deployed a seafloor drone to collect video footage of life around seeps in Joetsu Basin, Sea of Japan. In October, 2023 we deployed 2 Fugro Shallow Environmental Landers at Torigakubi Spur, a previously documented seep site in located roughly 30km offshore, at 560m water depth. The landers are equipped with instrumentation including CTD, ADCP, and instrumentation to measure pH, oxygen and methane concentrations, and turbidity. Since Torigakubi Spur is located only 50km from the January 1 Noto Earthquake and subsequent aftershocks, we hope to determine what response the methane seeps had to seismic activity after the landers are recovered this summer. We hope this project will be a model for future long-term seep studies in Japan as well as being an example of community involvement in learning more about the sea floor.