Zobrazeno 1 - 10
of 66
pro vyhledávání: '"Tomohiro Toki"'
Publikováno v:
Frontiers in Earth Science, Vol 11 (2023)
Methane is a greenhouse gas, and the East China Sea acts as a source of emissions to the atmosphere. On the other hand, the distribution of methane concentration in the Ryukyu Arc shelf and forearc region has not been clarified. Therefore, we investi
Externí odkaz:
https://doaj.org/article/06b0d58be07d42ffab1e230640ad65ee
Autor:
Miho Asada, Mikiya Yamashita, Rina Fukuchi, Toshiyuki Yokota, Tomohiro Toki, Akira Ijiri, Kiichiro Kawamura
Publikováno v:
Frontiers in Earth Science, Vol 11 (2023)
We identified 27 new mud volcanoes, including potential ones, in a part of the Hyuga-nada area, southwest offshore Japan, at the northern end of the Ryukyu Trench, based on subseafloor geological structures using geophysical investigations. These mud
Externí odkaz:
https://doaj.org/article/e18705072eea4bf084472cc5e7584d06
Publikováno v:
Scientific Reports, Vol 13, Iss 1, Pp 1-12 (2023)
Abstract The helium isotope ratio (3He/4He), concentration ratio of neon-20 to helium-4 (20Ne/4He), argon (Ar), krypton (Kr), and xenon (Xe) concentrations were measured in the porewater of surface sediments of several submarine mud volcanoes. From t
Externí odkaz:
https://doaj.org/article/c8467a52c27948f8b163ec874a509ec3
Publikováno v:
Frontiers in Marine Science, Vol 10 (2023)
Mud volcanoes can cause various geohazards, so it is very important to know their activity level and their distribution. Surface sediments were collected from four submarine mud volcanoes (MVs) off Tanegashima (SW Japan), namely, MV1, MV2, MV3, and M
Externí odkaz:
https://doaj.org/article/138934aa209740ffbf3b81e97b7f9e86
Autor:
Tomohiro Toki, Tasuku Nohara, Yoshiaki Urata, Ryuichi Shinjo, Shuko Hokakubo-Watanabe, Jun-ichiro Ishibashi, Shinsuke Kawagucci
Publikováno v:
Progress in Earth and Planetary Science, Vol 9, Iss 1, Pp 1-19 (2022)
Key points The Sr isotopic ratios of hydrothermal fluids from the Okinawa Trough are exceptionally high. The enrichment of 87Sr at Yonaguni Knoll IV cannot be explained without the influence of terrestrial clay minerals in sediments. High Sr isotopic
Externí odkaz:
https://doaj.org/article/20fa82020f3444fa950a64c4469e968e
Autor:
Akira Ijiri, Ryoma Setoguchi, Yuki Mitsutome, Tomohiro Toki, Masafumi Murayama, Kyoko Hagino, Yohei Hamada, Takeyasu Yamagata, Hiroyuki Matsuzaki, Wataru Tanikawa, Osamu Tadai, Kazuya Kitada, Tatsuhiko Hoshino, Takuro Noguchi, Juichiro Ashi, Fumio Inagaki
Publikováno v:
Frontiers in Earth Science, Vol 11 (2023)
Mud volcanoes are topographic features through which over-pressurized sediments are intruded upward and erupted, transporting fluids and sediments from the deep subsurface to the surface/seafloor. To understand material and biogeochemical cycling thr
Externí odkaz:
https://doaj.org/article/91a8207ba86e420e8ab089ff145e49d4
Publikováno v:
Journal of Hydrology: Regional Studies, Vol 40, Iss , Pp 101051- (2022)
Study region: Spring along the southeast coast of Yonaguni Island, located at the western end of the Ryukyu forearc. Study focus: The chemical composition of groundwater, including SF6 concentration, was investigated to clarify the mechanism of groun
Externí odkaz:
https://doaj.org/article/84780ebc2bf54bcba22b6008ecfe2583
Publikováno v:
Progress in Earth and Planetary Science, Vol 6, Iss 1, Pp 1-14 (2019)
Abstract Concentrations of arsenic (As) and its chemical forms were determined on deep-sea sediments drilled at three sites of Nankai Trough, off the Kii Peninsula, Japan. Those sediments were analyzed to document the behavior of As in relation to me
Externí odkaz:
https://doaj.org/article/660344f845f545d68ffab184c3c2c57c
Autor:
Tatsuhiko Hoshino, Tomohiro Toki, Akira Ijiri, Yuki Morono, Hideaki Machiyama, Juichiro Ashi, Kei Okamura, Fumio Inagaki
Publikováno v:
Frontiers in Microbiology, Vol 8 (2017)
Submarine mud volcanoes (SMVs) are formed by muddy sediments and breccias extruded to the seafloor from a source in the deep subseafloor and are characterized by the discharge of methane and other hydrocarbon gasses and deep-sourced fluids into the o
Externí odkaz:
https://doaj.org/article/f7bf836c6bab4d8dae3022bfe3d73e97
Autor:
Akira Ijiri, Fumio Inagaki, Ryoma Setoguchi, Yuki Mitsutome, Yohei Hamada, Tomohiro Toki, Masafumi Murayama, Kyoko Hagino
Publikováno v:
Goldschmidt2022 abstracts.