| Project/Area Number |
08454163
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
地球化学
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
GAMO Toshitaka The University of Tokyo, Ocean Research Institute, Associate Professor, 海洋研究所, 助教授 (70143550)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
ISHIBASHI Junichiro Kyushu University, Faculty of Science Associat Professor, 理学部, 助教授 (20212920)
|
|---|
| Project Period (FY) |
1996 – 1998
|
| Project Status |
Completed (Fiscal Year 1998)
|
| Budget Amount *help |
¥8,900,000 (Direct Cost: ¥8,900,000)
Fiscal Year 1998: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 1997: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 1996: ¥6,500,000 (Direct Cost: ¥6,500,000)
|
|---|
| Keywords | Plate Boundary / Hydrothermal fluid / Cold Seepage / Dissolved Gas / Stable Isotope Ratio / Submersible Observation / Subduction Zone / Mid-Oceanic Ridge / ガスクロマトグラフ / 質量分析 |
|---|
| Research Abstract |
Plate boundaries on the deep seafloor, such as mid-oceanic ridges and plate subduction zones, can be regarded as openings or windows through which much amount of chemical components comes up from or goes down to the earth interior chiefly by seawater convection. Since the venting fluids have quite different characteristiecs from ambient seawater, it is suggested that the fluids should bear significant parts of chemical flux between the ocean and the lithosphere. This study has paid attention to dissolved gas components, such as methane, helium, carbon dioxide etc. in venting fluids, because their concentrations and stable isotope ratios give us much useful information on the sources of the gases associated with pore fluid behaviors. As for the cold seepage at subduction zones, this study forms a part of Japan-France KAIKO-TOKAI Project which had been successfully conducted in the eastern Nankai Trough subduction zone between 1993 and 1997. We took many pore fluid samples and bottom seawaters for their chemical characterization. We have also promoted chemical investigations for submarine hydrothermal vents at various locations of mid-oceanic ridges (East Pacific Rise, Mid-Atlantic Ridge, Indian Ridge), back-arc basins (Okinawa Trough, Mariana Trough, Manus Basin), and arc volcanoes (Myojin Knoll). Accumulated data including time-series data have elucidated complicated chatacteristics of spatial and temporal variations of hydrothermal activity in the world. We have published 29 original papers on this project so far. These results of this study will play important role as preliminary databases for more detailed researches in the future.
|
