2009 Fiscal Year Final Research Report
Geophysical and Geochemical Environment of Archean Biosphere
| Project/Area Number |
18340174
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Petrology/Mineralogy/Science of ore deposit
|
|---|
| Research Institution | Kagoshima University |
|---|
Principal Investigator |
NEDACHI Munetomo Kagoshima University, 大学院・理工学研究科(理学系), 教授 (10107849)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
NEDACHI Youko 鹿児島純心女子大学, 看護栄養学部, 教授 (80290659)
ONOUE Tetsuji 鹿児島大学, 大学院・理工学研究科(理学系), 助教 (60404472)
|
|---|
| Project Period (FY) |
2006 – 2009
|
| Keywords | ストロマトライト / 炭素同位体比 / バイオマーカー / 古地磁気 / 古環境 |
|---|
| Research Abstract |
The research was driven using the cores from the Pilbara craton in Western Australia by ABDP (Archean Biosphere Drilling Project), to understand the evolution of Archean life and geochemical environment including geomagnetism. Paleomagnetic study suggests that the geomagnetic dynamo might behave at about 3.5Ga, and that the free oxygen level was very low and iron microbes oxidized ferrous to ferric, bereaving the charge of dissolved hydrion. The carbon from organisms in ferruginous Marble Bar Chert might be depleted during diagenesis. On the other hand, the high free oxygen level of 2.77Ga, is suggested from subsistence of cyanobacteria and sulfate reduction bacteria, but the level was not enough to oxidized magnetite to ferric compounds. The behavior of organic carbon and its isotopic ratio is not known yet, and should be expected in future study.
|
-
[Journal Article] Hematite formation by oxygenated groundwater more than 2. 76 billion years ago.2009
Author(s)
Kato, Y., Suzuki, K., Nakamura, K., Hickman, A., Nedachi, M., Ohmoto, H.
-
Journal Title
Earth and Planetary Science Letters 278
Pages: 40-49
Peer Reviewed
-
-
[Journal Article] Influence of submarine fumaroles on the distribution of mercury in the sediment of Kagoshima Bay, Japan.2007
Author(s)
Tomiyasu, T., Eguchi, T., Yamamoto, M., Anazawa, K., Ando, T., Nedachi, M., Marumo, K. Sakamoto, H.
-
Journal Title
Marine Chemistry Vol.109
Pages: 173～183
Peer Reviewed
-
[Journal Article] Paleomagnetism of the Marble Bar Chert Member, Western Australia: Implications for apparent polar wander path for Pilbara craton during Archean time.2006
Author(s)
Suganuma, Y., Hamano, Y., Niitsuma, S., M. Hoashi, T. Hisamitsu, N. Niitsuma, Kodama, K, Nedachi, M.
-
Journal Title
Earth and Planetary Science Letters Vol.252
Pages: 360-371
Peer Reviewed
-
-
-
-
-
-
-
-
-
