2009 Fiscal Year Final Research Report
Phase changes of methane hydrate under high-temperature and pressure and inference of interiors of giant icy planets
| Project/Area Number |
18340126
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Solid earth and planetary physics
|
|---|
| Research Institution | University of Tsukuba |
|---|
Principal Investigator |
HIRAI Hisako University of Tsukuba, 地球深部ダイナミクス研究センター, グローバルCOE教授 (60218758)
|
|---|
| Co-Investigator(Renkei-kenkyūsha) |
YAMAMOTO Yoshitaka 産業技術総合研究所, メタンハイドレートセンター, チームリーダー (80358283)
|
|---|
| Project Period (FY) |
2006 – 2009
|
| Keywords | 内部構造 |
|---|
| Research Abstract |
This study intended firstly to clarify phase changes and properties of methane hydrate and solid methane under high-pressures and high-temperatures comparable to those of interiors of icy planets and satellites, and then to infer the states and internal structures of the icy bodies based on the experimental results. High-pressures and high-temperatures were generated by using laser heated diamond anvil cells (LHDAC), and characterization of the samples were made by X-ray diffractometry and Raman spectroscopy. For methane hydrate, the high-pressure phase of filled ice Ih structure survived at least up to 90 GPa. The reasons for the remarkable high-pressure stability were examined. The orentaional ordering of guest methane molecules and symmetrization of hydrogen bond of host molecules might substantiate the outstanding stability of the filled ice Ih structure under extremely high pressure. For solid methane, X-ray diffractometry and Raman spectroscopy revealed the melting conditions to be above approximately 1100 K in a wide pressure range of 10 to 80 GPa. Above 1100 K, polymerizations occurred to produce ethane molecules and further polymerized hydrocarbons. Above 3000 K, diamond was produced. These changes proceeded depending on temperature rather than on pressure. The present study provides some experimental supports to theoretical predictions that the middle ice layer of giant planets such as Neptune and Uranus melts into a hot methane-rich ocean, and will help to improve our understanding of the chemical process of the giant planets' interiors.
|
-
-
-
-
[Journal Article] Polymerization of methane molecules and release of hydrogen under the Earth's mantle conditions.2010
Author(s)
Shinozaki, A., Hirai, H., Kagi, H., Hamane, D., Kondo, T. Yagi, T.
-
Journal Title
J. Phys. : Conf. Ser. 215
Pages: 012104
-
-
-
-
-
-
-
-
[Journal Article] Imaging and density mapping of tetrahydrofuran clathrate hydrates by phase-contrast X-ray computed tomography2007
Author(s)
Takeya, S., Honda, K., Kawamura, T., Yamamoto, Y., Yoneyama, A., Hirai, Y., Hyohdo, I., Takeda, T.
-
Journal Title
Appl. Phys. Lett. 90
Pages: 081920-1-081920-3
-
-
[Journal Article] Raman spectra of methane hydrate up to 86 GPa, Phys.2007
Author(s)
Machida, S., Hirai, H., Kawamura, T., Yamamoto, Y., Yagi, T.
-
Journal Title
Chem. Minerals 34
Pages: 31-35
-
-
-
-
-
-
[Journal Article] Highly Selective Encaging of Carbon Dioxide Molecules in the Mixed Carbon Dioxide and Nitrogen Hydrate at Low Temperatures2006
Author(s)
Ji-Ho Yoon, Kawamura, T., Ohtake, M., Takeya, S., Komai, T., Yamamoto, Y.
-
Journal Title
J. Phys. Chem. B 110
Pages: 17595-17599
-
[Presentation] Stability of CO2 hydrate under very high pressure and low temperature2009
Author(s)
Hirai, H., Honda, M., Kawamura, T., Yamamoto, Y., Yagi, T.
Organizer
American Geophysical Union Fall Meeting 2009
Place of Presentation
San Francisco, CA, USA
Year and Date
2009-12-16
-
-
-
-
-
[Presentation] Structural Changes and Intermolecular Interactions of Filled Ice Ic Structure for Hydrogen Hydrate under High Pressure2009
Author(s)
Machida, S., Hirai, H., Kawamura, T., Yamamoto, Y., Yagi, T.
Organizer
AIRAPT-22 & HPCJ-50, odaiba
Place of Presentation
Tokyo, Japan
Year and Date
2009-07-30
-
[Presentation] Changes in structure and preferential cage occupancy of ethane hydrate and methane-ethane mixed gas hydrate under high pressure2009
Author(s)
Hirai, H., Takahara, N., Kawamura, T., Yamamoto, Y., Yagi, T.
Organizer
AIRAPT-22 & HPCJ-50, odaiba
Place of Presentation
Tokyo, Japan
Year and Date
2009-07-30
-
[Presentation] Polymerization of methane molecules and release of hydrogen under the Earth's mantle conditions2009
Author(s)
Shinozaki, A., Hirai, H., Kagi, H., Hamane, D., Kondo, T., Yagi, T.
Organizer
AIRAPT-22 & HPCJ-50, odaiba
Place of Presentation
Tokyo, Japan
Year and Date
2009-07-30
-
[Presentation] Structural changes and intermolecular interactions for hydrogen hydrate under high pressure2009
Author(s)
Machida, S., Hirai, H., Kawamura, T., Yamamoto, Y., Yagi, T.
Organizer
GRC-BGI Workshop on Deep Earth Mineralogy
Place of Presentation
Bayreuth, Germany
Year and Date
2009-06-18
-
[Presentation] Polarization of methane molecule and reaction between released hydrogen and olivine in the Earth's mantle2009
Author(s)
Shinozaki, A., Hirai, H., Hamane, D., Kagi, H., Kondo, T., Yagi, T.
Organizer
GRC-BGI Workshop on Deep Earth Mineralogy
Place of Presentation
Bayreuth, Germany
Year and Date
2009-06-18
-
-
-
[Presentation] Developing high-pressure neutron diffraction techniques for a pulsed neutron facility2009
Author(s)
Kagi, H., Okuchi, T., Uwatoko, Y., Sasaki, S., Kondo, T., Arima, H., Osakab, T., Hirai, H., Yamamuro, O.
Organizer
Japan Geoscience Union Meeting 2009
Place of Presentation
Makuhari, Japan
Year and Date
2009-05-16
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
[Presentation] 固体メタンの高圧相変化2008
Author(s)
小長井敬介, 平井寿子, 川村太郎, 山本佳孝, 八木健彦, 亀卦川卓美
Organizer
第25回PFシンポジウム, 高エネルギー加速器研究機構
Place of Presentation
国際交流センター
Year and Date
2008-03-18
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
[Presentation] ガスハイドレートの高圧安定性と相互作用2006
Author(s)
平井寿子, 町田真一, 川村太郎, 山本佳孝, 八木健彦
Organizer
東大物性研短期研究会J-PARK研究会「水、氷、水素を基調とした地球惑星科学と物性科学」
Place of Presentation
東京大学物性研究所中性子科学研究施設(東海村
Year and Date
2006-10-24
-
-
-
-
-
-
-
-
-
-
