Self-diffusion in high-pressure ices and implications for plastic flow in the interiors of the large icy bodies
| Project/Area Number |
15K17795
|
|---|
| Research Category |
Grant-in-Aid for Young Scientists (B)
|
| Allocation Type | Multi-year Fund |
|---|
| Research Field |
Geochemistry/Cosmochemistry
|
|---|
| Research Institution | Okayama University |
|---|
Principal Investigator |
Noguchi Naoki 岡山大学, 惑星物質研究所, 特別契約職員(助教) (50621760)
|
|---|
| Project Period (FY) |
2015-04-01 – 2017-03-31
|
| Project Status |
Completed (Fiscal Year 2016)
|
| Budget Amount *help |
¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000)
Fiscal Year 2016: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2015: ¥3,250,000 (Direct Cost: ¥2,500,000、Indirect Cost: ¥750,000)
|
|---|
| Keywords | 高圧氷 / 拡散 / レオロジー / 氷天体 / 粘性 / プロトン / ラマン分光 |
|---|
| Outline of Final Research Achievements |
The lifetimes of the internal ocean of large icy bodies till water freezes depend on the rheological properties of the high pressure polymorphs of H2O ice layers (HP-ice layer) underlying the internal oceans. The differential stress driving the conventions of the HP-ice layers is very low below 0.1 MPa. The rheological properties at low-stress condition can be inferred from their diffusivities and the theory of diffusion creep. Here, we have developed the method to determine diffusion coefficients of the high-pressure ices using a DAC and micro-Raman spectroscopy. First, to conduct the diffusion experiments, we have constructed the instrumental platforms such as a micro-Raman mapping system, and a Peltier-cooling DAC. Further, we determined the pressure-temperature dependences of the diffusion coefficients of ices VI and VII. The viscosities of HP-ices were inferred from their diffusivities, and the critical layer thickness below which convection cannot occur was estimated.
|
Report
(3 results)
Research Products
(7 results)
