Project/Area Number |
17540391
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Solid earth and planetary physics
|
Research Institution | The University of Tokyo |
Principal Investigator |
ICHIHARA Mie The University of Tokyo, Earthquake Research Institute, Research Associate (00376625)
|
Project Period (FY) |
2005 – 2007
|
Project Status |
Completed (Fiscal Year 2007)
|
Budget Amount *help |
¥3,750,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥150,000)
Fiscal Year 2007: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2006: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 2005: ¥2,100,000 (Direct Cost: ¥2,100,000)
|
Keywords | Fracture / Flow / Magma / Silicate melt / Compression test / Glass transition / Strain rate / Temperature |
Research Abstract |
Compression tests and three-point bending fracture tests were conducted on synthetic magma at various temperatures and strain rates that cover the glass transition condition. Based on the experimental results, behaviors of the material around the glass transition were characterized. It has been shown that transient behaviors of magma in the time-dependent stress and strain conditions cannot be expressed by the existing viscoelastic models for magma. For example, the existing models do not take account of the work-hardening behavior, though it is considered to play an important role at the transition from flow to fracture (Ichihara, et al., 2008). We also developed a new apparatus to investigate the fragmentation process of magma analogues. Using the apparatus, we made the first simultaneous observations with pressure transducers and high-speed video cameras on the fragmentation process of volcanic rock (Shoeu, et al., 2008). The theoretical part of this study has been published. Ichihara (2008) calculated expansion of a viscoelastic shell bubble by rapid decompression and presented parameters which determine the stress accumulation at the bubble wall The result has been used to analyze fragmentation experiments on magma analogues(Kameda, et al., submitted to GRL). Ichihara (2007) presents a mathematical model to represent the time-dependent behavior of magma, based on considerations of the microscopic mechanism.
|