Study on fluid dynamics of gaseous transfer in magma chambers
| Project/Area Number |
04640732
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
鉱物学(含岩石・鉱床学)
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| Research Institution | University of Tokyo |
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Principal Investigator |
KOYAGUCHI Takehiro Earthquake Research Institute, University of Tokyo Associate Professor, 地震研究所, 助教授 (80178384)
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| Project Period (FY) |
1992 – 1993
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| Project Status |
Completed (Fiscal Year 1993)
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| Budget Amount *help |
¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 1993: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1992: ¥1,200,000 (Direct Cost: ¥1,200,000)
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| Keywords | Magma chamber / Volcanic gas / Multiphase flow / Volatile component / Magma mixing / Particle settling / Fractional crystallization / Convection |
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| Research Abstract |
The following two types of experiments were conducted in order to investigate fluid dynamics of gaseous transfer in magma chambers.
The first series of the experiments is those on the effect of solid or gas particles on convection in magma chamber using small heavy particles in convecting fluid. The results show that when the concentration of particles is sufficiently small convection is basically unaffected by their presence ; however, when the concentration is above a critical value, the convective motion is considerably altered. Theoretical analyzes suggest that the mode of convection is accounted for the evolution of bulk density of the particle and liquid mixture. This result is published in Journal of Volcanology and Geothermal Research.
The second series of experiments were designed to investigate how the gas bubbles migrate into the more viscous upper layr from a less viscous lower layr in a two layr magma chamber which exsolves volatiles as it crystallizes. The results shows that bubbles form a thin form layr at the interface which becomes gravitationally unstable, giving rise to two phase plumes which rise and produce a coarse mixture of the liquid. Theoretical analyzes suggest that the condition for this type of instability should be controlled by the gas flux and diameter of gas bubbles. This result is published in Earth and Planetary Science Letters.
These experimental results were applied to phenomena in magma chambers such as origin of layred intrusions. The geological implications of the experiments are discussed and are published in Nature and International Journal of Modern Physics.
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Report
(3 results)
Research Products
(16 results)
