2016 Fiscal Year Final Research Report
Experimental investigation of the effects of suspended crystals on rheology of highly crystalline lavas
Project/Area Number |
25800293
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Research Category |
Grant-in-Aid for Young Scientists (B)
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Allocation Type | Multi-year Fund |
Research Field |
Petrology/Mineralogy/Economic geology
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Research Institution | Shizuoka University |
Principal Investigator |
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Project Period (FY) |
2013-04-01 – 2017-03-31
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Keywords | マグマ / レオロジー / 結晶 / サスペンジョン / 粘性-脆性遷移 / 熔岩流 / 桜島火山 |
Outline of Final Research Achievements |
High-temperature uniaxial compression viscometry was done for highly viscous lavas, including crystal and bubble-free obsidian, bubble-free andesitic lava with 38 vol.% microlites, and three-phase andesitic lava from Sakurajima volcano. Present results suggest that (1) uniaxial compression viscometry is an useful tool to investigate highly viscous, multi-phase lavas, (2) the existing melt-viscosity model of Giordano et al. (2008) is valid, and (3) preferred orientation of plagioclase crystals strongly influences on lava viscosity. In addition, quantitative rheological model is established and shear rate-temperature condition at which viscous-brittle transition occurs is determined for crystal- and bubble-bearing andesitic magma which is representative at Sakurajima volcano. Present results may be helpful for simulating lava flow dynamics of Sakurajima volcano and other andesitic volcanoes.
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Free Research Field |
マグマ科学
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