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Development of a coupled model for conduit flow in viscoelastic deformable conduit
No full textThe temporal evolution of volcanic eruptions is controlled by the interaction between an elastic magma chamber that can accumulate overpressure and variable flow resistance of the volcanic conduit. One of the processes that influence changes in the flow resistance is the conduit deformation, which has been studied using the lumped-parameter model to simulate the cyclic or oscillatory behavior during effusive eruptions. However, previous LP models oversimplified the processes during conduit ascent by ignoring changes in the physical properties of the magma. In this study, we proposed a new model coupling the one-dimensional steady conduit flow model with the LP model of a magma-plumbing system with the deformable conduit and clarified its typical behavior by numerical approach. The results showed that the magma permeability scale, phenocryst content, and initial water content change the flow resistance through the effective viscosity and bulk density of the magma, which affects eruptive evolution. The model emphasized the importance of conduit deformation in the oscillatory behavior of the discharge rate and chamber overpressure and revealed that the influence of the physical properties of the magma cannot be ignored in the size of the conduit radius and other factors
軟体性頭足類の初期進化史 [全文の要約]
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