The effects of volatiles in destabilizing stratified magma chambers are studied with numerical simulations. The system under investigation is a 2D magma chamber hosting a chemically and thermally stratified magma. Numerical simulations have been carried out by using a newly developed finite element code for the transient multicomponent dynamics of compressible and incompressible homogeneous flows of volcanological interest. This code represents an extension of the highly stable and accurate algorithm developed by Hauke and Hughes (1998). The magma properties depend on local conditions in terms of pressure, temperature, and composition, and Newtonian rheology is assumed. Volatiles include water and carbon dioxide in variable proportions and in chemical equilibrium with the multicomponent liquid. Parametric studies have been carried out on the initial volatiles distribution, magma composition and temperature, and chamber location, size, and geometry. Computational results allow to define conditions required for the gravitational destabilization of magma within the chamber. They also show the time-space distribution of chamber pressure, temperature, velocity, and composition, as well as the patterns of convective motions and volatiles exsolution.
Numerical investigation of destabilization and overturning in volatile-rich magma chambers
BARSANTI, MICHELE;
2004-01-01
Abstract
The effects of volatiles in destabilizing stratified magma chambers are studied with numerical simulations. The system under investigation is a 2D magma chamber hosting a chemically and thermally stratified magma. Numerical simulations have been carried out by using a newly developed finite element code for the transient multicomponent dynamics of compressible and incompressible homogeneous flows of volcanological interest. This code represents an extension of the highly stable and accurate algorithm developed by Hauke and Hughes (1998). The magma properties depend on local conditions in terms of pressure, temperature, and composition, and Newtonian rheology is assumed. Volatiles include water and carbon dioxide in variable proportions and in chemical equilibrium with the multicomponent liquid. Parametric studies have been carried out on the initial volatiles distribution, magma composition and temperature, and chamber location, size, and geometry. Computational results allow to define conditions required for the gravitational destabilization of magma within the chamber. They also show the time-space distribution of chamber pressure, temperature, velocity, and composition, as well as the patterns of convective motions and volatiles exsolution.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
