Magma flow instabilities in a volcanic conduit: Implications for long-period seismicity

Softening of aged fluids in start-up flows of dense suspensions

“…The proposed mechanism of pressure perturbation is potentially applicable to not only fluid physics but also natural phenomena. Magma demonstrates an example of pressure perturbations in nature: the multiphase fluid of a volcanic eruption flowing through a conduit (pipe) of a volcano towards a vent [33,34]. The system considered here mirrors a general volcanic system consisting of a magma chamber and a conduit, thus the type of pressure perturbation observed here might be related to volcanic oscillation phenomena.…”

Influence of extrusion rate and magma rheology on the growth of lava domes: Insights from particle-dynamics modeling

“…The time taken by the magma ascending at a flow rate of 0.32 m 3 /s and 8.1 m 3 /s to reach the conduit exit is 128 days and 5 days, respectively. Results obtained from 3-D models of crystal networks suggest that the range for maximum crystal volume fraction beyond which the magma behaves as a brittle solid varies between 0.74 and 0.8 (Saar et al, 2001;Hale, 2007). Observational data suggest that for the extrusion of lava structures at Soufriere Hills Volcano, Montserrat with shear surfaces that exhibit solid-like deformation requires a crystal volume fraction greater than 0.7 (Watts et al, 2002).…”

Explosion swarms at Stromboli volcano: A proxy for nonequilibrium conditions in the shallow plumbing system

“…Occurrence times of the swarms are highlighted (a) by rectangles in case II and (b) by arrows in case III. 2002(case I), 2006-2007(case II), 2010. The first two cases involved volcanic crises with both effusive and explosive phases [Ripepe at al., 2005b;Calvari et al, 2011], whereas the third consisted of only small, short-lasting lava emission (http://www.ct.ingv.it/ -Activity of the Sicilian volcanoes, monthly reports).…”