Magma fragmentation in highly explosive basaltic eruptions induced by rapid crystallization

NanoSIMS results from olivine-hosted melt embayments: Magma ascent rate during explosive basaltic eruptions

Explosive fragmentation criteria and velocities for vesicular magma

a r t i c l e i n f o We present a new criterion for primary fragmentation of natural rock samples in shock-tube experiments, and new formulae for the effective strength of natural rock samples, for the size of primary fragments, and for fragmentation velocities. These formulae and the fragmentation criterion are given in terms of the physical properties of the rock and in terms of experimental...

A theoretical model of the explosive fragmentation of vesicular magma

Recent experimental work has shown that, when a vertical column of rock under large pressure is suddenly depressurized, the column can ‘explode’ in a structured and repeatable way. The observations show that a sequence of horizontal fractures forms from the top down, and the resulting blocks are lifted off and ejected. The blocks can suffer secondary internal fractures. This experiment provides...

Magma decompression rates during explosive eruptions of Kīlauea volcano, Hawaii, recorded by melt embayments

The decompression rate of magma as it ascends during volcanic eruptions is an important but poorly constrained parameter that controls many of the processes that influence eruptive behavior. In this study, we quantify decompression rates for basaltic magmas using volatile diffusion in olivine-hosted melt tubes (embayments) for three contrasting eruptions of Kīlauea volcano, Hawaii. Incomplete e...

Transition between fragmentation and permeable outgassing of low viscosity magmas

Explosive volcanic eruption requires that magma fragments into discrete parcels. Silicic magma can fragment through brittle failure or other processes that depend on the viscoelasticity of the melt. Owing to the low viscosity of basaltic magmas, however, the fragmentation mechanism must be different and will be governed by fluid mechanics alone. We perform a series of decompression experiments ...