O. Spieler

TL;DR: In this article, the authors defined the fragmentation threshold as the minimum pressure differential that leads to complete fragmentation of the pressurized porous rock sample, which is defined as a critical pressure difference between the bubbles and the surrounding magma.

TL;DR: In this article, the authors used a modified shock-tube-based fragmentation bomb to measure the gas permeability of volcanic rocks and found that at low porosity, gas escape occurs predominantly through microcracks or elongated micropores.

TL;DR: In this article, a comprehensive database of combined gas permeability and fragmentation experiments was used to deduce a fragmentation criterion that incorporates gas permeabilities as well as porosity and internal overpressure, which implies that the energy required for fragmentation is less dependent on the actual pore geometry than on the way the void space is interconnected and thus on the contribution of permeable gas flow to decompression.

TL;DR: In this article, a series of rapid decompression experiments on three sets of natural samples from Unzen volcano, Japan were performed by dry sieving for particles larger than 250 μm and wet laser refraction for smaller particles.

TL;DR: In this article, the configuration of the shallow plumbing system was inferred from direct observation of extrusion sites and porosity of erupted products, and the conditions that lead to fragmentation and, ultimately, to explosive eruptions.