Explosive fragmentation of erupting magma

摘要: The magma responsible for explosive volcanic eruptions has both a volatile and an inert phase. Deep in the conduit of active volcano, bubbles nucleate as volatiles exsolve. As rises, grow through depressurization continued exsolution. It is thought that when pressure exceeds overlying material, undergoes rapid transformation from continuous magmatic phase with to gas fragmented pyroclastic material. fragmentation process complex poorly understood. To understand better how transport material coupled exsolution vaporization, we have performed experiments on two-phase system, designed simulate eruption process. We identify new vaporization process, which front propagates downwards mixture liquid particulate suppressing growth nucleated by compressing ahead it. This distinct from, may complement, previously identified mechanisms such non-nucleate induced expanding foam.