Fig. 11

Cartoon depicting the inferred volcanic conduit system at White Island. Magma is thought to reside at a depth of approximately 1 km depth and provides the source of gas and heat to the shallow hydrothermal system. These are transferred to the surface as a single-phase gas (aquamarine), a two-phase vapor and liquid (tan) and single-phase liquid (blue). The region surrounding the VLP source comprises a ductile low permeability zone (brown) which may intermittently rupture causing high gas discharge and VLP activity. The inset box depicts two potential mechanisms whereby subsurface activity from VLP might be linked to surface activity. Stress transfer might occur almost instantaneously, while mass advection from depth is inherently slower and is dependent on the balance of mass driving and resisting forces