What happens when a pyroclastic flow enters the water: numerical modelling of an offshore pyroclastic turbidite

Tis work explores whether the dispersal of material as a pyroclastic flow enters the ocean can be modelled as a turbidity current, and hence elucidate the inititaion, propagation and deposition conditions during these poorly understood events. We simulate the main pulse of the 2003 dome collapse at Soufrière Hills, Montserrat, which propagated down the far valley, into the ocean. The extensive dataset includes vibrocore sediment samples of the submarine deposit, high resolution bathymetry (Figure 1), duration estimates from seismometers,and descriptions of the terrestrial portion of flow and deposit.Our work assumes a debris-type flow travelled descended the proximal flank of Montserrat, elutriating the finer frraction which propagated as a turbulent density current across thebasin

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