Volcanic Ballistics: Hazards and Risk Management PDF

*Ballistics comprise fragments of magma and old (i.e., pre-existing) rocks ejected during an explosive eruption at variable velocity and angle on cannon ball-like trajectories; they are not entrained within the volcanic plume and are dispersed in proximity to the vent (typically 5 km) (adapted from...

*Ballistics comprise fragments of magma and old (i.e., pre-existing) rocks ejected during an explosive eruption at variable velocity and angle on cannon ball-like trajectories; they are not entrained within the volcanic plume and are dispersed in proximity to the vent (typically 5 km) (adapted from Biass et al., 2016 and Bonadonna et al., 2021).* Ballistics may be a few centimetres to several metres in diameter. In most cases, the range of ballistics is a few hundred metres to 5 km, but they can be thrown to distances over 10 km in the most powerful explosions (Blong, 1984). Some blocks and bombs (i.e., tephra clasts \>64 mm) can also be entrained within the volcanic plume and sedimented at larger distances than ballistics (Osman et al., 2019). Fragments of all sizes generated during fragmentation of magma and lava are also known as 'pyroclasts' whether they travel through the atmosphere or are directly entrained in lateral moving flows. Various analytical and numerical models have been developed that forecast ballistic dispersal (e.g., Fitzgerald et al., 2014; Biass et al., 2016). Primary hazards. The high kinetic energies of ballistics when they land makes them hazardous to people, buildings, infrastructure and other assets. Ballistics may be ejected at over 300 m/s but slow down during flight, with terminal velocities typically \