al. 2007b) and geophysical studies (Gottsmann et al. 2007)
highlight the role of gas and aqueous fluid dynamics in
caldera deformation. At Yellowstone, bradyseismic events
typically are linked to magma intrusion (Wicks et al. 2006)
or to upward migration of brines from hot, low-permeability
regions (Dzurisin et al. 1990). Without continuous monitoring
of volatile flux and comparison with geophysical time
series, it remains difficult to verify any particular mechanism
of deformation.