Making the most of the Mogi model: Size matters

Magma movements are almost universally associated with volcanic deformation. The Mogi (1958) and McTigue (1987) models link observed surface displacements to behaviour within inaccessible magmatic plumbing systems. well-used due their computational simplicity ease of application, but both limited by assumptions about the deformation source its embedding domain. Domain assumptions, including elasticity, homogeneity, flat topography, have been previously described corrected for. Whilst recognising limits these models, frequent use in literature requires an objective assessment utility against more sophisticated Finite Element (FE) operational (radius-to-depth ratio, ε) relative merits light field data. Here, we relax assumption a small ε. We simulate using Mogi, FE - latter unrestricted ε validate maximum for which analytical can be applied, compare interpretations data from Kīlauea Volcano, Hawai'i. find that correspond sources range is wider than suggested limits. differences between simulated (forward modelling) estimated parameters (inverse less 5% when < 0.37 (Mogi) or 0.59 (McTigue). Misfits depend on whether radial vertical considered simultaneously independently, values radius depth not only as was assumed previously. There little no difference best-fitting inferred at despite high system geometry, sometimes poor correspondences model results GNSS observations. Our demonstrate applied volcanoes magma reservoir radii depths hitherto supposed, previously-established corrections domain simplifications necessary accurately interpret