DFENS: Diffusion Chronometry Using Finite Elements and Nested Sampling

In order to reconcile petrological and geophysical observations of magmatic processes in the temporal domain, uncertainties diffusion timescales need be rigorously assessed. Here, we present a new chronometry method: Diffusion using Finite Elements Nested Sampling (DFENS). This method combines finite element numerical model with nested sampling Bayesian inversion, meaning that parameters contributing timescale estimates can obtained from multiple elements used better constrain individual timescales. Uncertainties associated reduced by accounting for covariance uncertainty structure rather than assuming they are independent each other. We applied DFENS products Skuggafjöll eruption Bárðarbunga volcanic system Iceland, which contains zoned macrocrysts olivine plagioclase record shared history. Olivine provide consistent pre-eruptive mixing mush disaggregation less 1 year. The goes some way toward improving our ability address timescales, but efforts still made understand other systematic sources such as crystal morphology, appropriate choice coefficients, initial conditions, growth, context