Reconciling Geodynamics and Seismology

Thomas Bodin - Laboratoire de Geologie de Lyon, ENS Lyon (introduction: Helle Pedersen 10:45-11h)

Earth sciences are by essence multidisciplinary as different fields study the same objects and processes at different scales, ranging from the formation of continents to subducting slabs. In seismology, the challenge is that tomographic models constructed from long period seismograms only “sees” the mantle as an effective medium, where the smallest scales are given by the resolution power of seismic waves. On the other hand, geodynamics and geochemistry “see” the Earth mantle as a marble cake mixture of different chemical components, with the smallest scales given by chemical diffusion. In this presentation, I will show how modern tools from inverse theory, computational statistics, and data science can surpass qualitative interpretations of results obtained separately in different fields. Within a Bayesian framework, we will propose a fully probabilistic approach to explore the ensemble of small-scale earth models compatible with a set of observations and constraints.