The true colours of the Earth: Multi-data and multi-scale inversion for imaging the physical state of the Earth's interior

Dr. Juan Carlos Afonso, Macquarie U.

16 février 2021

The last 20 years have witnessed an outstanding increase in computing power, data‐fusion techniques, and geophysical/geochemical data acquisition programs worldwide, a trend that is likely to accelerate in the next few decades. These advances now allow the Solid Earth community to pursue massive data‐driven simulations and probabilistic joint inversions for the physical state and geodynamic evolution of the Earth's interior with unprecedented complexity and resolution. In fact, the current state of affairs is such that the boundaries between the fields of geodynamics, geochemistry and inverse geophysical theory, traditionally viewed as separate disciplines, are becoming increasingly blurred and symbiotic. Clearly, Earth models that are simultaneously constrained by multiple and complementary observables are necessary to bring a step change in our understanding of, for example, the nature (i.e., temperature, composition, and architecture) and evolution of the lithosphere, its interaction with the sublithospheric mantle, and the forces driving tectonism and plate motion. In this presentation, I will focus on emerging techniques capable of fusing multiple data sets of different nature (e.g. geochemical, geodetic, geophysical) to obtain thermodynamically-consistent models of the physical state of planetary interiors, with emphasis on the 4D thermochemical structure of the Earth's interior. Such models provide critical information on i) multi-scale processes, such as magmatism/volcanism and lithospheric deformation, and ii) natural hazard management and resource exploration frameworks.