Understanding the structure of the Earth’s subsurface is fundamentally an inverse problem with sparse direct observations and abundant indirect measurements. Drillholes provide precise but extremely limited information, while geophysical signals such as gravity, magnetics, and seismic data provide broader but indirect constraints on the underlying geology.

In this talk, I introduce the concept of subsurface world models, generative AI systems trained to learn the statistical and physical structure of the Earth from large ensembles of synthetic geological models and geophysical simulations. These models combine sparse hard constraints such as drilling and geochemistry with dense indirect observations from geophysics to infer plausible three-dimensional geological structures while quantifying uncertainty.

Such models offer a new approach to mineral exploration and resource discovery. More broadly, subsurface world models provide a framework for reconstructing hidden planetary interiors from limited observations, with potential applications in geohazard assessment, geothermal exploration, carbon storage, and planetary exploration.

Speaker bio: 

Gerrit Olivier,

Chief Scientific Officer, Fleet Space Technology

Gerrit is a pioneer in using ambient seismic noise-based methods in the mineral and materials exploration industry. During his career, he has developed novel low-impact subsurface monitoring and imaging methods for the mining industry. Gerrit completed his MSc in Theoretical Physics at the University of Stellenbosch (South Africa) and his PhD in Geophysics at the Université Grenoble Alpes (France). He is the holder of numerous awards for his work in passive seismic methods, and is committed to expanding its use for mineral exploration on Earth and beyond.

Gerrit is a former Director and Head of Applied Geophysics at the Institute of Mine Seismology, and current Senior Adjunct Researcher at the Centre for Ore Deposits and Earth Sciences at the University of Tasmania and Adjunct Associate Professor at the School of Science and Engineering at the University of Sunshine Coast.

Gerrit is leading the Fleet Space team that aims to deploy a geophysical device on the dark side of the Moon by 2026 that will improve our understanding of its interior composition and formation.

*Coffee and Snacks will be provided.