Emma Sarrette

PhD Thesis (2026-2029)

Title :Three-dimensional joint modelling of geological structures and hydrothermal features

Supervisors : CAUMON Guillaume (GeoRessources, Université de Lorraine) - COLLON Pauline  (GeoRessources, Université de Lorraine)

The circulation of hydrothermal subsurface fluids over geological time scales involves complex mineralogical, chemical and physical transformations of the rocks. Predicting the intensity of these transformations in space consistently with subsurface data is very important for the exploration and for the effective and safe exploitation of natural resources connected to hydrothermal processes (e.g., ore deposits, geothermal, dolomitization, etc.). 

Recently, an innovative conceptual and numerical model combining structural skeleton and pseudo-distance thresholding was proposed to produce scenarios that jointly forecast the geometry of hydrothermal features and of the associated geological structures (Marchal, Caumon, Collon, Antoine et al., 2024). The first applications in two dimensions have shown the value of the approach to not only interpolate between observations, but also to produce quantitative geological explanations and the associated uncertainties. The goal of this PhD project is to extend this model to three dimensions and to test its value on real data. Beyond the concern for efficiently adapting the method in three dimensions, the main questions to be addressed concern the adaptation of the skeleton simulation to reflect expert knowledge, the consideration of pseudo-distance computation parameters in the inference problem, the consideration of poly-phased alteration phases.