Descrizione del progetto
Un nuovo modello per il flusso dei liquidi all’interno della Terra
La trasformazione delle rocce della crosta terrestre durante l’interramento e il riscaldamento produce liquidi che svolgono un ruolo importante per la generazione di terremoti, magmatismo, crescita crostale e cicli geochimici globali. Nonostante i recenti sforzi compiuti, risulta impegnativo riconoscere e quantificare i flussi dei liquidi nelle rocce naturali e dare forma ai percorsi dei liquidi. Il progetto PROMOTING, finanziato dall’UE, esaminerà questi liquidi adoperando nuove simulazioni al computer. I modelli saranno alimentati e arricchiti con dati ottenuti tramite l’impiego di nuove tecniche per immagini ad alta risoluzione per condurre l’analisi delle rocce. Il progetto produrrà inoltre il primo modello informatico per il metamorfismo, integrando la mobilità degli elementi dalla scala della roccia alle sezioni crostali. I modelli esistenti si basano sull’analisi termodinamica di singoli tipi di roccia e non tengono conto dei mutamenti chimici provocati dall’espulsione dei liquidi e dall’interazione con le altre rocce.
Obiettivo
Prograde metamorphism produces large amounts of fluids that have an important role for earthquake generation, arc magmatism, the growth of continental crust and for global geochemical cycles. Despite recent efforts, it remains challenging to recognize and quantify fluid fluxes in natural rocks and to model fluid pathways. The existing petrological modeling techniques are all based on the thermodynamic analysis of single rock types and neglect the chemical changes caused by fluid expulsion and the possible interactions with other rocks. The next frontier in metamorphic petrology is therefore to move our modeling capabilities from an isolated single rock system to an open and multi rock system, in which fluids can flow in, react and flow out. This concept introduces several challenges from the quantification of fluid-rock interactions in natural samples to the integration of aqueous thermodynamics and fluid dynamics in the petrological models. Based on the developments of high-resolution techniques such as quantitative compositional mapping, I have demonstrated that the petrological models can be inverted to quantify prograde metamorphism based on preserved mineral relics that partially re-equilibrated in the presence of fluids. The primary objective of PROMOTING is to develop a brand-new framework for petrological modeling of fluid-rock interactions in different, coupled rock types during prograde metamorphism. The models will be calibrated on two key tectonic settings that shaped Earth: subduction of oceanic crust and differentiation of the continental crust. A cutting-edge petrochronological strategy is required to identify at which conditions and when fluid-rock interactions occurred in natural rocks. The outcomes of this project will not only form the basis for a new generation of models integrating element mobility from rock scale to crustal sections, but they will also bring new constraints to test the validity of the most advanced subduction models.
Campo scientifico
Programma(i)
Argomento(i)
Meccanismo di finanziamento
ERC-STG - Starting GrantIstituzione ospitante
3012 Bern
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