MIGRATE · MINERAL-SCALE HETEROGENEITY OF GRANITES: A NEW APPROACH INTEGRATING MICROCHEMICAL ANALYSIS AND THERMO-MECHANICAL MODELLING TO DISCLOSE THE THERMOCHEMICAL EVOLUTION OF THE CONTINENTAL CRUST

MINERAL-SCALE HETEROGENEITY OF GRANITES: A NEW APPROACH INTEGRATING MICROCHEMICAL ANALYSIS AND THERMO-MECHANICAL MODELLING TO DISCLOSE THE THERMOCHEMICAL EVOLUTION OF THE CONTINENTAL CRUST

Earth is unique among known terrestrial planets in having a continental crust; i.e. the life-sustaining interface between our planet’s deep interior and surface. The withdrawal of large volumes of granitic magmas from the middle and lower crust and their emplacement at higher structural levels caused the chemical differentiation of the continental crust, with its upper part enriched in incompatible elements that are fundamental for the establishment and maintenance of a habitable planet. The fundamental objective of the MIGRATE project was to establish the timescale and mechanism of heat and mass transfer within the continental crust, determining the physicochemical evolution of upper crustal magma reservoirs. In this frame, three main issues were addressed. The main goal of the project was to get a deeper understanding on the main petrogenetic processes that, controlling the composition of granitic magmas generated by partial melting of crustal rocks, ultimately regulate the composition of the outermost layer of our Planet. The second issue addressed in this project has been the thermal evolution and thermal structure of the continental crust in response to the formation, migration and emplacement of granitic magmas. This topic is the one that has the most immediate impact for society as heat transfer induced by magma ascent and storage in the shallow crust generates transient thermal anomalies that, under specific conditions of water availability and permeability, gives rise to geothermal fields, thus potentially producing cost-effective, renewable energy. MIGRATE targeted non-exposed young granitic rocks associated to the large-scale steam-dominated Larderello-Travale geothermal field in Tuscany (Italy). Today, this field produces ca. 6000 GWh of electricity, corresponding to ca. 2% of the total Italian national demand. Finally, the third goal was to retrieve the long-term thermal history of potentially eruptible magma reservoirs to constrain the physical conditions under which these magmas are retained in the shallow crust. This issue is relevant to get a better understanding on the fundamental processes that control storage and crystallization of magmas at depth vs. volcanic eruptions.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз