Ricerc@Sapienza

Circulation of fluids in faults controls precipitation of minerals, which can also be of economic interest. The interaction between circulating fluids and host rock may also affect the mechanical properties of faults by processes of dissolution and precipitation. Fluid-rock interaction processes thus produce local variation of fault rock mineralogy that may control reactivation of faults. Previous studies demonstrate that the permeability of fault zones varies depending on the distribution of impermeable fault cores and fractures. However, a full comprehension on how mineralizations (and hence fluids) are distributed at multiple scales of observation and the relationship between their distribution and the internal structure of the fault zone is still lacking. The proposed research project aims at contributing on this topic through a multi-technique and multi-scale approach on various fault zones in the central and northern Apennines. The km-scale geometry of fault zones and characterization of mineralizations will be accomplished by fieldwork. The outcrop scale (10m-1km) distribution of fluids within fault zones will be investigated at centimetric to metric resolution through structure-from-motion multi-view stereophotogrammetry coupled with the collection of structural data on the field and mineral composition of fault rocks and veins. The study of mineralogy of veins associated with faults and fault rocks will be used to reconstruct the geochemistry of paleofluids that circulated and reacted with the host rock. This combined structural-geochemical approach will provide crucial information on the structural control on the distribution of mineralizations, and hence on the physico-chemical properties of the circulating fluids. Preliminary data and our expertise in the topics and techniques that we will adopt make us confident for the completion of the research project.