Estimate of seismic surface energy from microstructural studies of pseudotachylyte-bearing faults

The total energy budget of an earthquake is one of the great unknowns in geology. From geological, seismological and laboratory evidences it is clear that the total energy of a seismic event is converted into seismic waves together with dissipation processes such as heat, fracture and friction. One of the sinks of seismic energy is the fracture energy required to propagate the fault surface and produce the surrounding damage zone. This thesis aims at estimating this parameter through the analysis of microfracture patterns found in the wall rock of a pseudotachylyte-bearing fault of the Gole Larghe Fault Zone (Adamello massif, Italy). Knowing the magnitude of the surface fracture energy it will be possible to make some considerations on the total energy of a seismic event. Understanding its partitioning is fundamental to also understand the mechanics of earthquakes.