The Attenuation and Scattering Signature of Fluid Reservoirs and Tectonic Interactions in the Central-Southern Apennines (Italy)

Despite the high detection level of the Italian seismic network and the risk associated with its fault networks, Central-Southern Italy has no unique geophysical model of the crust able to illuminate its complex tectonics. Here, we obtain seismic attenuation and scattering tomography models of this area; both reveal high attenuation and scattering anomalies characterizing the entire Apenninic Chain and related to its East- and West-dipping extensional Quaternary tectonic alignments. Fault-associated fractured zones become preferential ways for circulating and degassing high-attenuation CO2-bearing fluids. A previously undetected fluid source area is a high-attenuation volume below the Matese complex, while a similar smaller anomaly supports a fluid source near L'Aquila. The most prominent low attenuation and scattering volumes reveal a locked aseismic zone corresponding to the Fucino-Morrone-Porrara fault systems, representing a zone of significant seismic hazard.