Effects of rheology, erosion and temperature on seismicity and tectonics in Agri Valley (Southern Italy).
Lavecchia A., Filippucci M., Stabile T., Serlenga V., Prosser G., Tallarico A.
The Agri Valley is a region where crustal evolution is affected by the interaction of several mechanisms. To model these mechanisms and their evolution, we built up a thermo-rheological numerical model, considering the crust as a visco-plastic body, combining the effects of rheological stratification, inherited weak zones, variations in tectonic regime, surface erosion and fluid presence. Results are in good agreement with the observed topographic elevation, surface heat flow, strain rate and velocity fields and show that the effect of the crustal compression and extension favors the activations of the Monti della Maddalena and East Agri fault systems, both cross-cutting the allochthonous units and the underlying carbonatic platform. Several seismic networks operate in the Agri Valley including the local network INSIEME managed by the CNR (Potenza, Italy). The 1744 earthquakes, recorded in the period 2002--2019, are clustered in two different areas (Pertusillo Lake and Costa Molina 2 reinjection well). Model results, including fluid presence, retrieve two seismogenic areas where the stress exceeds the plasticity threshold, that are in good agreement with the recorded seismicity.