Earthquake occurrence models in the short and long term for the Italian seismicity

Abstract

This work describes three earthquake occurrence models, two in the short-(24 hour) and one in long-term (5- and 10 year), applied to the whole Italian territory in order to assess the occurrence probability of future (M≥5.0) earthquakes. The first model for short-term forecasts is a purely stochastic Epidemic Type Earthquake Sequence model (ETES). The second short-term epidemic forecast is based on a model physically constrained by the application of Dieterich rate-state constitutive law to the earthquake clustering (ERS). The third forecast is based on a Long Term model that considers the perturbation of earthquake probability for interacting faults by static Coulomb stress changes (LTST). These models have been submitted to the CSEP (Collaboratory for the study of Earthquake Predictability) forecast testing for Italy (ETH-Zurich) and locked down to test their validity on real data in a forward way starting from August 1, 2009.