WP2 - Physics of short term seismic changes and its use for large earthquakes predictability
WP Leader: Bernard Pascal - CNRS

The objectives are:
- To improve short-term forecasting of large earthquakes through the integration, in a quantitative manner and with a probabilistic approach, of time-dependent information provided by the monitoring of the seismic and strain activity within specific fault systems at 4 selected sites. The selected sites are four seismically active areas representative of different seismo-tectonic contexts the study of which is already benefiting from dense instrumentation: Corinth (Greece), Marmara Sea (Turkey), Irpinia (Italy), and Valais (Switzerland). In particular, we make use of data-constrained physical models of the mechanical processes involved in order to identify possible types of observations that may significantly improve short-term earthquake forecasting capability.
- To improve forecasts by the quantification of the basic parameters of the forcing strain transients (location, geometry, amplitude). The detection of fluid signatures in the transient may potentially help to better constrain the physical processes at work.
- To detect changes, not only of the clustering properties of seismic activity, but also of other seismic source parameters, in the properties of the surrounding medium and of stress/strain around the seismic sources.
- To investigate the coupling of seismic and aseismic transients. This approach will improve our knowledge of the interactions between faults. Indeed, the rupture of small asperities due to transient fault slip is a particular case of fault interaction. Our approach is more general, as it considers not only fault interaction, but also the influence of fluids on the faults (fluid-fault interaction), causing stress changes through pore pressure variations.

Structure of the WP
Task 2.1: Instrumentation
Task 2.2: Observations and analysis
Task 2.3: Modelling