Sviluppo e Applicazione di innovativi metodi di previsione sismica in Italia e Taiwan

Responsabili di progetto

Luciano Telesca, Chien-chih Chen

Accordo

TAIWAN - NSTC - National Science and Technology Council

Bando

CNR/MoST biennio 2018-2019 2018-2019

Dipartimento

Scienze del sistema terra e tecnologie per l'ambiente

Area tematica

Scienze del sistema Terra e tecnologie per l'ambiente

Stato del progetto

Nuovo

Proposta di ricerca

Since the installation of dense seismic networks made available a huge amount of instrumental seismic data, investigating the statistical properties of earthquakes has become challenging to understand the mechanisms of their generation and possible forecasting. Research on earthquake forecasting in the last few decades has increased our comprehension of earthquake process and led to several methods for producing useful estimates of seismic hazard. Since seismicity was identied as an example of natural nonlinear system for which the distribution of event size follows the Gutenberg-Richter (GR) law, the parameters of the GR law (b-value and a-value) and the completeness magnitude have been used in numerous studies focusing on seismic hazard, earthquake forecasting models, and other related topics. However, seismicity is extremely complex phenomenon, thus more sophisticated and robust statistical methods are necessary to be developed and applied to get forecasting schemes that can be possibly used in operational procedures more efficiently than how has been done so far. Thus, the project intends to integrate several forecasting methods and evaluate retrospectively their performance in two highly seismic countries, Italy and Taiwan, comparing the observed seismicity with the parameter space-time patterns paying attention to the occurrence of intense earthquakes. This represents a research priority for both countries, due to the great socio-cultural-economic impact the occurrence of potentially damaging earthquakes could have in territories highly densely populated (like Taiwan) or with numerous historical buildings/cities that even a medium intensity earthquake could irreversibly damage or destroy (like Italy). The project will be implemented by developing and applying several methodologies to accomplish the project's objectives. The Epidemic-Type-Aftershock-Sequences model (Kawamura and Chen, 2013), identifying seismic activation zones before the occurrence of large shocks, the Pattern Informatics method, estimating seismic intensity change (Chang et al., 2016), and the ZMAP method (Kawamura et al., 2014), creating an image of the significance of seismicity rate changes in space and time before large earthquakes, will be employed to reveal space-time windows where more likely large shocks would occur. These three methods were already successfully applied by the Taiwanese team to identify precursory signs in space-time dynamics in some Taiwanese areas before strong events, but were never used to forecast large events in Italy. In this project, thus, these methods will be tested on Italian territory that has different seismo-tectonic settings. On the other side, the Italian team gained great experience in seismic time series analysis, and more recently in applying the Visibility Graph (VG) method that defines earthquake networks. The VG method is based on a connectivity law between events, discriminating between large events that act as "hubs" and events with lower magnitude, like aftershocks, foreshocks, swarms. The Italian team have already got important results applying the VG in modeling earthquakes occurred in Italy and Mexico (Telesca et al., 2012; Telesca et al., 2013). One of these is the relationship between the connectivity degree and the b-value of the Gutenberg-Richter law (Telesca et al., 2014; Telesca and Toth, 2014). Moreover, the VG-based parameters (the k-M slope defining the relationship between connectivity degree of an earthquake and its magnitude (Telesca et al., 2015), and the mean interval connectivity time (Telesca et al., 2016)) have revealed their potential in forecasting the large earthquake occurred in 2006 in Kachchh (India). In this project for the first time, the forecasting performance of the VG will be tested in Taiwan, a natural laboratory where large events occur frequently. Besides these innovative forecasting methods, the investigation of the statistical properties of seismicity in both countries will be performed to better understand the space-time dynamics of earthquake processes. The results of the project will have important societal impact: the availability of robust forecasting tools could integrate traditional seismic hazard tools that are mainly based on estimating the GR parameters and completeness magnitude. They could help civil protection actions contributing to select those areas where more necessary are risk reduction interventions and improving emergency preparedness. The patterns selected by applying such innovative forecasting methods as the more effective, could be proposed for a forward testing in the next years and in areas more prone to large events in the next future. This project will have also a great scientific impact on seismological modeling: so far the application of robust and innovative forecasting tools was carried out only sporadically on some specific areas; while, the assessment of more appropriate space-time models of seismic processes will prompt their usage in many other seismic areas worldwide. The results will be disseminated through intermediate and final reports, international conferences and ISI papers. The activity of the project will be reported on appropriate website to share the results with the scientific community. This project entails a joint research effort among experts from the two teams: the Taiwanese team has an outstanding experience in seismic investigation of Taiwan and development of forecasting tools; the Italian one complements with a longstanding activity in earthquake analysis and skill in development of geophysical time series analysis. Such synergy is fundamental to attain the aimed goals of the project, and to envisage their cooperation for future project submissions. The outcomes of this project (papers, knowledge transfer, staff mobility, exchange of methods and human resources) will open new avenues in the Taiwanese-Italian cooperation in the context of seismic hazard.

Obiettivi della ricerca

The objectives of the project are: 1) to develop and apply robust forecasting methods to Italy and Taiwan, in order to evaluate the performance of forecasting of intense earthquakes; 2) to improve the understanding of space-time dynamics of seismic process in Italy and Taiwan by using innovative time series based forecasting methods; 3) to evaluate likelihood of claimed relationships between space-time patterns of the parameters calculated by using robust forecasting methods and impending earthquakes; 4) to produce forecasting maps in Italy and Taiwan on the base of the application of innovative forecasting tools; 5) to foster young researchers and Ph.D students of both involved institutions in the project performance through the interaction of the members of both teams; 6) to disseminate intermediate and final results through papers submitted to peer-reviewed journals with IF and conferences and by a dedicated internet website in order to give the maximal visibility to the project.

Ultimo aggiornamento: 12/06/2025