Intensity Scale ESI 2007 for Assessing Earthquake Intensities

Earthquake intensity scales were introduced at the end of the nineteenth century (e.g., Rossi-Forel, Cancani, Mercalli) in order to characterize source parameters, damage distribution, and environmental impact of relevant seismic events. These intensity scales were based on a classification of earthquake effects on humans, on buildings, and on the natural environment. Intensity provides a measure of earthquake-induced damage both at a site (local intensity) and at the epicenter (epicentral intensity). It is important to note that intensity evaluations consider the coseismic effects in the whole range of frequencies of vibratory ground motion, together with those resulting from static, finite deformations (fault ground ruptures)

Scoring and Testing Procedures Devoted to Probabilistic Seismic Hazard Assessment

This review addresses long-term (tens of years) seismic ground-motion forecasting (seismic hazard assessment) in the presence of alternative computational models (the so-called epistemic uncertainty affecting hazard estimates). We review the different approaches that have been proposed to manage epistemic uncertainty in the context of probabilistic seismic hazard assessment (PSHA). Ex-ante procedures (based on the combination of expert judgments about inherent characteristics of the PSHA model) and ex-post approaches (based on empirical comparison of model outcomes and observations) should not be considered as mutually exclusive alternatives but can be combined in a coherent Bayesian view. Therefore, we propose a procedure that allows a better exploitation of available PSHA models to obtain comprehensive estimates, which account for both epistemic and aleatory uncertainty. We also discuss the respective roles of empirical ex-post scoring and testing of alternative models concurring in the development of comprehensive hazard maps. In order to show how the proposed procedure may work, we also present a tentative application to the Italian area. In particular, four PSHA models are evaluated ex-post against macroseismic effects actually observed in a large set of Italian municipalities during the time span 1957-2006. This analysis shows that, when the whole Italian area is considered, all the models provide estimates that do not agree with the observations. However, two of them provide results that are compatible with observations, when a subregion of Italy (Apulia Region) is considered. By focusing on this area, we computed a comprehensive hazard curve for a single locality in order to show the feasibility of the proposed procedure

Economic freedom: a comparative study

Economic Freedom, Religion, P500, Z120,

Automated assessment of macroseismic intensity from written sources using the fuzzy sets

We apply a computer-aided methodology to assess macroseismic intensity from the descriptions reported by documentary material available for eight Italian earthquakes occurred around the beginning of the instrumental era. The procedure consists of three phases: (i) the identification of significant macroseismic effects on the sources and their archiving in a georeferenced database, (ii) the association between the effects and the degrees of the intensity scale by the comparison with traditional estimates made by macroseismic experts, (iii) the assessment of intensities using a multi-attribute decision-making algorithm based on the Fuzzy Sets logic. This work represents a substantial improvement of our previous efforts as we completely redesigned the three phases of the procedure in the light of the experience of the last 10 years and analyzed six further Italian earthquakes so that our database now includes more than 19,000 encoded effects. Our formalized procedure allows to tracing all of the steps of intensity assessment process so that to identify discrepancies with respect to the expert evaluations that might be possibly due to mistakes or to the incomplete account of the available information. Hence, this approach may be useful for providing a systematic and reproducible intensity assessment as well as for supporting standard manmade assessments. The database of effects we have built could also be employed for testing the internal consistency of the macroseismic scale as well as for designing an improved macroseismic scale, based on consistent statistical criteria