Encoding and computer analysis of macroseismic effects

We propose a method for the encoding and the computer analysis of the macro seismic effects deduced from historical sources allowing the complete forma lization of the process of seismic intensity assessment. In the framework o f historical sismology we make use of a multi-criteria decisions-support al gorithm, based on the theory of the Fuzzy Sers. By analyzing the texts of t he available sources for the 1919 Mugello and 1920 Garfagnana earthquakes, we followed a classification criterion which is independent of any macrosei smic scale: we "disarrange" each sentence reported on the sources into 5 sy ntactic elementary components and represent it by a set of alphanumeric cod es. This allows us to retain the maximum adherence to the original sources and to avoid forced interpretations and losses of information due to the ne ed of fitting a given description to each observed effect. Moreover this sc heme also allows to gather equivalent effects by reassigning them the same code, and to use this new classification in further processing. This proced ure could even be seen as an attempt to define a new macroseismic scale on the basis of a statistical counting of different effects occurrences. (C) 1 999 Elsevier Science Ltd. All rights reserved.