GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 1.1 GNGTS 2024 One Earthquake, Two Scenarios: The Bafing Case of the 1467 Siena Earthquake. A. Arrighet 1 , B. Gelli 2 , V. Castelli 3 1 École normale supérieure - Université PSL (AOROC UMR 8546), Paris, France ; 2 Università degli Studi di Siena, Italia; 3 INGV, Bologna/Ancona, Italia Historical seismology is a work in progress: the overall picture of a given historical earthquake, no mater how long taken for granted, can sometmes change, either thanks to the discovery of “new” (i.e. previously unknown or unheeded) historical sources, or by considering the research output of other disciplines. Historical seismologists tend to give precedence in their studies to writen evidence, derived (when a choice is possible) from the sources 1) most likely to provide informaton useful to fulfll their main objectves (i.e. assessing macroseismic data points, reconstructng macroseismic felds and damage scenarios), and 2) not requiring long-drawn out, possibly unsuccessful searches that would hardly ft with their generally tght deadlines. Unavoidably, this approach mean to discard interestng but elusive evidence, whose records are buried too deep to make a search cost- efectve, or were never writen down at all but survive as the marks which past earthquakes lef on buildings. It is up to the scholar to fnd ways and means to interpret these unwriten records, even if the readings taken are not always conclusive. The archaeoseismological study of historic towns and buildings allows to gain in-depth knowledge of how a given earthquake interacted with architectures and building components and in some cases, it can also provide evidence of the social, economic, or even politcal consequences of some earthquakes. The project PROTECT – Knowledge for PReventON - Technique s for repairing seismic damage from the medieval period to the modern era (fnanced by the European Union’s Horizon 2020 research and innovaton program together with a Marie Skłodowska-Curie Individual Fellowship) applies, on an entrely experimental basis, the methods of archaeoseismological analysis to the historic centre of Siena (Tuscany), to improve the knowledge of its context for purposes of seismic risk reducton. By weaving together the informaton gathered by diferent humanistc and scientfc disciplines, the PROTECT project aims to defne an operatonal protocol for the archaeoseismological reading of the historic centre of Siena (or part of it). This protocol could be exported to other Italian/European towns, with a view to improve our understanding of their historic heritage and the best ways to protect it from seismic risk. The PROTECT project started in December 2021 with a frst step aimed at a general analysis of the historic city centre with reference to a specifc earthquake. Afer an inital look at the seismic history of Siena, the choice fell on the August-September 1467 seismic sequence (Fig. 1).