«Se dice etiam per teremoti esser sommerso et ruinato tre terre» (How a large historical earthquake was born)

Abstract

There was once a physician (called Andrea Alpago or Maestro Andrea da Belluno, from his NE Italy hometown) who went to work for the Venetian consulate in Damascus around 1487, stayed there up to 1517, learned Arabic and was the first European ever to translate Avicenna’s works from the original (Levi della Vida, 1960). Thanks to his linguistic skills Maestro Andrea became an expert advisor on the political and commercial situation of the entire East (from Egypt and Turkey to Arabia and India) and in particular on the “Signor Sophi” or “Suffi”, i.e. the Shah of Persia Ismā'īl, founder of the Safawid dynasty (1502-1524), whose alliance Venice was then seeking to obtain against the Turks. Between 1504 and 1514, Maestro Andrea sent to the Venetian government many confidential reports, that were copied by Marino Sanudo in his Diarii (De Bertoldi, 1888). In a report dated on 10 March 1514, Mastro Andrea, describes at length the doings of the new Turkish sovereign, Selim I “the Grim”, in Anatolia (he was liquidating all his internal enemies – namely his stepbrothers and nephews - before starting a war against Egypt and Persia). The report ends, as an afterthought, with this piece of information: “Se dice etiam per teremoti esser sommerso e ruinato tre terre del Soltan a li confini del Turcho, videlicet Malathia et Terso et Adena”. This is the earliest, and only contemporary testimony of an earthquake about which very little is known. It must have happened before the letter was written, but was it in late 1513 or early 1514? It heavily damaged (as shown by the verbs “submerged” and “ruined”) at least three towns of SE Anatolia, but it seems curious that two of them - Tarsus and Adana - are close to each other, while the third – Malatya – is more than 300 km away (Fig. 2). What happened in between? Could someone - either Maestro Andrea who wrote by hearsay (“se dice”) or Sanudo who copied him - have made a mistake in trascribing one of these names? Could some other place-name have been wrongly transcribed as “Malatya”? Sanudo copied the information on the earthquake, saving it for future use. It surfaced, with literary flourishes, in a Venetian chronicle of the years 1512-1514 (Barbaro, 16th c.), and after this chronicle was published (1842) in a 19th century geological treatise (Abich, 1882) that in its turn was one of the sources for Calvi (1941). Seismological studies and catalogues then followed in Calvi’s wake, locating the earthquake either generically in “Cilicia” (the region to which Tarsus and Adana belong), or in Malatya, with Io 6 (Ergunay et al., 1967) or 7 (Soysal et al., 1981). Them came Ambraseys (1989), that went back to the somewhat romanced narration provided by Barbaro (16th c.), calculating Mw 7.4 and locating the epicentre not far from Maras, on the Pazarcik segment of the Eastern Anatolian Fault with I=IX (maximum intensity observed… but where?). Subsequent seismological literature on the Eastern Anatolian Fault, both before and since the 2023 earthquake took and still takes the interpretation of the 1513 or 1514 earthquake provided by Ambraseys (1989) as absolute truth: the 1514 earthquake must have been located near Maras, with a M 7 at least and be a most likely predecessor of the February 2023 earthquake. Yet Ambraseys had changed his mind on this account, concluding that “without further details this information is insufficient to indicate the precise date and area over which this earthquake was felt” (Ambraseys, 2009). And, looking back to the original source of information on it, one must surely agree with him. And how many such “large” earthquakes, based on information as poor as this, could be still taken for granted by overconfident geologists and seismologists, only because they happen to fit with some cherished theory?