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by the study of a single earthquake. For the 7-year time span here considered, the
newly available primary sources allowed us to fill in some of the gaps that were
revealed by the investigation of the documents written by the Venetian governors,
so that this study provides a sufficiently reliable knowledge of the seismic activity
in the Ionian Islands for the period 1658-1664, as it is briefly summarised in the
following.
After having put the earthquake records in a comprehensive time-space con-
text, it has been possible (i) to define the correct day and month when the 1658
and 1660 earthquakes happened, and (ii) to move the “1664” event back to 1662,
and definitely excluding that the coeval records could report and refer to two dif-
ferent earthquakes. The correct date is an important parameter also in the case
of earthquakes imperfectly known to the parametric earthquake catalogues; from
now on the chances of retrieving information from the mainland and from the far
field area increase, as well as decreases the risk of overestimating the earthquake
size through a wrong combination of effects, in fact related to different earth-
quakes.
The information concerning the 1661 seismic activity in the area, especially in
Zakynthos, was unknown to parametric earthquake catalogues. This is a piece of
information that contributes in completing the list of the earthquakes known to have
affected this area in the past. This systematic research supplemented us also with
the reliable information that no earthquakes at all affected the island of Kerkyra in
this period.
A strong limit still influencing the studies on the earthquakes in the Ionian Islands
lies in the fact that the observers focus their reports mostly on the islands; there still
remains a disturbing silence from the mainland, silence that has to be interpreted in
terms both of the few easily available (and useful) sources and of the uneven interest
shown by Venetian observers toward their neighbours.
For these reasons, at this stage, authors prefer to refrain from proposing macro-
seismic intensities and epicentral parameters. The quite complete absence of infor-
mation on far field effects means for us that data are not enough to be processed, to
obtain and yield reliable magnitude values. To conclude with a suggestion, it seems
to us that one of the more promising ways the collected data could be used is to
compare them with the data on the 20 th
century earthquakes.
Acknowledgments If Jean Vogt were still with us, he would have surely agreed with me in ac-
knowledging the many people who contributed to this paper.
Jean Vogt's brother, Henri (Universite Louis Pasteur, 3 rue de l'Argonne, 67083 Strasbourg
Cedex, France), is gratefully acknowledged for making the consultation and reading of the von
Degenfeld's manuscript possible: this task would not have been accomplished without his help and
patience.
Special thanks go to Massimiliano Stucchi, Vicki Kouskouna and Jean Bonnin, for their keen
reviews and suggestions; to Christa Hammerl, who helped out with the difficulties in translation
from 17th century German; to Michela Dal Borgo, Archivio di Stato di Venezia , for suggestions in
handling and reading the documents; to Paola Migliavacca, Andrea Rovida and Ruben Tatevossian,
for figures and text editing.
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