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Figure 7.2 – Isopach map of the area west of Favignana, showing the thickness of the Pio-
Pleistocene. Favignana is located on the right. Unfortunately no data from the eastern part of
Favignana exists up to date. Note the high thickness north of the island, between Favignana
and Levanzo. The isopach values are in milliseconds, image after D’Angelo et al. (2005).

the edge on the right side of the image is the isopach line of 200 milliseconds just visible, suggesting that
this is the minimum thickness of the Plio-Pleistocene on eastern Favignana.

7.4 Tectonic and eustatic processes

Marine deposits are always subject to changes in sea level, and the active tectonism of Sicily will have
consequences for the uplift in the area. During the fieldwork no investigations of sea level fluctuations
recorded by the Favignana calcarenite was carried out. Similar — somewhat younger — deposits are
however chronostratigraphically evaluated. D’Angelo & Vernuccio (1996) investigated the Middle to
Upper Pleistocene calcarenites on the Sicilian mainland, situated between Trapani and Mazara del
Vallo (see figure A.1 as a reference for the geographical location). These deposits are locally known as
Calcareniti di Marsala — or Marsala calcarenite — which are used as a building material just like the
tufo from Favignana. A number of terraces are distinguished, spanning in elevation from over 100 m
AMSL inland to sea level at the shore. The authors suggest a correlation between the terrace formation
and the Pleistocene sea level chronostratigraphy. The marine isotope correlation chart in figure A.1 shows
this attempt. Terrace age corresponds approximately to periods of high sea level. However, because the
present day sea level is relatively high, a terrace that is currently 100 m AMSL would have been deposited
at a very different elevation. This large difference indicates that tectonic influence must have played an
important role in the region. Similarly, the highest point of the eastern part of the island rises more than
50 m above the present day sea level, indicating that uplift must have been influencing the morphology of
Favignana as well. It is therefore likely that the present Monte Santa Caterina structures resulted from an
uplift phase which is ongoing since at least Pliocene until today as is indicated by frequent earthquakes
of medium magnitude (2.5–3.5 on the Richter scale) that occurred in the area over the last two years.

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