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138 F. Antonioli et al. / Global and Planetary Change 34 (2002) 121–140
San Vito Promontory indicate a mismatch of about 20
cm. If we subtract the 8 cm of living Vermetids, we
obtain a difference of about 10 cm, which lies within
the uncertainty of 14C datation. For Marettimo Island,
the difference between predicted and observed is
about 3.5 m. This result certainly needs further
studies.
Fig. 12 shows that for different time slices sea level larly for what regards the last five centuries. This
data are different, evidencing that sea-level curves
cannot be obtained on a national basis, but only on a
regional one. We suppose this is due to differences in
crustal rebound, since relevant tectonic movements do
not seem to be related to the maximum level of
Tyrrhenian ingression (stage 5e), which is easy to
determine: Argentarola notch 5.30 m s.l.m., Palinuro
notch 2.8 m s.l.m., Marettimo notch 7.8 m s.l.m., San
Vito Lo Capo notches and inner margin from 8 to 13.8
m s.l.m. The difference in sea level can be attributed
to tectonical or hydroisostatic adjustments (i.e. San
Vito Lo Capo), but it seems of little significance when
compared to the ages of Spelothems and Vermetids.
5. Conclusions
The results of the researches carried out along
coastal tracts of the Capo San Vito Promontory and
Marettimo Island underline the positive role of an
interdisciplinary approach in characterizing the
coastal evolution of the sector during the Quaternary
and unravelling the sea level and climate history
occurred in its recent and geological past.
Particularly, the aim of our study was to collect
original data regarding the sea-level rise during the
Holocene. The selection of the site resulted successful
for this purpose, because of its notable morphological
preservation, quite uncommon for the Mediterranean,
although not associated with the conservation of the
original depositional and textural characters of the
Quaternary deposits, probably due to the alternation
of semiarid and semihumid climatic intervals in the
area during the last thousand years (Mauz et al.,
1997).
The crustal uplifting of the whole area allowed a
series of marine terraces and notches of Middle –
Upper Pleistocenic age to remain well preserved.
The accurate mapping of their present-day height
above sea level has been used in order to verify the
differential vertical mobility among different sectors
and to evaluate the maximum displacement and, thus,
the reliability of datable indicators of palaeo-sea
levels.
Vermetid (D. petraeum) reefs and submerged spe-
leothems confirmed to be a tool for reconstructing a
sea-level rise curve for Northwestern Sicily, particu-
represents a new result to be held in consideration
and, possibly, to be used as an input for the improve-
ment of geophysical sea-level models of regional
significance for the Central Mediterranean Sea.
The palaeo-sea level data obtained for Marettimo
Island suggest the presence of a small anomaly with
respect to other Mediterranean and extra-Mediterra-
nean sea-level curves, although this does not represent
an isolated case for the Central Mediterranean. The
complex and interconnected mechanisms of eustatic
sea rise, coastal rebound and tectonic movements are
still poorly understood and certainly underinvesti-
gated in the Central Mediterranean. It would be of
great interest to extend this kind of investigation to the
entire coast of Italy, with the additional aim of
providing indications on possible future scenarios.
Note added in proof
At the end of cap 3 ‘‘Quaternary marine terraces’’,
we have correlated our terrace VII to the oxygen
isotope stage 3. On the basis of very recent publica-
tions on timing and altitude of sea level, now we argue
that the À 18 to À 15 m terrace was carved during
stage 7. In fact, Bard et al. (2002) recently established
that the sea level during stage 7a should be comprised
between À 18 and À 10; moreover, Lambeck et al.
(2002) established that sea level of stage 3 was never
higher than À 50 m.
Acknowledgements
This work has been performed under contract no.
ENV4-CT95-0087 from the Commission of the
European Communities in the framework of the
Environment Programme. We acknowledge Professor
Kurt Lambeck for kindly providing some preliminary
results on predicted sea-level values for the inves-