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ARTICLE IN PRESS
46 L. Ferranti et al. / Quaternary International 145– 146 (2006) 30–54
showing marine deposits with S. bubonius, Cosentino
and Gliozzi (1988) identified the uplift pattern of the
Calabria region (Southern Italy). Uplift rate estimates
by Cosentino and Gliozzi (1988) were, however, of
limited accuracy due to the large correction (+25 m)
applied to account for the unknown palaeo-bathymetry
of the Strombus-bearing deposits. Cosentino and
Gliozzi (1988) proposed that uplift of Calabria resulted
from deep forces originating within or above the slab
subducted beneath the southern Tyrrhenian Sea and
margin (Fig. 5a). Based on a detailed field investigation
of the last interglacial and older terraces in Southern
Italy, Westaway (1993) and Miyauchi et al. (1994)
concluded that the Calabrian sector has experienced
regional uplift since $0.7–1 Ma.
The recent compilation from Bordoni and Valensise
(1998) incorporated a larger number of data (105)
of the MIS 5.5 from southern as well as central Italy.
Based on the altitudes of the MIS 5.5 markers, the
authors identified three different crustal sectors. The
central Italy sector shows a moderate ($20 m ampli-
tude) bulge tapering off along the coast, which they
attribute to the injection of magma in the 420 ka
old volcanic centres of Lazio. A larger amplitude
($150 m) bulge spanning from the hinterland, over the
frontal thrust belt to the foreland was first recognized in
the southern Italy sector. The sector with the largest
uplift (up to 170 m) is located between Sicily and
Calabria, and shows spikes related to local extensional
subsidence in a general uplift context (Bordoni and
Valensise, 1998).
Our compilation of the MIS 5.5 data identifies coastal
sectors where vertical tectonic displacements are con-
sistent with existing models, and refine current estimates
of displacement rates. For the remaining sector of the
Italian coastline (northern Italy and Sardinia), our
analysis provides the first comprehensive overview of
the vertical displacement pattern, which gives new
insights into the current deformation processes.
Fig. 13 shows the average uplift rates occurring along
the entire Italian coastline since the MIS 5.5. We
recognize that the uplift rates are average estimates
since $125 ka, and do not show the temporal variability
that might have occurred at the earthquake cycle scale.
Moreover, tectonic stability, as well as vertical tectonic
displacement must be checked against independent
evidence, which is best provided by the altitude of
younger (i.e. Holocene) markers. However, determina-
tion of Holocene displacement is difficult for most sites
in Italy because of observational limitations imposed by
the small displacement accrued. Thus, the pattern
provided by the MIS 5.5 markers remains for most of
the Italian coastline an unsurpassed proxy for recent
vertical tectonic motion.
Sardinia is tectonically stable with a very slight
subsidence of all but the central part of the eastern side,
where localized uplift prevails (Fig. 13). This reveals a
continental margin approaching a mature and thermally
cooled stadium. However, weak tectonic deformation is
indicated by displacement of the marker. Small differ-
ential subsidence of the southern sites is consistent with
GPS velocities studies (Oldow and Ferranti, 2005), which
indicate modern, aseismic strike-slip deformation across
the Campidano graben (Fig. 7).
A similar situation might occur in NW Sardinia,
where local fault-induced subsidence might explain the
westward down-step of the highstand marker, consistent
with tectonic reconstructions (Casula et al., 2001). On
the eastern side of the island, the local dome outlined by
the MIS 5.5 marker might be related to residual volcanic
injection at shallow depth in an area which experienced
intense but localized Pliocene–Quaternary volcanism
(Assorgia et al., 1997; Casula et al., 2001).
The paucity of data regarding the Liguria coastlines
makes the interpretation of the regional vertical tectonics
problematic. The little information available indicates a
mild uplift with the eastern coast moving at higher rates
than the western coast ($0.02 and $0.2 mm/a, respec-
tively, Fig. 13). This appears consistent with the long-
term geological record, which documents a different
vertical behaviour from east to west, with exhumation of
the Ligurian Alps (western Liguria) at $0.1 mm/a in the
last 5 Ma (Foeken et al., 2003), and Quaternary surface
uplift of the Ligurian Apennines (eastern Liguria) at
$1 mm/a (Bernini and Papani, 2002). This area has
experienced extensional tectonics throughout the Neo-
gene, and extension is still active today as documented by
seismicity (Fig. 5a and b). It is therefore deduced that the
uplift rates in the last 1 million years are similar to those
in the last 100 ka, but further investigations are needed to
fully support this interpretation.
On the eastern coast of Northern Italy vertical
displacements occur in an area of contractional tec-
tonics. This displacement changes along the coast from
weak uplift to strong subsidence (Fig. 13). The low uplift
rates (less than 0.1 mm/a) of the MIS 5.5 marker in the
Marche region are related to low-amplitude folds
growing underneath the coast (Vannoli et al., 2004).
This situation occurs behind the active frontal thrust
and in the hanging-wall of an inner thrust which borders
the mountainous topography of the northern Apennines
(Fig. 8). Further to the north, the subsidence of the
northern Adriatic coast (Fig. 13) at a rate of $1 mm/a
occurs behind the buried frontal thrust, which is
supposed to be active (Benedetti et al., 2000; Burrato
et al., 2003) and in the footwall of the thrust which
forms the chain escarpment (Fig. 8) and is characterized
by contractional earthquakes (Fig. 5b). This subsidence
decreases towards the fronts of the Southern Alps and
Dinarids (Figs. 5b and 13). The subsidence pattern is
consistent with the model of a flexure situated in front of
the seismically active main thrust of the northern