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ARTICLE IN PRESS
48 L. Ferranti et al. / Quaternary International 145– 146 (2006) 30–54
coastal sector as suggested by offshore well breakouts
(Amato and Montone, 1997) and offset of the sea-floor
(Mariani and Prato, 1992). In this area, regional
Quaternary uplift ended probably during the late
Pleistocene (e.g. Brancaccio et al., 1991; Cinque et al.,
1993) and, thus, the MIS 5.5 marker was in situ before
final tectonic submergence into the Tyrrhenian Sea
(Ferranti and Oldow, 2005b).
Minor uplift of promontories and, locally, coastal
plains in the eastern Tyrrhenian coast is attributed either
to flexural unload at the footwall of normal faults (e.g.
southern border of Versilia plain at $0.1 mm/a, Figs. 9
and 13), or to volcano-tectonic deformation (central sector
of Lazio at $0.25 mm/a; Figs. 9 and 13). Subsidence of the
plains results from hanging-wall displacements at the
bordering faults (e.g. Versilia and Pontina-Fondi plains
subsidence at $0.3 and 0.1 mm/a, respectively, Figs. 8, 9
and 13) or severe volcano-tectonic collapse possibly
triggered by fissural eruptions (e.g. Volturno-Sarno plain
subsidence at $0.5, Figs. 10 and 13).
Today, these processes probably stopped at the
northern-central Tyrrhenian Sea coasts. In the Versilia
plain (Fig. 8) the Holocene marker is not displaced (Nisi
et al., 2003), and the modern tidal notch at the
promontories in Tuscany and Lazio indicates a stable
relative sea-level during the Holocene (Antonioli et al.,
1999b, c). In Lazio, significant volcanic activity ended by
$20 ka (Barberi et al., 1994). Likewise the Holocene
marker is not displaced in the subsiding Campania
plains, and, thus, stability has been attained.
Along the southern Tyrrhenian Sea, however, displace-
ment of the MIS 5.5 marker continues today. The
transition from stable tectonic conditions or local
subsidence to regional uplift probably occurs in central
Campania, indicated by the small uplift of the Sele plain at attained by the displaced markers might indicate a
$0.1 mm/a (Figs. 10 and 13). The slow uplift rates of
southern Campania and Basilicata point to a uplift pattern
observed further south in Calabria (Figs. 11 and 13).
Since the middle Pleistocene Calabria and eastern
Sicily have been subject to relatively high uplift rates.
Continuous uplift is documented by flights of marine
terraces (Dumas et al., 1982, 1987b; Westaway, 1993;
Miyauchi et al., 1994). Uplift rates documented by the
MIS 5.5 marker increase towards the Messina Strait
between Sicily and Calabria and towards central eastern
Sicily (Fig. 13). The maximum uplift rate is identified in
the Messina Straits and at the east Sicily coast where it
might be centred at the Etna volcano (Fig. 11), where a
volcano-tectonic component (Monaco et al., 2002) adds
to the regional deformation. Recent investigation of
the Holocene shorelines in the area indicate that uplift
rates increased from the late Pleistocene to the late
Holocene of $65–125% (Antonioli et al., in press),
possibly as a result of Holocene clustering of fault
displacement superposed on a steady regional uplift
(Ferranti et al., in preparation).
The geometry and dimension of the uplift pattern in
southern Calabria and northeast Sicily points to a
mechanism situated deep in the crust. Uplift of Calabria
is viewed as an isostatic response to slab break-off
(Westaway, 1993; Wortel and Spakman, 2000), or due to
a dynamic support from the asthenosphere wedge
beneath the Calabria–NE-Sicily forearc, which is
decoupled from the subducting plate (Gvirtzman and
Nur, 2001; D’Agostino and Selvaggi, 2004). However,
the area uplifted (Fig. 14) is larger than the area
covering the subducted slab as revealed by tomography
and deep earthquakes (Fig. 5a), as it includes the Jonian
coasts of Basilicata. This latter coastline crosses the
front of the southern Apennines thrust belt and the
foredeep basin. The pattern that the MIS 5.5 terrace
describes is of bulging and tilting of the coast to the
northeast. The basin and frontal belt subsided through-
out the Pliocene–early Pleistocene, but experienced
uplift since the middle Pleistocene (Cinque et al., 1993;
Westaway, 1993; Amato, 2000) together with the
Murge-Salento block (Ferranti and Oldow, 2005a, b)
in Puglia (Fig. 12). This pattern continued after the last
interglacial with an uplift rate of $1 mm/a. Bulging and
tilting of the MIS 5.5 terrace occurred across the thrust
front of the southern Apennines, whose activity ceased
in the early Pleistocene (Patacca and Scandone, 2001).
Thus, displacement of the MIS 5.5 markers in the
Jonian bulge is not indicative of motion of the frontal
thrust, but is consistent with contraction stepped at
deeper crustal levels and involving the whole eastern
part of southern Italy, as documented by GPS velocities
and earthquakes offshore Puglia (Fig. 5b; Ferranti and
Oldow, 2005a, b). In Puglia, the altitude distribution of
the MIS 5.5 marker documents moderate elevation
($25–37 m a.s.l.) of relatively small coastal sectors,
which alternate with sectors where the marker is close to
the eustatic datum. The consistently low elevation
prevailing regional control on vertical displacement,
particularly for the Taranto area which lies at the
northeastern tip of the Jonian bulge. Deep-seated, large-
wavelength folds affect the Puglia structural block
during the Quaternary (Bertotti et al., 2001) and might
be reflected by the low-amplitude bulges indicated
by peaks in the marker’s altitude on the Adriatic coast
of Puglia.
The displacement of MIS 5.5 markers in Sicily, west
and south of the regional bulge, reveal active tectonic
processes. In western Sicily and Ustica Island, small
uplift rates ($0.1–0.2 mm/a) of the marker point to on-
land encroachment of the active contractional belt
detected by seismicity and GPS velocities (Fig. 5b;
Oldow and Ferranti, 2005). The occurrence of limited
areas affected by subsidence probably results from local
components of strike-slip deformation, documented in
several sites along the Tyrrhenian coast of northern