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176 M. Vacchi et al. / Earth-Science Reviews 155 (2016) 172–197
2.2. Database subdivision northern Corsica (Fig. 2). GPS-derived vertical velocities indicate zero
to weakly positive on-going vertical motion in the three regions
To account for the spatial variability of RSL changes we divided the (Fig. 2). The north-central Latium region (#9) stretches from Civitavec-
database into 22 regions (Figs. 1 and 2) on the basis of (1) geographical chia to the Tiber Delta (Figs. 1, 2). In this region, GPS-derived vertical ve-
position, (2) proximity to other RSL data-points (commonly a function locities range from zero to less than 1 mm a −1 while stability to
of local geomorphology, such as coastal plains between headlands, moderate uplift (≤0.23 mm a −1 ) is documented since the last intergla-
(Engelhart et al., 2015), and (3) the regional neotectonic setting derived cial. On the Tiber Delta, long-term uplift of ~0.11 mm a −1 is reported.
from the elevation of the last interglacial shoreline (MIS 5e, data from The southern Italian coast presents a very complex tectonic setting
Ferranti et al., 2006, 2010; Pedoja et al., 2014, if not otherwise specified, (Fig. 2, Ferranti et al., 2010; Faccenna et al., 2014). The Gulf of Gaeta re-
Fig. 2) and, secondarily, from the ongoing GPS-derived vertical veloci- gion (#10) stretches from the Fondi to the Volturno coastal plains and
ties (data from Serpelloni et al. (2013), Fig. 2). includes the Pontine Archipelago (Fig. 2). 0.3 to 0.2 mm a −1 of subsi-
Probabilistic assessment suggests that sea-level elevation during the dence is reported on the Volturno plain during the last ~40 ky BP.
last interglacial (~125 ka ago) was ~7.2 m above the present MSL (Kopp GPS-derived vertical velocities indicate a predominant on-going subsi-
2
et al., 2009). In Fig. 2, the dark and pale green boxes (50 km squares) dence across the area, with greater rates in the volcanic district of the
show the average elevation of the MIS 5e shoreline (as reported by Gulf of Naples (−8mma −1 , Fig. 2) where we avoided the RSL recon-
Ferranti et al., 2006; Pedoja et al., 2014). Dark green boxes indicate av- struction. In fact, it would be not indicative of the general RSL trend be-
erage elevation of between 7.5 and 15 m (stable to very minor uplift) cause this area is strongly affected by significant non-eruptive crustal
while pale green indicates elevation between 0 and 7.5 m (stable to deformation (Morhange et al., 2006). Salerno Bay (#11) includes the
very minor subsidence). These regions can be considered as being coastal plains of Sele River and is located south of the volcanic district
affected by a long-term vertical movement of between −0.06 and of the Gulf of Naples. The several MIS-5e shorelines found in the area in-
+0.06 mm a −1 , averaged for the last ~125 ka. It is worth highlighting dicate average long-term uplift ≤0.06 mm a −1 and no nearby GPS-
that such vertical rates include both tectonics and the GIA signal derived vertical velocities are available.
(Dutton and Lambeck, 2012), and that uplift/subsidence rates are prob- We have avoided RSL reconstructions from the tectonically-active
ably not linear over the last 125 Ka. Calabrian arc, (Fig. 2) which has been affected by significant tectonic up-
In order to better understand the current vertical movements, we lift since the last interglacial (Dumas et al., 2005; Ferranti et al., 2006,
also analyzed ongoing vertical movements recorded by GPS. Discrepan- 2007). The highest rates of uplift are reported near Capo Vaticano (0.6
cies between long-term vertical velocities and GPS measurements were to 2 mm a −1 Tortorici et al., 2003; Ferranti et al., 2010)andin the Mes-
elucidated for some regions. Western Mediterranean GPS trends are sina Straits (~1.0–1.4 mm a −1 ) between Calabria and Sicily (Fig. 2). This
based on short records (often less than 15 years, Serpelloni et al., uplift pattern is related to the interplay between regional and local (i.e.
2013). Thus, they can give insights into the on-going vertical move- fault related) components of vertical displacement (e.g., Ferranti et al.,
ments but are less representative of the general vertical trend of a 2007; Scicchitano et al., 2011); rates of uplift decrease progressively
given region with respect to the MIS 5e elevation. For this reason, we southwards and westwards of the Messina Strait (Ferranti et al.,
primarily used the long-term vertical velocities provided by the eleva- 2010). We have subdivided the coasts of Sicily and Malta into three re-
tion of the last interglacial shoreline for the subdivision of our database gions (Figs. 1, 2). The northwestern Sicily region (#12) stretches from
We subdivided the Spanish Mediterranean coast into two regions Palermo to Marsala, including Marettimo Island. The region shows on-
(Figs. 1 and 2). Central Spain (#1) extends between Alicante and the going vertical movements ≤0.4 mm a −1 and is considered to have
Gulf of Valencia and represents the westernmost region in our database. been tectonically stable since the last interglacial. The mid-eastern Sicily
In this area, historical seismicity is reported (Olivera et al., 1992). GPS region (#13) stretches from Catania to Syracuse. In this area, long-term
vertical velocities document a general subsidence trend with rates uplift rates range between 0.4 and 0.7 mm a −1 (Dutton et al., 2009;
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lower than 2 mm a in this region, notably in the Gulf of Valencia. The Spampinato et al., 2011) and GPS data indicate on-going uplift
northern Spanish coast (#2) extends from the Ebro Delta to Cap Creus, ≤1mma −1 decreasing southwards. In this area, large earthquakes
at the border with France (Fig. 2). GPS-derived vertical velocities indi- and associated tsunamis have been recorded since historical times
cate zero vertical motion in most of the regions, with the exception of (Scicchitano et al., 2007; De Martini et al., 2010).
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the Ebro and Llobregat deltas that show subsidence of 1.5 mm a . Even if they are separated by about 100 km of sea, we grouped the
The central French coast extends from Cape d'Agde to Port Cros southernmost part of Sicily and the Maltese Islands into a single region
Island, including the Rhone Delta. GPS-derived vertical velocities sug- (#14). These two sectors present zero to minimal ongoing vertical
gest zero ongoing vertical motion. The elevation of MIS 5e shorelines movement (Fig. 2) and very weak historical seismicity is reported for
denotes a long-term stability of the area (Ambert, 1999). the area. The relatively shallow (≤−200 m) Malta Plateau presently di-
We subdivided the northern coast of the Ligurian Sea into two vides these two coastal sectors, which were probably connected during
regions (Figs. 1 and 2). The western Ligurian Sea (#4) encompasses the LGM (Micallef et al., 2013). Pedley (2011) reported the long-term
the coastline between Frejus (France) and Genoa (Italy). Nonetheless, tectonic stability of the Maltese Islands.
although both MIS 5e and GPS-derived velocity fields indicate negligible The southern Tunisia region (#15) represents the southernmost
vertical movement across the whole area (Fig. 2), Dubar et al. (2008) area of our database (Figs. 1 and 2). No significant historical seismicity
documented a mild uplift (up to 0.06 mm a −1 ) around the over- is reported in the region and several studies have underlined the tecton-
thrusting Nice Range on the basis of the local MIS 5e elevation. ic stability of southeastern Tunisia since the MIS 5e (Fig. 2, Jedoui et al.,
The eastern Ligurian sea region (#5) stretches from La Spezia to the 1998).
Arno river coastal plain (Fig. 2). Both GPS and long-term vertical veloc- We subdivided the northern Adriatic Sea into three regions (Figs. 1
ities indicate a general subsidence trend of this region, with rates of up and 2). The lagoons of Venice and Friuli, (#16) stretch from the town
to ~0.26 mm a −1 on the Versilia coastal plain. of Venice to the town of Monfalcone including three large coastal la-
Corsica and Sardinia show a general tectonic stability since the last goons (Venice, Caorle and Grado-Marano); a long-term subsidence
interglacial (Ferranti et al., 2006; Fig. 2). They occupy the central sector trend, ranging between 0.7 and 0.4 mm a −1 (Carminati et al., 2003;
of the western Mediterranean, and they were subdivided into the fol- Amorosi et al., 2008b), is reported in this region. GPS-derived data
lowing three regions, northern Corsica and Pianosa, (#6), southern also indicate a subsidence trend with rates higher than 2.5 mm a −1
Corsica-Northern Sardinia (#7) and southwestern Sardinia (#8) accord- (Fig. 2). The northeastern Adriatic region (#17) encompasses the Gulf
ing to the geographical distribution of the data. Sea-level data from of Trieste (Italy and Slovenia) as well as the Istrian coast and the Island
Pianosa Island were included in region (#6) due to its proximity to of Pag (Croatia). Ongoing vertical movements are lower than