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Fig. 4. Location of the example site in Burmarrad, Malta. Molluscan and ostracod assemblages of the core BM1 indicate that the dated charcoal was deposited in semi-enclosed lagoon
facies. The sample, collected at −10.1 MSL yielded a radiocarbon age of 6500 ± 30 years (7326–7471 ka BP 2σ). After correction for the indicative range, we produced an index point
placing the RSL at −9.6 ± 0.55 (details in Section 3.3).

and Sanso (2002); Mastronuzzi and Sansò (2012) provided evidence for above ~−14.2 m MSL at ~5.2 BP in Northern Corsica and Pianosa (#6,
a co-seismic RSL change greater than 0.5 m at ~1624 AD. Similarly, on Sartoretto et al., 1996, Appendix C) is not useful because several other
Pag Island (Nortwestern Adriatic #17), detailed investigation indicated data-points demonstrate that RSL was already above ~−6 m MSL at
a co-seismic subsidence at ~1100 AD (Marriner et al., 2014). Therefore, this time (Fig. 7, #6). Finally, we excluded samples with poor or absent
at sites where co-seismic vertical movements were documented by pre- descriptions of the depositional environments.
vious studies, we did not use the RSL data-points older than the seismic Spatially, RSL reconstructions covered most of the north-
event, whose current position was significantly influenced by the rapid western Mediterranean coast whereas Tunisia represents the sole
vertical movement. Obviously, we cannot exclude that presently un- region located on the southern Mediterranean seaboard, where
known seismic events may have influenced the position of some data paucity did not allow a robust RSL reconstruction for Algeria
index points in tectonically active regions included in our database. and Morocco (Fig. 1). The age range of the data spans the last
We further excluded the RSL data-points showing a high degree 14 ka, with constant increase in the number of index and limiting
of compaction. For instance, an index point placing the RSL at points throughout the Holocene (Fig. 5B). Compaction-free index
~−11.1 m MSL at ~6.7 ka BP in the Rhone Delta (Southern France, #3, points (e.g., L. byssoides, beachrocks and archeological index
Vella et al., 2005, Appendix C) is inconsistent with a suite of points plac- points) and basal index points represent 28% and 14% of the data-
ing the RSL at least ~5 m higher at the same time. This evaluation was base, respectively. The majority (52%) of the index points included
only possible at sites where RSL reconstruction was based on multiple in the database is intercalated (Fig. 5B).
proxies. Reconstructions based on small datasets or only on intercalated
samples are thus less reliable and caution must be used when compar-
ing these data with the GIA models. 5.1. Central Spain (#1)
In addition, we rejected a large amount of data not useful for RSL re-
construction. For example, a marine limiting point constraining the RSL The RSL history of the Central Spanish coast is composed of 13 index
points and 13 limiting points (Fig. 6,#1) from coastalareas between Va-
lencia and Alicante. The oldest index point places the RSL at −16.0 ±
0.6 m at ~9.1 ka BP. RSL rose to −10.6 ± 0.6 m at ~8.6 ka BP and to
Table 2
Viscosity parameters used to predict the nominal, maximal and minimal RSL curve for −6.1 ± 0,7 m at ~8.3 ka BP. Two points document the progressive rise
each region. between ~8.3 and ~7.1 ka BP when an index point places the RSL at
−3.5 ± 0.5 m. Two marine limiting points (shallow shoreface) indicate
Viscosity parameters (Pa s)
ICE 5G VM2 RSL was slightly above −2 m at ~6.5 ka BP. Between ~6.0 and ~5.0 ka
Upper mantle Transition zone Lower mantle BP terrestrial samples constrain the RSL below the present datum. Late
Nominal 0.5 10 21 0.5 10 21 2.7 10 21 Holocene intercalated index points show scatter, most likely related to
Maximal 0.8 10 21 0.8 10 21 5.0 10 21 sediment compaction. Less compacted index points indicate that RSL
Minimal 0.2 10 21 0.2 10 21 1.0 10 21 was at −0.9 ± 0.6 m at ~3.4 ka BP and at −0.3 ± 0.5 m at 1.1 ka BP.