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Panormid carbonatic platform and its margins on
units belonging to other palae-ogeographic
domains (such as the Trapanese basin; Giunta and
Liguori, 1972; Abate et al., 1991, 1993; Catalano
and D’Argenio, 1982); the piling up of SE-
verging thrust sheets in the Middle –Upper
Miocene and in the Middle Pliocene tectonic
phases determined the overlying of brittle rocks
over more ductile rocks.
Further (Pleistocenic) disjunctive and strike-slip
tectonics, occurred mainly along NW–SE, NE–
SO, N–S and E–W oriented normal fault systems,
caused the splintering up into blocks with
differential raising and the formation of structural Field relationships between rocks of the
highs alternated to basins (D’Angelo et al., 1997).
In the Capo San Vito Promontory, this is
reflected by the occurrence of lowered sectors,
presently occupied by coastal plains (Castelluzzo
and Cornino Plains; Abate et al., 1991).
Moreover, the recent tectonics created favorable
conditions for the onset of both deep-seated and
surficial gravitational slope deformations, which
are particularly widespread along the eastern
flank of the peninsula (Agnesi et al., 1995). The
Capo San Vito Promontory and the Island of
Marettimo are characterized by Mesozoic–
Tertiary units composed of carbonatic, evaporitic
and silicoclastic deposits, overlain in discordance
by late orogenic clastic deposits (Abate et al.,
1991, 1996). Several orders of subhorizontal
abrasion surfaces, interpreted as raised marine
terraces, are present at different heights (up to
160 m) along wide coastal tracts of the W Sicily.
Their formation has been considered to be of
Middle-Upper Pleistocenic age, since they cut not
only carbonatic rocks and marl-stones of
Mesozoic age but also terrigenous, evaporitic and
calcarenitic formations of Late Miocene to Lower
Pleistocenic age (D’Angelo and Vernuccio,
1996).
2.2. NE Area
Northeastern Sicily is situated at the southern
margin of the Tyrrhenian microplate, which
includes Calabria (Gvirtzman and Nur 1999). The
area of NE Sicily is composed of sedimentary and
metamorphic rocks within a southward-verging
system of thrusted nappes, the Appennine-
Maghrebian Chain, developed above the
northward-dipping African plate. The resulting
tectonic depression above the margin of the
African plate has created a foredeep along the
northern margin of the African continental crust
which is occupied by early Quaternary clays.
2
These clays form the substrate for much of the
eastern and southern flanks of the Mount Etna
volcanic edifice and are known as the sub-Etnean
clays (Lentini, 1982). Farther to the south, this
African crust is represented at the surface by the
platform carbonates and clastics of the Hyblean
plateau which make up southeastern Sicily. To
the north of Sicily, in the Tyrrhenian Sea,
subduction is marked by the Aeolian Islands
volcanic arc. Overall, this tectonic regime
imposes north-south compression to the
northeastern Sicily region (Lanzafame et al.,
1997).
Appenine-Maghrebian Chain and the early
Quaternary marine clays indicate that thrusting in
this compressional regime continued until at least
mid-Pleistocene times (Lanzafame et al., 1997),
while active regional uplift is indicated by several
lines of evidence. In particular, the early
Quaternary marine clays are now found several
hundred metres above sea level (Romano, 1979),
and well developed uplifted Tyrrhenian marine
erosional platforms occur at about 130 m at
Taormina as well as in Calabria on the other side
of the Messina Straits.
This compressional framework is transected by a
number of seismogenic structures of regional
tectonic importance. Of these, the largest is the
Malta Escarpment, a structure that intersects the
African margin on the southern side of the
Mediterranean at a high angle. It strikes NNW-
SSE and defines the eastern and southeastern
edge of the Sicilian continental shelf, marking the
boundary with the oceanic-affinity crust of the
Ionian Sea to the east. Dip-slip displacement on
the Malta Escarpment amounts to some 3 km, and
where it intersects the coast of Sicily on the
eastern side of Mount Etna a series of active
faults (the Timpe fault system) produce scarps up
to 200 m and fault planes displaying both dip-slip
and right oblique slip kinematic indicators
(Lanzafame et al., 1996; Monaco et al., 1997).
This major structure, although its continuity is
disrupted by interactions with other faults, has
been interpreted as passing through northeastern
Sicily as a series of structures which ultimately
displace the Aeolian arc by approximately 6 km
in a right-lateral sense (Lanzafame and Bousquet,
1997).
The most important structure which intersects the
faulting associated with the Malta Escarpment is
the NNE-SSW striking Messina fault system. The
1908 Messina earthquake was attributed to a