Page 3 - Cipriano_Madonia_alii_2017

82 DI MAGGIO, MADONIA, VATTANO, AGNESI and MONTELEONE

Oligocene–middle Miocene turbiditic deposits
(Numidian flysch) cover the Sicilide, Imerese, and
Panormide rock successions; lower–upper Miocene
deformed foreland marls cover the Sicanian, Trapa-
nese, and Saccense rock successions; Oligocene–
Quaternary foreland open shelf carbonates cover the
Iblean–Pelagian rock successions; 5) A thick pack
consisting of middle Miocene–Pleistocene foreland,
wedge-top and foredeep basin deposits (terrigenous,
evaporitic, and clastic carbonate rocks), which
largely form the Gela Thrust System; 6) A deep-
seated and buried foreland, slightly deformed, crops
out only in the south-eastern end of Sicily and in the
floor of the Sicily Channel.
Fig. 2 shows simplified stratigraphy and original
facies domains of the rock bodies of western Sicily.
The tectonic evolution of the western Sicily belt
was a progressive accretion of thrust sheets (Cata-
lano et al. 2000) and duplex formation (Catalano et
al. 1996), combined with the clockwise rotation of
the allochthonous blocks (Oldow et al. 1990;
Speranza et al. 2003).
In this context, a Miocene contractional deforma-
tion originally produced the progressive detachment
of the Sicilidi units and Numidian flysch cover
(Puglisi 2014) and their stacking over deep water
carbonates (Imerese units), in their turn overthrus-
ting both Sicanian units and shallow water carbo-
nates (Panormide, Trapanese, and Saccense units
— Catalano et al. 2013). Deposition of coeval fore-
deep and wedge-top sediments (Butler et al. 2015;
Gasparo Morticelli et al. 2015) accompanied the for-
mer event of shallow seated thrusting. Subsequently,
during the Pliocene Epoch a deep-seated transpres-
sive event redeformed the innermost tectonic units
stacked during the first Miocene event (Avellone et
al. 2010); more externally, a contractional event pro-
duced the inception of the wedging of the Gela
Thrust System overlying the earlier and shallower
allochthonous units. These two events also involved
the wedge-top basin marly carbonates of the Trubi
unit (lower Pliocene; Fig. 2), which are widespread
all over Sicily up to the higher altitudes (over 1400 m
a.s.l.; Abate et al. 1991). Finally, a Plio–Pleistocene
back-arc tectonics originates high-angle extensional
faults affecting the northern coastal area of Sicily
and southern Tyrrhenian Sea (Pepe et al. 2005;
Cuffaro et al. 2011).

Topography

The presence of a main fold-thrust belt influences
the relief of Sicily (Figs. 1, 3). An E–W mountain Fig. 2. Schematic stratigraphy and original facies domains of the rock bodies of
range (Sicilian Apennines) is its topographical western Sicily (data compiled from various Authors — e.g., Catalano et al. 2013
expression. The range forms a long and almost — modified and simplified).

GEOLOGICA CARPATHICA, 2017, 68, 1, 80 – 93