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8 M. GASPARO MORTICELLI ET AL.

Downloaded by [Universita di Palermo] at 02:49 07 January 2016 Figure 6. (a) ENE-WSW syn-depositional normal fault; locally divergent stratal pattern is recognized in marly layers (b); Marettimo
Formation, Cemetery locality. (c) ENE–WSW normal faults separating the Monte Falcone Formation (MFA; Lias) from the Argilliti di
Punta Troia (APT; Malm – lower Cretaceous) along a buttress unconformity surface sensu Davis and Reynolds (1996) cropping-out at
Punta Troia promontory (d).

6.2 Compressional event transpressional and the compressive inherited struc-
tures is also well documented. The most striking effect
In the Pizzo Spirone area (Main Map), the Falcone unit of this interference is the exhumation and re-defor-
thrusts over the Bassano Unit along a WNW- to NW- mation of the pre-existing tectonic structures. The
dipping fault plane; here, thrust faults are associated hinge of the syncline structure (Figure 8(a) and 8(b))
with fine-grained cataclasites (Figure 7(a)). Towards the observed in the southern sector of the island (between
thrust forelimb, duplex structures and minor anticlines the Posaturo and Conca area, Main Map) displays a
show a southeastward transport direction (Figure 7(b)). clockwise rotation, while the axial plane is not much
inclined and locally southward-dipping. On the Cala
Along the Punta Bassano promontory, minor asym- Marino side, a NNW–SSE dextral high-angle transpres-
metric folds with an ENE–WSW axis (Figure 8(b)) in sive fault uplifted and re-deformed the syncline struc-
the Bassano Unit are associated with the reverse flank ture (see geological cross section in the Main Map).
of a SE-verging syncline (Figure 8(a)). Similar NE–
SW asymmetric folds are also well exposed in the Posa- 7. Discussion and conclusions
turo. Symmetric folds compatible with a major syncline
hinge zone are locally documented (Figure 8(c)). The 7.1 Tectono-sedimentary evolution during the
structural analysis evidences a major syncline, with Mesozoic interval
NE-SW axis, compatible with the SE-verging thrust.
The hinge zone of the syncline is partially cropping- Stratal pattern and facies analysis contributed to locat-
out along the apparent monocline of Punta Bassano ing the Mesozoic Marettimo succession in a portion
promontory (Main Map). (which we propose to call the Marettimo domain) of
the southern margin of the Tethyan ocean, character-
6.3. Transpressional event ized since the Triassic by a wide carbonate platform
environment.
NNW–SSE trending, right-lateral high-angle faults and
cylindrical folds characterized by high-angle plunging The middle-upper Triassic Marettimo formation
document this tectonic event. The high-angle faults, deposited in a peritidal sector of a carbonate platform,
with 0–30° slickenline rake, are compatible with a N– which was controlled by SSE-ward dipping syn-
S σ1 orientation. The interference among the sedimentary normal faults (Figure 6). A very shallow-