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10 M. GASPARO MORTICELLI ET AL.
Downloaded by [Universita di Palermo] at 02:49 07 January 2016 to extensional tectonics, as supported by the slightly
divergent stratal pattern.
The development of the tectonic subsidence, and the
related dismembering of the carbonate platform mar-
gins continued up to the Malm-Early Cretaceous, as
shown by the unconformity surface separating the
Marettimo Formation from the Monte Falcone For-
mation (Figure 3) and the other stratigraphic features
of the Falcone succession.
Normal faulting proceeded in the early Liassic (Fal-
cone succession), leading to the thinning of the Jurassic ternary coastal deposits were in turn accumulated
platform and settling of the slope environment, with
accumulation of a thick wedge of resedimented depos-
its (Figure 2(c)). We consider the upper portion of the
Falcone succession to be a slope-to-basin sequence (see
stratigraphic columns in the Geological map). Liassic
platform-derived clasts in the resedimented wedge of
Punta Troia (MFA1–2), settled in a slope (periplatform
talus or base-of-slope apron, Bosellini, 1991) close to a exposed in the Punta Troia area (Figure 5(a)–(c)).
fault-bounded carbonate platform edge (Mullins &
Neumann, 1979). The Dolomites and dolomitic marl
alternations (MFA3) of the Falcone Formation accu-
mulated in more distal areas.
During the late Liassic-Dogger, progressive deepen-
ing due to the extensional faults (Figure 6(c)) accounted current level (Ferranti et al., 2006). Possible deviations
for widespread pelagic sedimentation, and cherty lime-
stones (PZS) covering the slope deposits (MFA) or rests
directly on the shallow-water limestone (MAR). During
the Liassic-Dogger interval, the inner sectors of slope
were undernourished and Fe–Mn oxy-hydroxide
encrusted surfaces formed. These surfaces, considered
an inherited rock ground (sensu Clari, Dela Pierre, &
Martire, 1995), directly cover the inner slope conglom-
erates (MFA1), according to the Bahamian-type carbon-
ate-slope bypass (Schlager & Ginsburg, 1981).
During the Malm-Early Cretaceous, a hemipelagic
environment was established, and respective deposits
(Argilliti di Punta Troia, APT) covered, along a but-
tress unconformity (sensu Davis and Reynolds, 1996;
Figure 6(c) and 6(d)), cherty limestones (PZS For-
mation), the encrusted surfaces and the conglomerates
and breccias of the MFA Formation. The calcareous
turbidites interbedded in the APT deposits around
Punta Troia (Figure 2(a)) indicate this sector close to
be an active slope. The local buttress unconformity
among the APT and their substrate demonstrates
that the extensional tectonics were active up to the
APT deposition.
7.2 Neogene to quaternary tectonic evolution
During the Miocene compressional event, the Maret-
timo domain was involved in the Sicilian-Maghrebian
mountain building. Two main tectonic units (Bassano
and Falcone Units) were stacked along a SE-verging
thrust. The syncline along the Punta Bassano promon-
tory is related to this deformation. The compressional
structures reactivated often previous (Mesozoic) exten-
sional faults. A subsequent transpressive tectonic event,
characterized by NNW–SSE right-transpressive faults,
displaced the older tectonic geometries and structures
driving the Island to the present tectonic setting.
Sea-level changes that occurred in the middle-late
Pleistocene, due to global climate change, have produced
repeated oscillations of the shoreline position at intervals
of about 100 and 20 ky. These shifts of the shoreline
determined the periodic emergence and subsequent
flooding of areas of continental shelf over which late Qua-
(during the rise of sea level) and dismantled (in whole
or in part), during the lowering of sea level.
These oscillations of sea level and the related to
shifting of the shoreline are the origin of vertical and
lateral stacking of alternating marine and continental
deposits around Marettimo Island (Figure 5) and well
Because global sea-level curves reconstructed for the
middle-late Pleistocene (Shackleton, 2000) suggest that
sea level reached up to the Mediterranean platforms
during highstand stages before the present day and
were almost equal to or a few meters higher than the
of position of the last highstand littoral deposits from
altitudes close to the present day sea level should be
attributed to tectonic processes of uplift or subsidence.
In the Egadi Islands on the whole, including Maret-
timo Island, coastal deposits of Tyrrhenian age out
crop at about 5–10 m above sea level (see also Abate
Buccheri, Renda, & Incandela, 1996; Antonioli
Renda, Silenzi, Verrubbi, & Parello, 1998), supporting
the absence of tectonic vertical movement during the
last 100 ky. Therefore, the uplift recorded by the conti-
nental shelf of Marettimo show that Plio-Pleistocene
tectonics have stopped, or have significantly deceler-
ated, since the Tyrrhenian (5e O2 isotopic stage).
Software
The geological map was compiled using Esri ArcGIS
and Global Mapper, with additional refinement using
Adobe Illustrator. Daisy 2.0 was used to produce the
stereonet plots (Salvini, 2001).
Acknowledgments
We wish to thank J. Abraham, S. Corrado and M.R. Barchi
for useful review of the manuscript.
Disclosure statement
No potential conflict of interest was reported by the authors.