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