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4 M. GASPARO MORTICELLI ET AL.
Figure 3. Unconformity surface among the Monte Falcone Formation (MFA3) and Marettimo Formation (MARd). Punta Bombarda,
western coast of the island.
Downloaded by [Universita di Palermo] at 02:49 07 January 2016 4.1.2 Stratigraphy of the Bassano succession (1) Porto-Cimitero stratigraphic section: highlights
From the bottom, it is formed by: the sedimentary features of the middle-upper
part of the Marettimo Formation and its gradual
. Marettimo Formation (MARa): it shows the character- transition to the marly interval;
istics previously described, but yellow to brownish,
thin-bedded marls and marly limestone are upward (2) Conca stratigraphic section: this allows under-
interbedded to the shallow-water limestone and dolo- standing of the depositional environment and
mites (Figure 2(d) and 2(e)). Their thickness notably interaction between tectonics and eustasy;
increases along the Punta Bassano promontory (Main
Map). Here, 140 m-thick marls, marly limestone, shelly (3) Punta Libeccio stratigraphic section: this was ana-
limestone and dolomitic limestone are exposed. Intra- lysed for the relationships between the lithostrati-
formational breccias, with scour base, are frequently graphic units composing the Bassano succession and
interbedded with the marly deposits (MARc). The
elements are represented by centimetric, angular, shal- (4) Punta Troìa stratigraphic section: this displays the
low-water limestone, with enterolithic structures, sur- link between extensional tectonics and environ-
rounded by light brownish silt matrix (Figure 4). The mental changes.
top of the Marettimo Formation is represented by a
dark grey-laminated limestone and dolomitic limestone The first three sections pertain to the Bassano Suc-
with fenestrae and tepee-like structures (MARc). cession, the fourth to the Falcone Succession.
Basaltic rocks were observed in the middle portion 4.1.3.1 The Porto-Cimitero stratigraphic section.
of MAR, along the Punta Bassano promontory and Along the coast from Marettimo village to Punta Bas-
around the La Conca area. sano (Main Map), 130-m-thick shallow-water carbon-
ates exhibit lithological variation upwards that indicate
This formation widely crops out along the eastern two main facies associations:
coast of the Island, along the Punta Bassano promon-
tory and in the Punta Libeccio area. (a) blackish bituminous stromatolites, dolomitic
limestone and dolomites, algal laminites up to
. Monte Falcone Formation: massive beds of fine- 1 m-bedded; they show fenestral porosity and
grained dolomite and dolomitic limestone outcrop- desiccation structures as loferitic breccias and
ping at Punta Bassano (MFA3). tepee-like structures (Figure 2(e), 2(g) and 2
(h)). At places, calcarenites and laminated lime-
. Scaturro Formation (PZS): shows the characteristics stone are intebedded. The outcropping thickness
previously described. It crops out in the Punta Libeccio. is 60 m;
4.1.3 Stratigraphic sections (b) stromatolites, dolomitic limestone and dolo-
In order to better constrain the stratigraphic and struc- mites, algal laminites, interbedded with yellowish
tural setting, we analysed four representative strati- marls and yellow-blackish bituminous marly
graphic sections: calcilutites; the thickness and frequency of
marly intercalations increase upwards, and are
predominant at the top. The thickness is up to
70 m.
