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Facies (2007) 53:389–400
The studied sequence ends with a decimetre-thick bed of
intraformational breccia (MF8), representing a transgres-
sive surface.
Conclusively, the depositional setting of the Punta Bas-
sano succession was a carbonate ramp with very low topo-
graphic relief and hence created extremely large
homogeneous facies tracts. As shown above, the accommo-
dation space created suYcient palaeobathymetry to gener-
ate more open higher hydrodynamic conditions by both
wave and tidal action. The increase of accommodation
space was probably initiated by subsidence, followed by
platform Xooding and hence transgression. Inversely, sea-
level falls could quickly isolate the ramp interiors reducing
the hydrodynamic energy levels, and creating widespread
lagoonal-peritidal restricted environments and fresh water
circulation.
Conclusions
The Upper Triassic Punta Bassano succession at Marettimo
Island (Egadi Archipelago, Sicily) provides valuable sedi-
mentological and palaeontological data for the interpreta-
tion of the depositional environment and to precise the
palaeogeographic scenario.
• Biostratigraphy, based on foraminiferal and palynologi-
cal data, indicates a Carnian-Norian to Rhaetian age for
the Punta Bassano section. This range is consistent with
the indications given by ostracod associations.
• The whole succession has been deposited in a shallow
inner ramp zone, including open-marine as well as
lagoonal and peritidal protected environments. Low- and
high-energy shoal facies have been recognised and their
lateral distribution along the carbonate ramp has been
reconstructed. Periodic storm activity inXuenced the dis-
tribution and preservation of textural components. Depo-
sitional systems analysis revealed the existence of Wve
cycles, displaying shallowing-upward trend.
• Facies types and biostratigraphic content are closely
comparable to those known from the Upper Triassic
epeiric carbonate platform on the northwest to northeast
margin of the Tethys Ocean (e.g. Lofer sequences and
Kössen Formation in the Northern Calcareous Alps; Fat-
ric Unit in the West Carpathians; Calcare di Zu Forma-
tion in the southern Calcareous Alps). However, the
Punta Bassano facies indicate a more restricted position
of the intra-platform environments because (1) patch-
reefs and derived skeletal grains are missing, and (2) by
the poor diversity of the microfaunal assemblages.
• The comparison of facies and microfauna with those
from other Mediterranean coeval sequences (Pyrenees:
Fréchengues et al. 1990, 1993; Peybernes et al. 1988;
399
Corsica: Peybernes et al. 1991; Sardinia: Carillat et al.
1999; and Tunisia: Kamoun et al. 1994) allow us to con-
Wne the Punta Bassano’s sedimentation on the northern
margin of the Tethys Ocean, of the European crust
between Corsica and Pyrenees. Before this study, Maret-
timo Island was considered as located in the internal part
of the Panormide carbonate platform, during the Late
Triassic (Abate et al. 1978a, 1978b, 1982).
• These new results reWne the existing regional tectonic
model and indicate that Marettimo Island, which is con-
sidered as a single structural element, is a piece of the
southern margin of the European Plate displaced further
to the detachment of the Corso-Sarde block and incorpo-
rated within the Egadi Archipelago.
Acknowledgments The authors wish to thank the reviewers (Prof.
A. Munnecke and an anonymous reviewer) for their very constructive
remarks, and express their sincere gratitude to Dr. S. Crasquin-Soleau
(CNRS-Université Pierre et Marie Curie, Paris, France) for help with
the determination of the ostracods. We are grateful to J. Metzger (Uni-
versity of Geneva) for the help in computer drafting. This work was
Wnancially supported by the Swiss National Science Foundation.
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