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194 A. Slootman et al. / Earth and Planetary Science Letters 444 (2016) 192–204

Fig. 2. Sea cliff section displaying clinoform architecture and close-ups. For location see Fig. 1. (A) Photo panel and line drawing showing first order boundaries between
clinoform units. Note 2.5× vertical exaggeration. (B) Photo panel and line drawing of the proximal section of the examined backset-bedded clinoform unit. Note erosional
character of the base. (C) Photo panel and line drawing of dune cross-bedded clinoform unit. Encircled numbers indicate hierarchy of bounding surfaces: (1) clinoform unit
boundary; (2) set boundary; (3) compound cross-bed boundary; (4) cross-bed boundary.

2. Geological setting                                                  clasts. Quarries scattered across the island and a large sea cliff
                                                                       of seismic-scale dimensions (1.2 km by 50 m) offer textbook ex-
    Favignana (18 km2) is the principal island of the Aegadian         posures (Fig. 2). The studied deposits have been previously inter-
Archipelago, offshore western Sicily (Fig. 1A). The region belongs to  preted as the sedimentary record of an ancient shoreface cross-cut
the Alpine collision belt along the African–European plate bound-      by channels (S´ la˛czka et al., 2011).
ary, characterised by the superposition of thrust sheets since
Miocene times, on the front of which the Favignana wedge-top               The calcarenites and calcirudites of Favignana pass from tabular,
basin developed (Catalano et al., 2002). The (palaeo-)island’s main    low-angle shoreface packages onlapping the ridge, into a succes-
topographic feature is a ridge of tectonically emplaced Triassic to    sion of SE prograding ramp slope clinoform units up to 50 m
Miocene sedimentary rocks (Tavarnelli et al., 2003). At either side,   high, 500 m long and tens of m thick, dipping about 5–20 degrees
Pleistocene calcarenites and calcirudites, overlying Pliocene marl-    (Fig. 2). Clinoform units progressively thicken from their most
stones, are largely unaffected by tectonic deformation. The age of     proximal location in the vicinity of the ridge towards the large sea
the uppermost interval of the exposed marlstones is bracketed be-      cliff along the NE coast of the island in which clinoform units reach
tween the Last Occurrence (LO) of the foraminifera marker species      their maximum thickness and inclination. Ca. 50% of the clino-
G. sphaeroidinellopsis seminulina (3.19 Ma) and the LO of G. bonon-    form succession is composed of bioturbated (Thalassinoides), high-
iensis (2.41 Ma). These marlstones, therefore, belong to the Monte     angle cross-stratified calcarenites and calcirudites formed by the
Narbone Formation of southern Sicily (Catalano et al., 1998). The      S/SE migration of subaqueous dunes (Fig. 1). Such dunes migrated
Pleistocene calcarenites and calcirudites, which are the topic of      down the ramp slope under the influence of currents undergoing a
the present study, have hitherto not been dated. They comprise         slight deflection to the right (cf. Massari and D’Alessandro, 2012),
coarse-grained Heterozoan skeletal pack- and grainstones (1–2%         most likely imposed by the Coriolis force (e.g. Puga-Bernabéu et
non-carbonate particles), with locally abundant gravel-size bio-       al., 2010). The prograding, high-angle cross-bedded bodies, formed
                                                                       by downslope-migrating subaqueous dunes, are here referred to as
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