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166 Ślączka A. et al.
Fig. 16 - Higher part of the Lower Pleistocene sequence started horizontal laminated calcarenites. In more western
with large cross-bedded calcarenites that dipping to NW (land- (landward) part (Torretta area), visible fragment of Fa-
ward) covered by calcarenite with low angle seaward dipping cies Association sequence two, almost flat, erosional
lamination and by set of cross-bedded calcarenites with at least surfaces divide into three parts (Fig. 12a) each calcare-
two orders of bounding surfaces. Upper surface of this set is nitic body. Each part shows complex internal structures;
erosional and covered by thick sand body with subhorizontal particularly the middle one consist in subhorizontal stack
lamination that terminated by ripple laminated calcarenites (R). and in cross-bedded sandbodies (Fig. 12b). This organ-
Note that bioturbation in cross-bedded calcarenite, on the right ization is preserved on distance of tens of meters, with
side of the picture, marked by letter B, disappears to the left, in local landwards opposite direction of cross-bedding. At
more elevated part. Facies Association E, upper part of a bar Calarossa and Bue Marino localities, the outer part of
system. Cala Fossofelle, Case Di Vita. calcarenite body is characterized by cross-bedding dip-
ping both landwards (Fig. 13b, c), as well seaward (Figs
Parte più elevata della sequenza del Pleistocene inferiore che 13b-f, 14 and 16). Somewhere, single or sets of me-
inizia con calcareniti, a stratificazione incrociata a grande scala dium-sized conical or diapiric structures can be ob-
immergenti verso NO (verso terra), ricoperte da calcareniti la- served at the top of horizontal laminated body (Fig.
minate debolmente immergenti verso mare e da un gruppo di 13e). Cross- and horizontal-bedded calcarenites are cut
strati di calcareniti a stratificazione incrociata. La superficie su- by several channels, generally filled up by cross-
periore di questo gruppo di strati è erosiva ed è ricoperta da laminated bodies (Fig. 13e); locally, stacks of channels
uno spesso corpo sabbioso con laminazione suborizzontale che are visible (Fig. 15). A small synsedimentary slump was
termina con calcareniti laminate con strutture da ripple (R). Si formed along the wall of channel (Fig. 15). In topmost
noti che la bioturbazione nelle calcareniti a stratificazione incro- part of the sequence there broad channels filled by
ciata, sul lato destro della figura marcato dalla lettera B, scom- cross stratified bodies have benn observed (left part of
pare verso sinistra nella parte più elevata. Associazione di Fa- Fig. 13f and Fig. 16), locally the filling shows lags of
cies E, parte superiore di un sistema di barra. Cala Fossofelle, pebbles and rhodolithes or of debrites at the bottom,
Case Di Vita. graded in their lower portion and containing scattered
rhodolithes and shell fragments. Along the western
40 meters in Cavallo-Torretta area. This Facies in Cala- boundary of Cavallo locality exceptionally large and deep
rossa and Cala Canalleddi area rest directly on the up- channels were developed: one of them, more than 10
lifted Lower Pliocene marls (ABATE et al., 1995-1997) or meters deep, is infilled by homogenous calcarenites
sediments similar to Facies Association C5. The main (fluxoturbidite type; ŚLACZKA & THOMPSON, 1981);
part of this Facies is built of thick- and very thick-bedded another one, tens of meters broad and more than 15
sequences of, coarse-grained calcarenites, with subho- meters deep, is visible along the northern cliff of the
rizontal and/or low angled lamination, and of calcare- same locality (Fig 12a). Intercalation of layers of perva-
nites with large-scale cross-bedding (Figs 12, 13b,f). sively bioturbated calcarenites (from dozen centimeters
Calcarenites with hummocky cross-lamination (Fig. 13b, to one meter thick) occurs locally (Fig. 13a, b, and f). A
uppermost part) also occur. Seaward- and landward-di- typical feature of some cross-bedded bodies consists in
rected, as well as shore-parallel, sets of cross bedding laminated-to-bioturbated pattern, similar to those de-
are observed (Fig. 13 b, d, and e)6. scribed by D’ALESSANDRO & MASSARI, (1997): normal
and bioturbated laminae are alternate (Fig. 13c). In
The majority of calcarenite beds presents lower some cases, only a lower part of inclined laminae shows
and upper sharp, erosional surfaces. However, locally bioturbations (Figs. 13e and 16). Sporadically, traces of
higher horizontal laminated bedform rest on non-eroded Echinoidea occur in the lower part of the sequence.
rippled upper surface of the lower bed. Calcarenite beds Scolithos-type of burrows is extremely rare and occurs
form bodies long some of tens of meters, each gradually in higher part of the sequence. Bioturbation disappear in
wedging out; lateral changes of facies have been ob- the highest part of the sequence (Torretta).
served. Locally, asymmetric, cross-bedded mega-ripples
(few tens centimeters high and several meters long) are Coarse-grained and conglomeratic sandbodies,
preserved (Fig. 14). Also, symmetrical sandwaves (up to occurring in the lowest part of Facies Association, more
50 cm high and several meters of length), built-up of than two kilometers from the ancient shoreline, probably
homogenous sand have been observed on the top of represent storm-reworked beds, redeposited from the
shoreline and distributed on the shallow shelf, east from
paleo-Favignana Island, by high energy currents. The
main part of Facies Association E consists of mixed fa-
cies of thick and very thick bedded, planar or cross-
laminated, sandbodies, showing often characteristic fa-
cies succession from planar and/or crossbedded to
hummocky-like and/or medium trough cross-lamination,
bounded by unconformity with local channels represents
the outer part of shoreface zone, marked by offshore
bars/ridges system related to storm high-energy epi-
5 In Punta Marsala where Facies Association E is underlayed by Facies Association C the profile starts with trough cross-bedded fine-
grained calcarenite, horizontally laminated, fine-grained muddy calcarenites (Fig 13a), with traces of Echinoidea, covered by layer (up
to 50 cm thick) built-up of shell fragments covered by several meters calcarenite, generally pervasive bioturbated.
6 Locally, in elongated lens-like bodies, laminae are sinusoidal, and cross-bedded sandbodies form tabular cossets. The ripple cross-
laminated bodies (up to 1.5 m thick) locally rest on tabular cross-stratified or horizontal laminated sandbodies.
