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material and the development of megarippled dunes has
been observed locally, due to high energy landwards
waves. During tsunami-related high-energy events scat-
tered large erosional structures were probably formed.
Similar events triggered local debris flows. Storm-gene-
rated sedimentation units are underlined by the erosion
surfaces on which some channels, up to tens meter wide
and several meters deep took place. Besides storm
wind-induced currents were active producing longshore
and rip currents that deposited seaward dipping cross-
bedded calcarenites which spread out on distance of
hundreds of meters. The storm periods were separated
by fair weather intervals: cross-ripple beds were colo-
nized by population of burrowing organisms thus pro-
ducing pervasive bioturbation. The bioturbated deposits
were frequently eroded by series of storms. During in-
tense storm the erosion cut deeper part of dunes and
episodic, low angle dipping surfaces;. the development
of such erosional surfaces was also controlled by uplift-
ing of the substratum and by relative change of the sea
level. Synsedimentary strike-slip tectonics were besides
reported for Favignana area. The relevant thickness of
the Facies Association E, more than 40 meters, also
suggests a generalized fault-induced downward move-
ments of the substratum7. Typical vertical and lateral
sequences of sedimentary structures in storm deposits
were represented by subhorizontal lamination suc-
ceeded by about-planar cross-bedding, hummocky type
cross stratification or/and rarely wave ripple lamination.
The top of sequence is often bioturbated, as an effect of
recolonization by fauna during fair weather.
The recognized Facies Associations also differ in
ichnofacies content: in FA A ichnofossils are rare and
mainly represented by short vertical tubes; in FA B wide
areas are colonized by Thalassinoides and, more rarely,
by vertical burrows (Cruziana and Skolithos ichnofacies);
in FA C traces produced by Echinoidea; in FA D Skolithos
ichnofacies and horizons pervasively bioturbated are
common, locally cluster of insects burrows have been ob-
erved; in FA E trace fossils are rare and are limited to few
traces of Echinoidea and some vertical burrows, while
pervasive bioturbated horizons are common.
The recognized Facies Associations also differ in
ichnofacies content: in FA A ichnofossils are rare and
mainly represented by short vertical tubes; in FA B wide
areas are colonized by Thalassinoides and, more rarely,
by vertical burrows (Cruziana and Skolithos ichnofacies);
in FA C traces produced by Echinoidea; in FA D Skolithos
ichnofacies and horizons pervasively bioturbated are
common, locally cluster of insects burrows have been ob-
erved; in FA E trace fossils are rare and are limited to few
traces of Echinoidea and some vertical burrows, while
pervasive bioturbated horizons are common.
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