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154 Ślączka A. et al.

during Lower Pleistocene (ABATE et al., 1995) and by re- del Pozzo and Punta di Ferro, outcrop gravels and sand-

gional sea level fluctuations (TROPEANO & SABATO, 2000) stones of Pleistocene age are deformad by NW-SE and

have an important role for the Favignana area. W-E oriented strike-slip faults (INCANDELA, 1996; ABATE

et al., 1995; 1997). In the northern sector of the island

(Punta Faraglione), right-hand strike-slip faults oriented

2. GEOLOGICAL SETTING from NW-SE to W-E, formed a set of meters-in-scale

graben-like structures, filled by marine deposits of Pleis-

The Favignana Island belongs to the Egadi Archi- tocene age. This deposits are deformed by left-hand

pelago (Fig. 1) that represents an emerged part of the strike-slip faults NE-SW striking. Finally, the Pleistocene

Egadi Thrust Belt (ABATE et al., 1995-1997) of Sicilian- sandstones outcropping in the eastern sector of the isl-

Maghrebian system (SULLI, 2000; NIGRO & RENDA, and are folded to form a gentle anticline, interpreted as a

2001). Favignana is mainly build-up of Mesozoic-Lower drag-fold by INCANDELA (1996) and ABATE et al., (1995).

Tertiary carbonate deposits, unconforma-

bly capped by younger sediments which

are represented by biocalcarenites and

biorudites of Early-Middle Miocene and

marly shales of Late Miocene (CATALANO

et al., 1996; ABATE et al., 1997). Mesozoic-

Lower Tertiary carbonate deposits are un-

conformably covered by Middle-Upper Pli-

ocene bluish marls and shale followed by

Lower Pleistocene calcareous deposits

and by Tyrrhenian calcarenites and bioru-

dites. The Lower Pleistocene depo sits are

widespread along the eastern slope of the

emerged paleo-Favignana Island in a pull-

apart Basin, probably generated by trans-

tensional faults activity.

Three faults systems, recognised in

the Favignana Island, displace both the

Mesozoic-Tertiary and Pleistocene depo-

sits (Fig. 3). The first system, represented

by N-S strike-slip faults, bounds the ridge

of Favignana and somewhere it reac-

tives/displaces the Miocene thrusts (ABATE

et al., 1995). The other faults systems NE-

SW and NNW-SSE oriented at low-angle

pitches.

Minor positive flower structures 1-to-10

meters in scale have also been observed

(INCANDELA, 1995; 1996; ABATE et al.,

1995). In the eastern sector of the island,

joints and minor strike-slip faults deform

the deposits of Pleistocene age, as well as

the more younger breccias and paleosoils

with displacements ranging from 0.1 to 1

m. This faulting activity determined small-

scale block tilting, as recognised at Cala

Monaci. In the middle-southern sector of

the island a N-S oriented morphostructure

(so-called Promontorio Scindo Passo), is

located and bounded by two strike-slip

faults. The outcropping Pleistocene depo-

sits are displaced by minor right-hand

transtensional and normal faults oriented

NNW-SSE. This grid of minor faults deter-

mined pull-apart like geometries In the

north-western sector of the island (Punta

Sottile) outcrop conglomerates and sand-

stones of Pleistocene age, that are dis-

placed by strike-slip and normal faults Fig. 1. - a) Schematic structural map of the Western Sicily; b) Schematic geological map
oriented from NW-SE to W-E. The sand- of the Favignana; c) Pleistocene facies distribution in the eastern Favignana Island.
stones also fill the faults-related joints,
suggesting soft-sediment deformation pro- a) Carta strutturale schematica della Sicilia Occidentale; b) Carta geologica schema-
cesses. Also, between the localities of Cala tica dell’Isola di Favignana; c) Distribuzione delle facies pleistoceniche nel settore
orientale dell'Isola di Favignana.