Page 1 - Massoli-Novelli_2005

Il Quaternario
Italian Journal of Quaternary Sciences
18(1), 2005 - Volume Speciale, 137-143

THE MAIN GEOMORPHOSITES OF THE EGADI ISLANDS
(SICILY, ITALY)

Raniero Massoli-Novelli
Via della Mendola, 85
00135 Roma, Email: massoli@tiscali.it

ABSTRACT: R. Massoli-Novelli, The main geomorphosites of the Egadi Islands (Sicily, Italy). (IT ISSN 0394-3356, 2005).
This article describes the main geological and geomorphological features of the three main Egadi Islands: Favignana, Levanzo and
Marettimo. These islands, which are essentially made up of Mesozoic carbonate rocks, are considered as the continuation in the sea
of the north-western Sicilian chain.
In addition, the main geomorphosites of these three islands are identified for the first time: these are the numerous, significant coastal
caves. Particular emphasis is given to natural and anthropogenetic geomorphosites related to the Pleistocene bioclastic calcarenite
caves present in Favignana, an ancient site of intense quarrying activities.

RIASSUNTO: R. Massoli-Novelli, I principali geomorfositi delle Isole Egadi (Sicilia, Italia). (IT ISSN 0394-3356, 2005).
Vengono evidenziate le principali caratteristiche geologiche e geomorfologiche delle tre maggiori isole delle Egadi, Favignana, Levanzo
e Marettimo, costituite essenzialmente da rocce carbonatiche mesozoiche e considerate la prosecuzione in mare verso ovest della
catena nordoccidentale della Sicilia.
Vengono poi individuati per la prima volta i principali geomorfositi delle tre isole, in gran parte costituiti dalle numerose e rilevanti grotte
costiere. Particolare risalto viene anche dato ai geomorfositi, naturali ed antropici, relativi alle cave di calcareniti bioclastiche pleistoce-
niche esistenti a Favignana, luogo di antica ed intensa attività estrattiva.
Keywords: Geomorphosites, Calcarenite, Egadi Islands, Italy.
Parole chiave: Geomorfositi, Calcarenite, Egadi, Italia.

1. INTRODUCTION AND GENERAL GEOLOGICAL The presence of compact calcareous-dolomitic
SETTING rocks explains the two essential geomorphological cha-
racteristics of the Egadi Islands: cliffs and high reliefs in
The Egadi archipelago is formed by three main all the islands, especially in the two smaller ones, and
islands – Favignana, Levanzo and Marettimo – and the many large caves. The highest peak is Mt. Falcone in
islets of Maraone and Formica. Marettimo, which reaches a height of 686 m. Not only is
All these islands are geologically linked to the this island the furthest from the Sicilian coast but it is
adjacent mainland. In other words, the Egadi are the also the one most affected by tectonic processes, with
continuation in the sea of the backbone chain of north- numerous overthrusts and transcurrent faults (Abate et
western Sicily (Fig. 1). al., 1995, 1996).
The basic geological composition of this archipe-
lago corresponds to calcareous-dolomitic rocks, ran- Favignana is the largest of the Egadi Islands.
ging in age from the Triassic to the Miocene. Owing to its shape, it is compared to a butterfly: at the
Subsequently, layers of sandstones were deposi- centre of the island, a north-south ridge of Mesozoic
ted on top of the carbonate rocks. In particular, biocla- calcareous-dolomitic rocks stands out, reminiscent of a
stic calcarenites crop out abundantly on the largest butterfly’s body. At the sides, calcareous marine sedi-
island of Favignana. They are typical poorly cemented, ments to the west and arenaceous marine sediments to
easily workable, yellowish calcareous limestones rich in the east were subsequently deposited on these hard
pelecypods, especially the Pecten genus. Owing to and compact carbonate rocks, forming two small
these characteristics, since the 1700s this stone has plains: the butterfly’s wings.
been called “tufo” (i.e., tuff; a similar wrong definition In the plain to the east, abundant strata of
has been given to the stones of Matera in Basilicata). Pleistocene bioclastic calcarenites crop out (the “tufo”
These limestones have been intensely quarried through or Favignana stone previously mentioned). These rocks,
time. No detailed studies have been ever carried out on between a few centimetres to about 30 cm thick, show
this interesting stone, although it appears to be quite a generally sub-horizontal bedding. The calcarenite is a
similar to the proximal bioclastic calcarenite outcrops of marine, very rich in fossils (pelecypods, corals, remains
the Lower Pleistocene along the coast of Marsala of fish, etc.) calcareous sandstone.
(Ruggieri et al., 1975) and in San Vito Lo Capo The isle of Levanzo, which is the smallest of the
(Antonioli et al., 1994). three main Egadi Islands, is famous for its rugged land-